E21.04 - Space Simulation Test Methods

SIGNIFICANCE AND USE
3.1 These practices enable the following information to be available:  
3.1.1 Material atomic oxygen erosion characteristics.  
3.1.2 An atomic oxygen erosion comparison of four well-characterized polymers.  
3.2 The resulting data are useful to:  
3.2.1 Compare the atomic oxygen durability of spacecraft materials exposed to the low Earth orbital environment.  
3.2.2 Compare the atomic oxygen erosion behavior between various ground laboratory facilities.  
3.2.3 Compare the atomic oxygen erosion behavior between ground laboratory facilities and in-space exposure.  
3.2.4 Screen materials being considered for low Earth orbital spacecraft application. However, caution should be exercised in attempting to predict in-space behavior based on ground laboratory testing because of differences in exposure environment and synergistic effects.
SCOPE
1.1 The intent of these practices is to define atomic oxygen exposure procedures that are intended to minimize variability in results within any specific atomic oxygen exposure facility as well as contribute to the understanding of the differences in the response of materials when tested in different facilities.  
1.2 These practices are not intended to specify any particular type of atomic oxygen exposure facility but simply specify procedures that can be applied to a wide variety of facilities.  
1.3 The values stated in SI units are to be regarded as the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements in space-simulation facilities. Acceptable vacuum-measuring equipment shall consist of those items in which performance is compatible with obtaining meaningful measurements. The gage mounting, gage orientation, gage operational error, and gage correction for gas composition are presented in details. The gas composition determination, operating criteria, heavy molecular weight contamination effects, apparent X-ray limit for hot-cathode gages, and cold cathode gages are presented in details.
SCOPE
1.1 This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements below 10−1 N/m2 (10−3 torr) in space-simulation facilities. Since a variety of influences can alter observed vacuum measurements, means of identifying and assessing potential problem areas receive considerable attention. This practice must be considered informational, for it is impossible to specify a means of applying the vacuum-measuring equipment to guarantee accuracy of the observed vacuum measurement. Therefore, the user's judgment is essential so that if a problem area is identified, suitable steps can be taken to either minimize the effect, correct the observed readings as appropriate, or note the possible error in the observation.  
1.2 While much of the discussion is concerned with the application of hot-cathode ionization gages, no exclusion is made of cold-cathode designs. Since a great deal more experience with hot-cathode gages is available and hot-cathode devices are used in the majority of applications, the present emphasis is fully warranted.  
1.3 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This practice describes the standard procedures for providing exposure of thermal control materials to a simulated space environment comprising of the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control. Broad recommendations relating to spectral reflectance measurements, as well as test parameters and other information that should be reported as an aid in interpreting test results are delineated. Specifications are provided for the vacuum system, solar simulator, charged particle sources, safety precautions, and data interpretation.
SCOPE
1.1 This practice describes procedures for providing exposure of thermal control materials to a simulated space environment comprising the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control.  
1.2 Broad recommendations relating to spectral reflectance measurements are made.  
1.3 Test parameters and other information that should be reported as an aid in interpreting test results are delineated.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This practice provides guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles. This practice also provides the proper test environment for systems-integration tests of space vehicles. However, there is no discussion herein of the extensive electronic equipment and procedures required to support such tests. This practice does not apply to or provide incomplete coverage of the following types of tests: launch phase or atmospheric reentry of space vehicles; landers on planet surfaces; degradation of thermal coatings; increased friction in space of mechanical devices, sometimes called "cold welding"; sun sensors; man in space; energy conversion devices; and tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
SCOPE
1.1 Purpose:  
1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles.  
1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing.  
1.2 Nonapplicability—This practice does not apply to or provide incomplete coverage of the following types of tests:  
1.2.1 Launch phase or atmospheric reentry of space vehicles,  
1.2.2 Landers on planet surfaces,  
1.2.3 Degradation of thermal coatings,  
1.2.4 Increased friction in space of mechanical devices, sometimes called “cold welding,”  
1.2.5 Sun sensors,  
1.2.6 Man in space,  
1.2.7 Energy conversion devices, and  
1.2.8 Tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.  
1.3 Range of Application:  
1.3.1 The extreme diversification of space-craft, design philosophies, and analytical effort makes the preparation of a brief, concise document impossible. Because of this, various spacecraft parameters are classified and related to the important characteristic of space simulators in a chart in 7.6.  
1.3.2 The ultimate result of the thermal balance test is to prove the thermal design to the satisfaction of the thermal designers. Flexibility must be provided to them to trade off additional analytical effort for simulator shortcomings. The combination of a comprehensive thermal-analytical model, modern computers, and a competent team of analysts greatly reduces the requirements for accuracy of space simulation.  
1.4 Utility—This practice will be useful during space vehicle test phases from the development through flight acceptance test. It should provide guidance for space simulation testing early in the design phase of thermal control models of subsystems and spacecraft. Flight spacecraft frequently are tested before launch. Occasionally, tests are made in a space chamber after a sister spacecraft is launched as an aid in analyzing anomalies that occur in space.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicabili...

ABSTRACT
This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique. The main elements of the apparatus include a vacuum system, a cold shroud within the vacuum chamber, instrumentation for temperature measurement, and a solar simulator. Any type of coating may be tested by this test method provided its structure remains stable in vacuum over the temperature range of interest. The substrate shall be machined from flat stock and to a size proportioned to the working area of the chamber.
SCOPE
1.1 This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique.  
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
5.1 The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance, or corrections must be made for the specified conditions.  
5.1.1 The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few kelvins.  
5.1.2 The optical path length in the two beams must be equal, or, preferably, the instrument should operate in a nonabsorbing atmosphere, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual-beam instruments becomes very critical.
