MESSENGER Processing Activities

28 July 2004
The spacecraft was transported July 21 from the Astrotech payload processing facility to Pad 17-B on Cape Canaveral Air Force Station and hoisted atop the Delta II. A spacecraft state-of-health Flight Program Verification, an integrated test of the launch vehicle and the spacecraft, was successfully completed July 24.

The launch weather forecast calls for a 30% chance of not meeting the launch weather criteria on Monday morning. At the 2:16 a.m. launch time the temprature will be near 79 degrees, the relative humidity near 90%, southeast winds at 8-12 knots, the visibility 10 miles or greater. There is a chance of thunderstorms in the vicinity, primarily offshore.

21 July 2004
MESSENGER, riding atop its spacecraft transporter, departed the Astrotech Space Operations facilities in Titusville at 12:27 a.m. today. It arrived at Pad 17-B on Cape Canaveral Air Force Station at 4:40 a.m. and was hoisted atop the Boeing Delta II rocket at 6:20 a.m.

29 June 2004
With the successful launch of the Air Force Delta/GPS mission last week, the launch of NASA's MESSENGER spacecraft has been rescheduled and is now targeted to occur Aug. 2. While the previous launch date of July 30 may have been achievable, the additional margin now being built into the schedule will provide greater confidence in meeting this new launch date.

MESSENGER is undergoing prelaunch testing and final assembly at the Astrotech Space Operations facilities near Kennedy Space Center. Yesterday it was moved to a hazardous processing facility in preparation for loading the spacecraft's complement of hypergolic propellants. Fueling is underway today and will conclude July 1.

The spacecraft's two solar arrays were installed on June 24-25 and a deployment test was conducted. Installation of thermal blankets continues. Spacecraft propellant loading is scheduled for June 29–July 2. Spacecraft spin balance testing is planned for July 7.

Autonomy testing of the spacecraft has been successfully completed and MESSENGER is verified to operate independently when not in direct contact with Earth. The spacecraft Mission Readiness Review was completed on June 24 without any major issues remaining to be resolved.

21 June 2004
The spacecraft’s two solar arrays are undergoing cleaning today in preparation for installation on June 24 -25.  One array will be installed each day.  After an array is installed, a deployment test is conducted.  Installation of thermal blankets continues.  Spacecraft propellant loading is currently scheduled for June 29 – July 2.  Spacecraft spin balance testing is planned for July 7.

Autonomy testing of the spacecraft has been successfully completed.  This verified that MESSENGER can operate on its own when not in direct contact with Earth. 

There are no technical issues or concerns with MESSENGER or its associated Delta II at this time.

The launch period for MESSENGER extends through Aug. 13.

17 June 2004
The two solar arrays will be installed June 23-24 and deployment tests conducted. Installation of the thermal blankets continues.

There are no technical issues or concerns with MESSENGER or the Delta II at this time.

10 June 2004
Autonomy testing of the spacecraft has been successfully completed. Installation of thermal blankets continues.

The solar arrays will be installed June 21, followed by release tests on June 23-24. Spacecraft propellant loading is scheduled for June 28-July2. Spacecraft spin balance testing is planned for July 7 and mating to the upper stage booster will occur July 12. The spacecraft will leave Astrotech for Cape Canaveral Air Force Station on July 16 and be mated to the Delta II rocket at Pad 17-B.

26 May 2004
In upcoming work, the flight battery is scheduled for installation June 8 and the solar arrays will be installed June 22.

20 May 2004
MESSENGER continues to undergo prelaunch testing at the Astrotech space Operations facilities near Kennedy Space Center. Autonomy testing is ongoing.

29 April 2004
MESSENGER is at the Astrotech Space Operations facilities near Kennedy Space Center, where it is undergoing prelaunch testing.

Testing of the spacecraft's radio system uplink and downlinks though the KSC/JPL interface with Deep Space Network (MIL-71) has been successfully completed. Autonomy testing continues. This verifies MESSENGER's ability to operate on its own when not in direct contact with Earth. Installation of thermal blankets has been completed as required on the schedule up to this time.

