The MESSENGER spacecraft is now in a thermal vacuum test chamber at the Goddard Space Flight Center, proving its ability to weather the extreme environment it will encounter at Mercury.
In the chamber, the spacecraft is subjected to vacuum conditions (all the air is pumped out) and a wide range of hot and cold temperatures. MESSENGER was sealed off in the four-story chamber late last week; over the past few days a large panel of heating rods has been roasting MESSENGER's ceramic-fabric sunshade to temperatures above 350 degrees Celsius (662 Fahrenheit). The team doesn't expect the sunshade to get this hot during the mission, but they do want to make sure there is plenty of margin to avoid any surprises down the road.
In this frame, snapped from the Webcam on Jan. 20, an engineer installs a few of the 50 thermocouples to the sunshade before the thermal vacuum tests. Thermocouples are small temperature sensors made by joining two different metals, giving the engineers exact temperature readings from key spots on the sunshade. The coils are connecting wires for the thermocouples, awaiting installation to a data-collection computer.
Last updated: January 30,