Note 4: Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrophotometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %.  
5.1.3 Front-surface mirror optics must be used throughout, except for the prism in prism monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings: MgF2 may be used to stabilize mirror surfaces for extended periods of time. The optical characteristics of these coatings are...
SCOPE
1.1 This test method describes an accurate technique for measuring the normal spectral emittance of electrically nonconducting materials in the temperature range from 1000 to 1800 K, and at wavelengths from 1 to 35 μm. It is particularly suitable for measuring the normal spectral emittance of materials such as ceramic oxides, which have relatively low thermal conductivity and are translucent to appreciable depths (several millimetres) below the surface, but which become essentially opaque at thicknesses of 10 mm or less.  
1.2 This test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is particularly suitable for research laboratories, where the highest precision and accuracy are desired, and is not recommended for routine production or acceptance testing. Because of its high accuracy, this test method may be used as a reference method to be applied to production and acceptance testing in case of dispute.  
1.3 This test method requires the use of a specific specimen size and configuration, and a specific heating and viewing technique. The design details of the critical specimen furnace are presented in Ref (1),2 and the use of a furnace of this design is necessary to comply with this test method. The transfer optics and spectrophotometer are discussed in general terms.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in t...

ABSTRACT
These test methods cover determination of the total normal emittance of surfaces by means of portable, inspection-meter instruments. At least two different types of instruments are commercially available for performing this measurement. Test Method A uses an instrument which measures radiant energy reflected from the specimen and Test Method B utilizes an instrument which measures radiant energy emitted from the specimen. Both test methods are limited in accuracy by the degree to which the emittance properties of calibrating standards are known and by the angular emittance characteristics of the surfaces being measure. Test Method A is normally subject to a small error caused by the difference in wavelength distributions between the radiant energy emitted by the two cavities at different temperatures, and that emitted by a blackbody at the specimen temperature. Test Method B also has nongray errors since the detector is not at absolute zero temperature. Test Method A is subject to small errors that may be introduced if the orientation of the sensing component is changed between calibration and specimen measurements. This type of error results from minor changes in alignment of the optical system. Test Method A is subject to error when curved specular surfaces of less than about a certain radius are measured. These errors can be minimized by using calibrating standards that have the same radius of curvature as the test surface. Test Method A can measure reflectance on specimens that are either opaque or semi-transparent in the wavelength region of interest. However, if emittance is to be derived from the reflectance data on a semi-transparent specimen, a correction must be made for transmittance losses. Test Method B is subject to several possible significant errors. These may be due to variation of the test surface temperature during measurements, differences in temperature between the calibrating standards and the test surfaces, changes in orientation of the sensing component between calibration and measurement, errors due to irradiation of the specimen with thermal radiation by the sensing component, and errors due to specimen curvature. Test Method B is limited to emittance measurements on specimens that are opaque to infrared radiation in the wavelength region of interest.
SCOPE
1.1 These test methods cover determination of the total normal emittance (Note 1) of surfaces by means of portable, as well as desktop, inspection-meter instruments.  
Note 1: Total normal emittance (εN) is defined as the ratio of the normal radiance of a specimen to that of a blackbody radiator at the same temperature. The equation relating εN to wavelength and spectral normal emittance [εN(λ)] is
   where:  
  L b(λ, T)   =  Planck's blackbody radiation function = c1λ−5(ec2/λT − 1)−1,    c1   =  3.7415 × 10−16W·m 2,    c2   =   1.4388 × 10−2 m·K,     T  =  absolute temperature, K,    λ  =   wavelength, m,        =  σT4, and     σ   =   Stefan-Boltzmann constant = 5.66961 × 10 −8  W·m−2·K−4    
1.2 These test methods are intended for measurements on large surfaces, or small samples, or both, when rapid measurements must be made and where a nondestructive test is desired. They are particularly useful for production control tests.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ABSTRACT
This test method establishes the apparatuses required, calibration and precision of the devices to be used, and the standard procedures for determining the measured speed, or volumetric flow rate, of oil diffusion pumps. This method shall make use of test dome, gage attachment or connecting line, flow-measuring devices, and leak control valve. The pump under test shall be fitted with a test dome of specified design. Gas is then admitted to the test dome in a specified manner at a measured rate, and the resulting change in equilibrium pressure is measured in the specified way.
SCOPE
1.1 This test method covers the determination of the measured speed (volumetric flow rate) of oil diffusion pumps.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
5.1 The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance:  
5.1.1 The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few degrees Kelvin.  
5.1.2 The optical path length in the two beams must be equal, or the instrument should operate in a nonabsorbing atmosphere or a vacuum, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual beam instruments becomes very critical.
Note 3: Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %; both of these measurements should be reproducible within these limits (see 7.3, Note 6).  
5.1.3 Front-surface mirror optics must be used throughout, except for the prism in prism monochromators and the grating in grating monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings; MgF2 may be used to stabilize mirror surfaces for e...
SCOPE
1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm.  
1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute.  
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
3.1 These practices enable the following information to be available:  
3.1.1 Material atomic oxygen erosion characteristics.  
3.1.2 An atomic oxygen erosion comparison of four well-characterized polymers.  
3.2 The resulting data are useful to:  
3.2.1 Compare the atomic oxygen durability of spacecraft materials exposed to the low Earth orbital environment.  
3.2.2 Compare the atomic oxygen erosion behavior between various ground laboratory facilities.  
3.2.3 Compare the atomic oxygen erosion behavior between ground laboratory facilities and in-space exposure.  
3.2.4 Screen materials being considered for low Earth orbital spacecraft application. However, caution should be exercised in attempting to predict in-space behavior based on ground laboratory testing because of differences in exposure environment and synergistic effects.