15 April 2004
The spacecraft was moved from its current location on Tuesday. The remainder of its final assembly and testing will be completed there. The spacecraft will return to the hazardous processing facility when ready for fueling, spin balance testing and mating to the upper stage.

8 April 2004
Testing of the spacecraft’s radio system uplink and downlinks through the KSC/JPL interface with the Deep Space Network (MIL-71) continues. Autonomy testing is also continuing.

On April 13, the spacecraft will be moved from its current location in the hazardous processing facility, where it has been since arrival, to an adjacent non-hazardous payload processing facility.

31 March 2004
Testing of the spacecraft's radio system uplink and downlinks through the KSC/JPL interface with the Deep Space Network is underway. This testing will last about ten days. Autonomy testing is also underway. This verifies MESSENGER's ability to operate on its own when not in direct contact with Earth. Installation of thermal blankets continues.

24 March 2004
A decision has been made to reschedule the launch of NASA's MESSENGER spacecraft to no earlier than July 30. The launch opportunity extends until Aug. 13, 2004.

Several factors led to NASA's decision to move the launch from its original May 11 date, including a desire to include more testing of MESSENGER's fault-protection system software. This allows the spacecraft to check its own health and, when necessary, switch between alternative backup systems. This will also create some additional time for the test team to complete final assembly and checkout affording a more comfortable spacecraft processing schedule.

The spacecraft will continue its processing activities at the Astrotech Space Operations facilities near Kennedy Space Center.

17 March 2004
The MESSENGER spacecraft arrived at the Astrotech Space Operations processing facility near Kennedy Space Center on March 10. It was offloaded and taken into a high bay clean room. The soft covers were then removed, and the spacecraft was hoisted onto a test stand and powered-up the same day. Post-arrival state-of-health checks were successfully completed.

Processing for launch began this week, including checkout of the power systems, communications systems and control systems. Workers are also beginning to attach the thermal blankets to the spacecraft for flight.

10 March 2004
MESSENGER arrived in Florida and was taken to processing facilities near Kennedy Space Center where it was offloaded and taken into a high bay clean room.

After the spacecraft is removed from its shipping container it will undergo an initial state-of-health check. Processing for launch can then begin including checkout of the power systems, communications systems and control systems. The thermal blankets will also be attached for flight.

Installation of the two solar arrays will occur in mid-April and then the arrays will undergo a deployment test.

5 March 2004
MESSENGER is out of the thermal vacuum chamber after five weeks of rigorous environmental tests. Engineers baked the sunshade to about 350 degrees Celsius (662 degrees Fahrenheit) without a problem, and the spacecraft showed it could withstand the wide range of hot and cold temperatures it will face.

23 Feb 2004
MESSENGER is set to be removed from the thermal-vacuum chamber this week, having passed the battery of hot-and-cold cycling tests that prepare it for the space environment. Final tweaks to the spacecraft will be performed over the following two weeks, and then MESSENGER is headed to Kennedy Space Center/Cape Canaveral for final launch preparations.

30 Jan 2004
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 a four-story chamber late last week and 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.

22 Jan 2004
MESSENGER has undergone extensive prelaunch testing. 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.

15 Jan 2004
MESSENGER has undergone a spin balance test. The test is critical to the spacecraft's early operations: the third (and final) stage of MESSENGER's Delta II launch vehicle is spin stabilized, so both spacecraft and rocket must be balanced to fly straight.

In this test, engineers measured MESSENGER's center of gravity by spinning it to 25 rpm on its "z" axis. The testing machines then showed the team where to place weights on the spacecraft to balance it on this middle line. Engineers conducted spin balance tests with MESSENGER's tanks both empty and filled with water (to simulate fuel).

7 Jan 2004
One of MESSENGER's first tasks after arriving at NASA's Goddard Space Flight Center last month was acoustic vibration testing, which measures the spacecraft's ability to withstand the sound-induced shaking during launch. Very powerful speakers were set up around the spacecraft in Goddard's reverberant acoustic chamber and engineers cranked the volume of a fumbling roar sound past 140 decibels - louder than a jet engine. MESSENGER came through the acoustic test unscathed.