Since leaving "home" at the Applied Physics Laboratory on Dec. 19, MESSENGER has undergone extensive prelaunch testing at NASA Goddard Space Flight Center. From spin balance checks to mass properties measurements to launch-vibration simulations, the tests are proving that the spacecraft can withstand the rigors of liftoff and the space environment.
This week the spacecraft will be sealed inside Goddard's large thermal vacuum chamber, where for the next month it will be cycled through the range of temperatures it will face in flight. Temperature extremes will vary in the chamber near different parts of the spacecraft, from a high of 325 Celsius (or 617 Fahrenheit, at the sunshade) down to minus-180 C (or minus-292 F, near MESSENGER's top and bottom decks).
In this image from January 11, an engineer installs and checks some of the hundreds of temperature sensors - called thermocouples - placed on the spacecraft for the thermal vacuum tests. (Click here for a large or small time-lapse movie of the activity.) The team had removed MESSENGER's sunshade on January 9 to gain better access to the spacecraft for the installation.
Last updated: January 22,