SCOPE
1.1 The intent of these practices is to define atomic oxygen exposure procedures that are intended to minimize variability in results within any specific atomic oxygen exposure facility as well as contribute to the understanding of the differences in the response of materials when tested in different facilities.  
1.2 These practices are not intended to specify any particular type of atomic oxygen exposure facility but simply specify procedures that can be applied to a wide variety of facilities.  
1.3 The values stated in SI units are to be regarded as the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice provides guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles. This practice also provides the proper test environment for systems-integration tests of space vehicles. However, there is no discussion herein of the extensive electronic equipment and procedures required to support such tests. This practice does not apply to or provide incomplete coverage of the following types of tests: launch phase or atmospheric reentry of space vehicles; landers on planet surfaces; degradation of thermal coatings; increased friction in space of mechanical devices, sometimes called "cold welding"; sun sensors; man in space; energy conversion devices; and tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
SCOPE
1.1 Purpose:  
1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles.  
1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing.  
1.2 Nonapplicability—This practice does not apply to or provide incomplete coverage of the following types of tests:  
1.2.1 Launch phase or atmospheric reentry of space vehicles,  
1.2.2 Landers on planet surfaces,  
1.2.3 Degradation of thermal coatings,  
1.2.4 Increased friction in space of mechanical devices, sometimes called “cold welding,”  
1.2.5 Sun sensors,  
1.2.6 Man in space,  
1.2.7 Energy conversion devices, and  
1.2.8 Tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.  
1.3 Range of Application:  
1.3.1 The extreme diversification of space-craft, design philosophies, and analytical effort makes the preparation of a brief, concise document impossible. Because of this, various spacecraft parameters are classified and related to the important characteristic of space simulators in a chart in 7.6.  
1.3.2 The ultimate result of the thermal balance test is to prove the thermal design to the satisfaction of the thermal designers. Flexibility must be provided to them to trade off additional analytical effort for simulator shortcomings. The combination of a comprehensive thermal-analytical model, modern computers, and a competent team of analysts greatly reduces the requirements for accuracy of space simulation.  
1.4 Utility—This practice will be useful during space vehicle test phases from the development through flight acceptance test. It should provide guidance for space simulation testing early in the design phase of thermal control models of subsystems and spacecraft. Flight spacecraft frequently are tested before launch. Occasionally, tests are made in a space chamber after a sister spacecraft is launched as an aid in analyzing anomalies that occur in space.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory...

ABSTRACT
This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique. The main elements of the apparatus include a vacuum system, a cold shroud within the vacuum chamber, instrumentation for temperature measurement, and a solar simulator. Any type of coating may be tested by this test method provided its structure remains stable in vacuum over the temperature range of interest. The substrate shall be machined from flat stock and to a size proportioned to the working area of the chamber.
SCOPE
1.1 This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique.  
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements in space-simulation facilities. Acceptable vacuum-measuring equipment shall consist of those items in which performance is compatible with obtaining meaningful measurements. The gage mounting, gage orientation, gage operational error, and gage correction for gas composition are presented in details. The gas composition determination, operating criteria, heavy molecular weight contamination effects, apparent X-ray limit for hot-cathode gages, and cold cathode gages are presented in details.
SCOPE
1.1 This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements below 10−1 N/m2 (10−3 torr) in space-simulation facilities. Since a variety of influences can alter observed vacuum measurements, means of identifying and assessing potential problem areas receive considerable attention. This practice must be considered informational, for it is impossible to specify a means of applying the vacuum-measuring equipment to guarantee accuracy of the observed vacuum measurement. Therefore, the user's judgment is essential so that if a problem area is identified, suitable steps can be taken to either minimize the effect, correct the observed readings as appropriate, or note the possible error in the observation.  
1.2 While much of the discussion is concerned with the application of hot-cathode ionization gages, no exclusion is made of cold-cathode designs. Since a great deal more experience with hot-cathode gages is available and hot-cathode devices are used in the majority of applications, the present emphasis is fully warranted.  
1.3 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

ABSTRACT
This practice describes the standard procedures for providing exposure of thermal control materials to a simulated space environment comprising of the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control. Broad recommendations relating to spectral reflectance measurements, as well as test parameters and other information that should be reported as an aid in interpreting test results are delineated. Specifications are provided for the vacuum system, solar simulator, charged particle sources, safety precautions, and data interpretation.
SCOPE
1.1 This practice describes procedures for providing exposure of thermal control materials to a simulated space environment comprising the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control.  
1.2 Broad recommendations relating to spectral reflectance measurements are made.  
1.3 Test parameters and other information that should be reported as an aid in interpreting test results are delineated.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
5.1 The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance, or corrections must be made for the specified conditions.  
5.1.1 The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few kelvins.  
5.1.2 The optical path length in the two beams must be equal, or, preferably, the instrument should operate in a nonabsorbing atmosphere, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual-beam instruments becomes very critical.Note 4—Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrophotometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %.  
5.1.3 Front-surface mirror optics must be used throughout, except for the prism in prism monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings: MgF2 may be used to stabilize mirror surfaces for extended periods of time. The optical characteristics of these coatings are cr...
SCOPE
1.1 This test method describes an accurate technique for measuring the normal spectral emittance of electrically nonconducting materials in the temperature range from 1000 to 1800 K, and at wavelengths from 1 to 35 μm. It is particularly suitable for measuring the normal spectral emittance of materials such as ceramic oxides, which have relatively low thermal conductivity and are translucent to appreciable depths (several millimetres) below the surface, but which become essentially opaque at thicknesses of 10 mm or less.  
1.2 This test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is particularly suitable for research laboratories, where the highest precision and accuracy are desired, and is not recommended for routine production or acceptance testing. Because of its high accuracy, this test method may be used as a reference method to be applied to production and acceptance testing in case of dispute.  
