NASA MESSENGER Status Report January 17, 2005

Camera Check: Nominal cruise operations continued over the past week. On Jan. 12, the science, engineering and mission operations teams successfully conducted the second absolute radiometric calibration for the Mercury Dual Imaging System (MDIS) instrument. Repeating an exercise conducted last Nov. 29, operators tilted the spacecraft 27 degrees so the camera could image sunlight reflected off a target inside the payload attachment fitting, which surrounds MDIS and three other science instruments on MESSENGER’s lower deck.

“The operation went very smoothly,” reports Mission Operations Manager Mark Holdridge, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.

Other activities included turning on the backup Integrated Electronics Module for routine housekeeping operations.

Stat Corner: MESSENGER is about 94.4 million miles (152 million kilometers) from the Sun and 30.2 million miles (48.7 million kilometers) from Earth. At that distance, a signal from Earth reaches the spacecraft in 2 minutes, 42 seconds. The spacecraft is moving around the Sun at 65,538 miles (105,473 kilometers) per hour. MESSENGER’s onboard computers have executed 25,230 commands from mission operators since launch.