Space temperature traceability based on near-site transfer of miniature fixed points

Area of Science:

• Space physics and remote sensing instrumentation.
• Metrology and calibration techniques.
• Materials science for extreme environments.

Background:

• Long-term remote sensing precision requires real-time radiation calibration.
• Spaceborne calibrators face stability and accuracy challenges in harsh space environments.
• Miniature fixed points offer International System of Units traceability for space radiation values, but in-situ methods struggle with location mismatches.

Purpose of the Study:

• To demonstrate a space temperature traceability technology for continuous, all-location self-calibration.
• To establish a transfer link between fixed points, blackbody, and remote sensors.
• To provide effective on-orbit traceability for long-term remote sensing.

Main Methods:

• Developed a near-site transfer mechanism utilizing phase transition characteristics for temperature self-calibration.
• Established a traceability chain connecting fixed points, a spaceborne blackbody, and remote sensors.
• Deployed eight miniature fixed points across a temperature range of 234 K to 345 K.

Main Results:

• Achieved repeatability and long-term stability of 6.0 mK and 3.2 mK, respectively.
• Demonstrated the latest spaceborne blackbody with the first on-orbit replication of 7.4 mK.
• Validated a continuous temperature self-calibration technology across diverse locations.

Conclusions:

• The demonstrated space temperature traceability technology enables effective on-orbit calibration.
• This approach overcomes limitations of traditional in-situ methods for space radiation monitoring.
• The technology enhances the accuracy and reliability of long-term remote sensing missions.