1.3 This test method requires the use of a specific specimen size and configuration, and a specific heating and viewing technique. The design details of the critical specimen furnace are presented in Ref (1),2 and the use of a furnace of this design is necessary to comply with this test method. The transfer optics and spectrophotometer are discussed in general terms.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This test method establishes the apparatuses required, calibration and precision of the devices to be used, and the standard procedures for determining the measured speed, or volumetric flow rate, of oil diffusion pumps. This method shall make use of test dome, gage attachment or connecting line, flow-measuring devices, and leak control valve. The pump under test shall be fitted with a test dome of specified design. Gas is then admitted to the test dome in a specified manner at a measured rate, and the resulting change in equilibrium pressure is measured in the specified way.
SCOPE
1.1 This test method covers the determination of the measured speed (volumetric flow rate) of oil diffusion pumps.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
3.1 These practices enable the following information to be available:  
3.1.1 Material atomic oxygen erosion characteristics.  
3.1.2 An atomic oxygen erosion comparison of four well-characterized polymers.  
3.2 The resulting data are useful to:  
3.2.1 Compare the atomic oxygen durability of spacecraft materials exposed to the low Earth orbital environment.  
3.2.2 Compare the atomic oxygen erosion behavior between various ground laboratory facilities.  
3.2.3 Compare the atomic oxygen erosion behavior between ground laboratory facilities and in-space exposure.  
3.2.4 Screen materials being considered for low Earth orbital spacecraft application. However, caution should be exercised in attempting to predict in-space behavior based on ground laboratory testing because of differences in exposure environment and synergistic effects.
SCOPE
1.1 The intent of these practices is to define atomic oxygen exposure procedures that are intended to minimize variability in results within any specific atomic oxygen exposure facility as well as contribute to the understanding of the differences in the response of materials when tested in different facilities.  
1.2 These practices are not intended to specify any particular type of atomic oxygen exposure facility but simply specify procedures that can be applied to a wide variety of facilities.  
1.3 The values stated in SI units are to be regarded as the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
0

SIGNIFICANCE AND USE
5.1 The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance:  
5.1.1 The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few degrees Kelvin.  
5.1.2 The optical path length in the two beams must be equal, or the instrument should operate in a nonabsorbing atmosphere or a vacuum, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual beam instruments becomes very critical.Note 3—Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %; both of these measurements should be reproducible within these limits (see 7.3, Note 6).  
5.1.3 Front-surface mirror optics must be used throughout, except for the prism in prism monochromators and the grating in grating monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings; MgF2 may be used to stabilize mirror surfaces for exten...
SCOPE
1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm.  
1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute.  
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
These test methods cover determination of the total normal emittance of surfaces by means of portable, inspection-meter instruments. At least two different types of instruments are commercially available for performing this measurement. Test Method A uses an instrument which measures radiant energy reflected from the specimen and Test Method B utilizes an instrument which measures radiant energy emitted from the specimen. Both test methods are limited in accuracy by the degree to which the emittance properties of calibrating standards are known and by the angular emittance characteristics of the surfaces being measure. Test Method A is normally subject to a small error caused by the difference in wavelength distributions between the radiant energy emitted by the two cavities at different temperatures, and that emitted by a blackbody at the specimen temperature. Test Method B also has nongray errors since the detector is not at absolute zero temperature. Test Method A is subject to small errors that may be introduced if the orientation of the sensing component is changed between calibration and specimen measurements. This type of error results from minor changes in alignment of the optical system. Test Method A is subject to error when curved specular surfaces of less than about a certain radius are measured. These errors can be minimized by using calibrating standards that have the same radius of curvature as the test surface. Test Method A can measure reflectance on specimens that are either opaque or semi-transparent in the wavelength region of interest. However, if emittance is to be derived from the reflectance data on a semi-transparent specimen, a correction must be made for transmittance losses. Test Method B is subject to several possible significant errors. These may be due to variation of the test surface temperature during measurements, differences in temperature between the calibrating standards and the test surfaces, changes in orientation of the sensing component between calibration and measurement, errors due to irradiation of the specimen with thermal radiation by the sensing component, and errors due to specimen curvature. Test Method B is limited to emittance measurements on specimens that are opaque to infrared radiation in the wavelength region of interest.
SCOPE
1.1 These test methods cover determination of the total normal emittance (Note 1) of surfaces by means of portable, as well as desktop, inspection-meter instruments. Note 1—Total normal emittance (εN) is defined as the ratio of the normal radiance of a specimen to that of a blackbody radiator at the same temperature. The equation relating εN to wavelength and spectral normal emittance [εN(λ)] is
1.2 These test methods are intended for measurements on large surfaces, or small samples, or both, when rapid measurements must be made and where a nondestructive test is desired. They are particularly useful for production control tests.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique. The main elements of the apparatus include a vacuum system, a cold shroud within the vacuum chamber, instrumentation for temperature measurement, and a solar simulator. Any type of coating may be tested by this test method provided its structure remains stable in vacuum over the temperature range of interest. The substrate shall be machined from flat stock and to a size proportioned to the working area of the chamber.
SCOPE
1.1 This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice describes the standard procedures for providing exposure of thermal control materials to a simulated space environment comprising of the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control. Broad recommendations relating to spectral reflectance measurements, as well as test parameters and other information that should be reported as an aid in interpreting test results are delineated. Specifications are provided for the vacuum system, solar simulator, charged particle sources, safety precautions, and data interpretation.
SCOPE
1.1 This practice describes procedures for providing exposure of thermal control materials to a simulated space environment comprising the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control.
