Thermal Engineering

On the Magellan radar-mapping mission to Venus, some portions of the spacecraft, which faced the sun, reached temperatures close to the boiling point of water. At the same time, the side facing space remained a few degrees above absolute zero (-273oC). Since convection does not work to equalize temperatures in a vacuum, Northrop Grumman IT personnel supported the analysis and review of extraordinary Magellan design measures to keep sensitive instruments and electronics within their operating temperature range.

Our staff has used complex computer programs to characterize the thermal balance from external and internal (electronics) heat sources in a given orbit. The use of thermal control measures, such as multi-layer insulation blankets, thermal control coatings, and radiator surfaces, are all considered in the design. Failures, anomalies, and glitches during testing are analyzed, and corrective actions are considered.

For example, we helped define the thermal-vacuum test requirements for Topex, a mission to conduct precise measurements of ocean surface topography. We developed photograph-enhancing algorithms to correct for aberrations in the Hubble Space Telescope, and we provided environmental and reliability support for design of a replacement to the Hubble's Wide-Field Planetary Camera.

The Galileo program imposed severe operational constraints upon the spacecraft. When the Galileo Probe plunged into Jupiter's dense atmosphere, the heat shield protecting sensitive instruments and radio equipment was heated to twice the temperature of the surface of the sun. Northrop Grumman staff received multiple NASA awards for our work on instrument design and on monitoring the spacecraft and probe throughout the mission. Galileo provided valuable clues to the composition of the gas giant - and to the origin of the universe.