1.2 Broad recommendations relating to spectral reflectance measurements are made.
1.3 Test parameters and other information that should be reported as an aid in interpreting test results are delineated.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice provides guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles. This practice also provides the proper test environment for systems-integration tests of space vehicles. However, there is no discussion herein of the extensive electronic equipment and procedures required to support such tests. This practice does not apply to or provide incomplete coverage of the following types of tests: launch phase or atmospheric reentry of space vehicles; landers on planet surfaces; degradation of thermal coatings; increased friction in space of mechanical devices, sometimes called "cold welding"; sun sensors; man in space; energy conversion devices; and tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
SCOPE
1.1 Purpose:  
1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles.
1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing.
1.2 Nonapplicability—This practice does not apply to or provide incomplete coverage of the following types of tests:
1.2.1 Launch phase or atmospheric reentry of space vehicles,
1.2.2 Landers on planet surfaces,
1.2.3 Degradation of thermal coatings,
1.2.4 Increased friction in space of mechanical devices, sometimes called “cold welding,”
1.2.5 Sun sensors,
1.2.6 Man in space,
1.2.7 Energy conversion devices, and
1.2.8 Tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
1.3 Range of Application:  
1.3.1 The extreme diversification of space-craft, design philosophies, and analytical effort makes the preparation of a brief, concise document impossible. Because of this, various spacecraft parameters are classified and related to the important characteristic of space simulators in a chart in 7.6.
1.3.2 The ultimate result of the thermal balance test is to prove the thermal design to the satisfaction of the thermal designers. Flexibility must be provided to them to trade off additional analytical effort for simulator shortcomings. The combination of a comprehensive thermal-analytical model, modern computers, and a competent team of analysts greatly reduces the requirements for accuracy of space simulation.
1.4 Utility—This practice will be useful during space vehicle test phases from the development through flight acceptance test. It should provide guidance for space simulation testing early in the design phase of thermal control models of subsystems and spacecraft. Flight spacecraft frequently are tested before launch. Occasionally, tests are made in a space chamber after a sister spacecraft is launched as an aid in analyzing anomalies that occur in space.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations pri...

ABSTRACT
This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements in space-simulation facilities. Acceptable vacuum-measuring equipment shall consist of those items in which performance is compatible with obtaining meaningful measurements. The gage mounting, gage orientation, gage operational error, and gage correction for gas composition are presented in details. The gas composition determination, operating criteria, heavy molecular weight contamination effects, apparent X-ray limit for hot-cathode gages, and cold cathode gages are presented in details.
SCOPE
1.1 This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements below 10−1 N/m2 (10−3 torr) in space-simulation facilities. Since a variety of influences can alter observed vacuum measurements, means of identifying and assessing potential problem areas receive considerable attention. This practice must be considered informational, for it is impossible to specify a means of applying the vacuum-measuring equipment to guarantee accuracy of the observed vacuum measurement. Therefore, the user's judgment is essential so that if a problem area is identified, suitable steps can be taken to either minimize the effect, correct the observed readings as appropriate, or note the possible error in the observation.
1.2 While much of the discussion is concerned with the application of hot-cathode ionization gages, no exclusion is made of cold-cathode designs. Since a great deal more experience with hot-cathode gages is available and hot-cathode devices are used in the majority of applications, the present emphasis is fully warranted.
1.3 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

SIGNIFICANCE AND USE
The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance, or corrections must be made for the specified conditions.
The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few kelvins.
The optical path length in the two beams must be equal, or, preferably, the instrument should operate in a nonabsorbing atmosphere, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual-beam instruments becomes very critical.
Note 4—Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrophotometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %.
Front-surface mirror optics must be used throughout, except for the prism in prism monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings: MgF2 may be used to stabilize mirror surfaces for extended periods of time. The optical characteristics of these coatings are critical, but can be rel...
SCOPE
1.1 This test method describes an accurate technique for measuring the normal spectral emittance of electrically nonconducting materials in the temperature range from 1000 to 1800 K, and at wavelengths from 1 to 35 μm. It is particularly suitable for measuring the normal spectral emittance of materials such as ceramic oxides, which have relatively low thermal conductivity and are translucent to appreciable depths (several millimetres) below the surface, but which become essentially opaque at thicknesses of 10 mm or less.
1.2 This test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is particularly suitable for research laboratories, where the highest precision and accuracy are desired, and is not recommended for routine production or acceptance testing. Because of its high accuracy, this test method may be used as a reference method to be applied to production and acceptance testing in case of dispute.
1.3 This test method requires the use of a specific specimen size and configuration, and a specific heating and viewing technique. The design details of the critical specimen furnace are presented in Ref (1), and the use of a furnace of this design is necessary to comply with this test method. The transfer optics and spectrophotometer are discussed in general terms.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
These test methods cover determination of the total normal emittance of surfaces by means of portable, inspection-meter instruments. At least two different types of instruments are commercially available for performing this measurement. Test Method A uses an instrument which measures radiant energy reflected from the specimen and Test Method B utilizes an instrument which measures radiant energy emitted from the specimen. Both test methods are limited in accuracy by the degree to which the emittance properties of calibrating standards are known and by the angular emittance characteristics of the surfaces being measure. Test Method A is normally subject to a small error caused by the difference in wavelength distributions between the radiant energy emitted by the two cavities at different temperatures, and that emitted by a blackbody at the specimen temperature. Test Method B also has nongray errors since the detector is not at absolute zero temperature. Test Method A is subject to small errors that may be introduced if the orientation of the sensing component is changed between calibration and specimen measurements. This type of error results from minor changes in alignment of the optical system. Test Method A is subject to error when curved specular surfaces of less than about a certain radius are measured. These errors can be minimized by using calibrating standards that have the same radius of curvature as the test surface. Test Method A can measure reflectance on specimens that are either opaque or semi-transparent in the wavelength region of interest. However, if emittance is to be derived from the reflectance data on a semi-transparent specimen, a correction must be made for transmittance losses. Test Method B is subject to several possible significant errors. These may be due to variation of the test surface temperature during measurements, differences in temperature between the calibrating standards and the test surfaces, changes in orientation of the sensing component between calibration and measurement, errors due to irradiation of the specimen with thermal radiation by the sensing component, and errors due to specimen curvature. Test Method B is limited to emittance measurements on specimens that are opaque to infrared radiation in the wavelength region of interest.
SCOPE
1.1 These test methods cover determination of the total normal emittance (Note) of surfaces by means of portable, inspection-meter instruments.
Note 1—Total normal emittance (εN) is defined as the ratio of the normal radiance of a specimen to that of a blackbody radiator at the same temperature. The equation relating εN to wavelength and spectral normal emittance [εN (λ)] is
where:  L b(λ, T) =  Planck's blackbody radiation function = c1π −1λ−5(ec2/λT − 1)−1,  c1 =  3.7415 × 10−16 W·m 2,  c2 =   1.4388 × 10−2 m·K,  T=  absolute temperature, K,  λ=  wavelength, m,  Lb(λ,  T)dλ =  Δπ −1T4, and   Δ =  Stefan-Boltzmann constant = 5.66961 × 10 −8 W·m2·K−4
1.2 These test methods are intended for measurements on large surfaces when rapid measurements must be made and where a nondestructive test is desired. They are particularly useful for production control tests.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance:
The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few degrees Kelvin.
The optical path length in the two beams must be equal, or the instrument should operate in a nonabsorbing atmosphere or a vacuum, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual beam instruments becomes very critical.
Note 3—Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %; both of these measurements should be reproducible within these limits (see 7.3, Note 6).
Front-surface mirror optics must be used throughout, except for the prism in prism monochromators and the grating in grating monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings; MgF2 may be used to stabilize mirror surfaces for extended periods of time. ...
SCOPE
1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm.
1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute.
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 These tables define the solar constant and zero air mass solar spectral irradiance for use in thermal analysis, thermal balance testing, and other tests of spacecraft and spacecraft components and materials. Typical applications include the calculation of solar absorptance from spectral reflectance data and the specification of solar UV exposure of materials during simulated space radiation testing.
1.2 These tables are based upon data from experimental measurements made from high-altitude aircraft, spacecraft, and the earth's surface and from solar spectral irradiance models.
1.3 The values stated in SI units are to be regarded as standard. Other units of measurement are included for information purposes only.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
These practices enable the following information to be available:
3.1.1 Material atomic oxygen erosion characteristics.
3.1.2 An atomic oxygen erosion comparison of four well-characterized polymers.
The resulting data are useful to:
3.2.1 Compare the atomic oxygen durability of spacecraft materials exposed to the low Earth orbital environment.
3.2.2 Compare the atomic oxygen erosion behavior between various ground laboratory facilities.
3.2.3 Compare the atomic oxygen erosion behavior between ground laboratory facilities and in-space exposure.
3.2.4 Screen materials being considered for low Earth orbital spacecraft application. However, caution should be exercised in attempting to predict in-space behavior based on ground laboratory testing because of differences in exposure environment and synergistic effects.
SCOPE
1.1 The intent of these practices is to define atomic oxygen exposure procedures that are intended to minimize variability in results within any specific atomic oxygen exposure facility as well as contribute to the understanding of the differences in the response of materials when tested in different facilities.
1.2 These practices are not intended to specify any particular type of atomic oxygen exposure facility but simply specify procedures that can be applied to a wide variety of facilities.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.3 The values stated in SI units are to be regarded as the standard.

ABSTRACT
This test method establishes the apparatus required, calibration and precision of the devices to be used, and the standard procedures for determining the measured speed, or volumetric flow rate, of oil diffusion pumps. This method shall make use of test dome, gage attachment or connecting line, flow-measuring devices, and leak control valve. The pump under test shall be fitted with a test dome of specified design. Gas is then admitted to the test dome in a specified manner at a measured rate, and the resulting change in equilibrium pressure is measured in the specified way.
SCOPE
1.1 This test method covers the determination of the measured speed (volumetric flow rate) of oil diffusion pumps.
1.2 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice provides guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles. This practice also provides the proper test environment for systems-integration tests of space vehicles. However, there is no discussion herein of the extensive electronic equipment and procedures required to support such tests. This practice does not apply to or provide incomplete coverage of the following types of tests: launch phase or atmospheric reentry of space vehicles; landers on planet surfaces; degradation of thermal coatings; increased friction in space of mechanical devices, sometimes called "cold welding"; sun sensors; man in space; energy conversion devices; and tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
SCOPE
1.1 Purpose
1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles.
1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing.
1.2 NonapplicabilityThis practice does not apply to or provide incomplete coverage of the following types of tests:
1.2.1 Launch phase or atmospheric reentry of space vehicles,
1.2.2 Landers on planet surfaces,
1.2.3 Degradation of thermal coatings,
1.2.4 Increased friction in space of mechanical devices, sometimes called "cold welding,"
1.2.5 Sun sensors,
1.2.6 Man in space,
1.2.7 Energy conversion devices, and
1.2.8 Tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
1.3 Range of Application
1.3.1 The extreme diversification of space-craft, design philosophies, and analytical effort makes the preparation of a brief, concise document impossible. Because of this, various spacecraft parameters are classified and related to the important characteristic of space simulators in a chart in .
1.3.2 The ultimate result of the thermal balance test is to prove the thermal design to the satisfaction of the thermal designers. Flexibility must be provided to them to trade off additional analytical effort for simulator shortcomings. The combination of a comprehensive thermal-analytical model, modern computers, and a competent team of analysts greatly reduces the requirements for accuracy of space simulation.
1.4 UtilityThis practice will be useful during space vehicle test phases from the development through flight acceptance test. It should provide guidance for space simulation testing early in the design phase of thermal control models of subsystems and spacecraft. Flight spacecraft frequently are tested before launch. Occasionally, tests are made in a space chamber after a sister spacecraft is launched as an aid in analyzing anomalies that occur in space.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements in space-simulation facilities. Acceptable vacuum-measuring equipment shall consist of those items in which performance is compatible with obtaining meaningful measurements. The gage mounting, gage orientation, gage operational error, and gage correction for gas composition are presented in details. The gas composition determination, operating criteria, heavy molecular weight contamination effects, apparent X-ray limit for hot-cathode gages, and cold cathode gages are presented in details.
SCOPE
1.1 This practice provides application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements below 101 N/m2 (10 3 torr) in space-simulation facilities. Since a variety of influences can alter observed vacuum measurements, means of identifying and assessing potential problem areas receive considerable attention. This practice must be considered informational, for it is impossible to specify a means of applying the vacuum-measuring equipment to guarantee accuracy of the observed vacuum measurement. Therefore, the user's judgment is essential so that if a problem area is identified, suitable steps can be taken to either minimize the effect, correct the observed readings as appropriate, or note the possible error in the observation.
1.2 While much of the discussion is concerned with the application of hot-cathode ionization gages, no exclusion is made of cold-cathode designs. Since a great deal more experience with hot-cathode gages is available and hot-cathode devices are used in the majority of applications, the present emphasis is fully warranted.
1.3 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

SCOPE
1.1 Purpose
1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles.
1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing.
1.2 NonapplicabilityThis practice does not apply to or provide incomplete coverage of the following types of tests:
1.2.1 Launch phase or atmospheric reentry of space vehicles,
1.2.2 Landers on planet surfaces,
1.2.3 Degradation of thermal coatings,
1.2.4 Increased friction in space of mechanical devices, sometimes called "cold welding,"
1.2.5 Sun sensors,
1.2.6 Man in space,
1.2.7 Energy conversion devices, and
1.2.8 Tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.
1.3 Range of Application
1.3.1 The extreme diversification of space-craft, design philosophies, and analytical effort makes the preparation of a brief, concise document impossible. Because of this, various spacecraft parameters are classified and related to the important characteristic of space simulators in a chart in .
1.3.2 The ultimate result of the thermal balance test is to prove the thermal design to the satisfaction of the thermal designers. Flexibility must be provided to them to trade off additional analytical effort for simulator shortcomings. The combination of a comprehensive thermal-analytical model, modern computers, and a competent team of analysts greatly reduces the requirements for accuracy of space simulation.
1.4 UtilityThis practice will be useful during space vehicle test phases from the development through flight acceptance test. It should provide guidance for space simulation testing early in the design phase of thermal control models of subsystems and spacecraft. Flight spacecraft frequently are tested before launch. Occasionally, tests are made in a space chamber after a sister spacecraft is launched as an aid in analyzing anomalies that occur in space.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This practice describes the standard procedures for providing exposure of thermal control materials to a simulated space environment comprising of the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control. Broad recommendations relating to spectral reflectance measurements, as well as test parameters and other information that should be reported as an aid in interpreting test results are delineated. Specifications are provided for the vacuum system, solar simulator, charged particle sources, safety precautions, and data interpretation.
SCOPE
1.1 This practice describes procedures for providing exposure of thermal control materials to a simulated space environment comprising the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control.
1.2 Broad recommendations relating to spectral reflectance measurements are made.
1.3 Test parameters and other information that should be reported as an aid in interpreting test results are delineated.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 These tables define the solar constant and zero air mass solar spectral irradiance for use in thermal analysis, thermal balance testing, and other tests of spacecraft and spacecraft components and materials. Typical applications include the calculation of solar absorptance from spectral reflectance data and the specification of solar UV exposure of materials during simulated space radiation testing.
1.2 These tables are based upon data from experimental measurements made from high-altitude aircraft, spacecraft, and the earth's surface and from solar spectral irradiance models.
1.3 The values stated in SI units are to be regarded as standard. Other units of measurement are included for information purposes only.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 The intent of these practices is to define atomic oxygen exposure procedures that are intended to minimize variability in results within any specific atomic oxygen exposure facility as well as contribute to the understanding of the differences in the response of materials when tested in different facilities.
1.2 These practices are not intended to specify any particular type of atomic oxygen exposure facility but simply specify procedures that can be applied to a wide variety of facilities.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.3 The values stated in SI units are to be regarded as the standard.

SCOPE
1.1 This test method covers the determination of the measured speed (volumetric flow rate) of oil diffusion pumps.  
1.2 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.  
1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 The purpose of this practice is to provide application criteria, definitions, and supplemental information to assist the user in obtaining meaningful vacuum ionization gage measurements below 10   N/m  (10   torr) in space-simulation facilities. Since a variety of influences can alter observed vacuum measurements, means of identifying and assessing potential problem areas receive considerable attention. This practice must be considered informational, for it is impossible to specify a means of applying the vacuum-measuring equipment to guarantee accuracy of the observed vacuum measurement. Therefore, the user's judgment is essential so that if a problem area is identified, suitable steps can be taken to either minimize the effect, correct the observed readings as appropriate, or note the possible error in the observation.  
1.2 While much of the discussion is concerned with the application of hot-cathode ionization gages, no exclusion is made of cold-cathode designs. Since a great deal more experience with hot-cathode gages is available and hot-cathode devices are used in the majority of applications, the present emphasis is fully warranted.  
1.3 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

SCOPE
1.1 This practice describes procedures for providing exposure of thermal control materials to a simulated space environment comprising the major features of vacuum, electromagnetic radiation, charged particle radiation, and temperature control.
1.2 Broad recommendations relating to spectral reflectance measurements are made.
1.3 Test parameters and other information that should be reported as an aid in interpreting test results are delineated.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 Purpose:  
1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this document should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles.  
1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing.  
1.2 Nonapplicability -This practice does not apply to or provide incomplete coverage of the following types of tests:  
1.2.1 Launch phase or atmospheric reentry of space vehicles,  
1.2.2 Landers on planet surfaces,  
1.2.3 Degradation of thermal coatings,  
1.2.4 Increased friction in space of mechanical devices, sometimes called "cold welding,"  
1.2.5 Sun sensors,  
1.2.6 Man in space,  
1.2.7 Energy conversion devices, and  
1.2.8 Tests of components for leaks, outgassing, radiation damage, or bulk thermal properties.  
1.3 Range of Application:  
1.3.1 The extreme diversification of space-craft, design philosophies, and analytical effort makes the preparation of a brief, concise document impossible. Because of this, various spacecraft parameters are classified and related to the important characteristic of space simulators in a chart in 7.6.  
1.3.2 The ultimate result of the thermal balance test is to prove the thermal design to the satisfaction of the thermal designers. Flexibility must be provided to them to trade off additional analytical effort for simulator short-comings. The combination of a comprehensive thermal-analytical model, modern computers, and a competent team of analysts greatly reduces the requirements for accuracy of space simulation.  
1.4 Utility -This recommended practice will be useful during space vehicle test phases from the development through flight acceptance test. It should provide guidance for space simulation testing early in the design phase of thermal control models of subsystems and spacecraft. Flight spacecraft frequently are tested before launch. Occasionally, tests are made in a space chamber after a sister spacecraft is launched as an aid in analyzing anomalies that occur in space.  
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm.
1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute.
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm.
1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute.
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ABSTRACT
This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique. The main elements of the apparatus include a vacuum system, a cold shroud within the vacuum chamber, instrumentation for temperature measurement, and a solar simulator. Any type of coating may be tested by this test method provided its structure remains stable in vacuum over the temperature range of interest. The substrate shall be machined from flat stock and to a size proportioned to the working area of the chamber.
SCOPE
1.1 This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method covers measurement techniques for calorimetrically determining the ratio of solar absorptance to hemispherical emittance using a steady-state method, and for calorimetrically determining the total hemispherical emittance using a transient technique.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 These test methods cover determination of the total normal emittance (Note) of surfaces by means of portable, inspection-meter instruments. Note 1Total normal emittance (N) is defined as the ratio of the normal radiance of a specimen to that of a blackbody radiator at the same temperature. The equation relating N to wavelength and spectral normal emittance [N()] is
Equation 1 - (See Note 1 and equation in body of E408-71(2002).)1.2 These test methods are intended for measurements on large surfaces when rapid measurements must be made and where a nondestructive test is desired. They are particularly useful for production control tests.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 These test methods cover determination of the total normal emittance (Note) of surfaces by means of portable, inspection-meter instruments. Note 1Total normal emittance (N) is defined as the ratio of the normal radiance of a specimen to that of a blackbody radiator at the same temperature. The equation relating N to wavelength and spectral normal emittance [N()] is
Equation 1 - (See Note 1 and equation in body of E408-71(2002).)1.2 These test methods are intended for measurements on large surfaces when rapid measurements must be made and where a nondestructive test is desired. They are particularly useful for production control tests.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method describes an accurate technique for measuring the normal spectral emittance of electrically nonconducting materials in the temperature range from 1000 to 1800 K, and at wavelengths from 1 to 35 m. It is particularly suitable for measuring the normal spectral emittance of materials such as ceramic oxides, which have relatively low thermal conductivity and are translucent to appreciable depths (several millimetres) below the surface, but which become essentially opaque at thicknesses of 10 mm or less.
1.2 This test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is particularly suitable for research laboratories, where the highest precision and accuracy are desired, and is not recommended for routine production or acceptance testing. Because of its high accuracy, this test method may be used as a reference method to be applied to production and acceptance testing in case of dispute.
1.3 This test method requires the use of a specific specimen size and configuration, and a specific heating and viewing technique. The design details of the critical specimen furnace are presented in Ref (1), and the use of a furnace of this design is necessary to comply with this test method. The transfer optics and spectrophotometer are discussed in general terms.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method describes an accurate technique for measuring the normal spectral emittance of electrically nonconducting materials in the temperature range from 1000 to 1800 K, and at wavelengths from 1 to 35 m. It is particularly suitable for measuring the normal spectral emittance of materials such as ceramic oxides, which have relatively low thermal conductivity and are translucent to appreciable depths (several millimetres) below the surface, but which become essentially opaque at thicknesses of 10 mm or less.
1.2 This test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is particularly suitable for research laboratories, where the highest precision and accuracy are desired, and is not recommended for routine production or acceptance testing. Because of its high accuracy, this test method may be used as a reference method to be applied to production and acceptance testing in case of dispute.
1.3 This test method requires the use of a specific specimen size and configuration, and a specific heating and viewing technique. The design details of the critical specimen furnace are presented in Ref (1), and the use of a furnace of this design is necessary to comply with this test method. The transfer optics and spectrophotometer are discussed in general terms.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This test method covers the measurement of effective pumping speed of complete vacuum-chamber systems. The test method is suitable for all types of vacuum systems operating at pressures below 1 X 10   torr and for chambers larger than approximately 10 ft  (0.3 m ).  
1.2 The values stated in inch-pound units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.