Spaceflight Now Home





Mission Reports




For 11 years, Spaceflight Now has been providing unrivaled coverage of U.S. space launches. Comprehensive reports and voluminous amounts of video are available in our archives.
Space Shuttle
Atlas | Delta | Pegasus
Minotaur | Taurus | Falcon
Titan



NewsAlert



Sign up for our NewsAlert service and have the latest space news e-mailed direct to your desktop.

Enter your e-mail address:

Privacy note: your e-mail address will not be used for any other purpose.



Advertisement






Space Books






Mars Express back in business at the red planet
BY STEPHEN CLARK
SPACEFLIGHT NOW

Posted: February 15, 2012


Bookmark and Share

Europe's Mars Express resumed full science operations in early February, four months after scientists suspended research following persistent glitches in the probe's solid-state mass memory unit, according to the craft's mission manager.


Artist's concept of Mars Express. Credit: ESA
 
"Mars Express has now been restored to full operational capability and its potential mission lifetime remains unchanged," a European Space Agency statement said.

Problems with the 12-gigabit memory unit, which contains data and commands necessary for instrument operations, put Mars Express in safe mode four times. The data system is required for the spacecraft to conduct scientific reesearch, storing up to 50 individual commands for each observation.

The safe mode events forced Mars Express to rapidy point toward the sun, consuming six months' worth of propellant in a short time, according to ESA.

After the data storage glitch showed up using two redundant controllers, engineers halted scientific observations Oct. 16 to avoid burning more propellant and preserve the mission's expected lifetime.

Officials turned to a hardware-based timeline store in a different computer, bypassing the issue believed to have caused the safe modes last year.

But the backup timeline store can only hold 117 commands, much less than the thousands executable in the timeline in the faulty solid-state mass memory unit.

Engineers found a way to write much shorter command sequences to fit in the hardware-based short timeline, and although the suspect memory unit continues to experience errors, none of them have triggered a safe mode, according to ESA.

"This has recently been tested in real life, as the spacecraft encountered a [solid-state memory unit] anomaly exactly like those in late 2011, but this time was able to complete the observation and return to Earth pointing without entering safe mode," an ESA statement said. "This allowed a much faster recovery to nominal operations and avoided wasting precious propellant."

Controllers continue working on a command scheduler to allow Mars Express to function autonomously for up to a week, reducing the workload for ground operators.

Fred Jansen, Mars Express mission manager, said the spacecraft has more than 8 pounds of maneuvering propellant left in its tank, which should be enough fuel to continue the mission for up to 14 more years.

STS-134 Patch

Free shipping to U.S. addresses!

The final planned flight of space shuttle Endeavour is symbolized in the official embroidered crew patch for STS-134. Available in our store!
 U.S. STORE
 WORLDWIDE STORE

Final Shuttle Mission Patch

Free shipping to U.S. addresses!

The crew emblem for the final space shuttle mission is now available in our store. Get this piece of history!
 U.S. STORE
 WORLDWIDE STORE

Apollo Collage
This beautiful one piece set features the Apollo program emblem surrounded by the individual mission logos.
 U.S. STORE

STS-133 Patch

Free shipping to U.S. addresses!

The final planned flight of space shuttle Discovery is symbolized in the official embroidered crew patch for STS-133. Available in our store!
 U.S. STORE
 WORLDWIDE STORE

Anniversary Shuttle Patch

Free shipping to U.S. addresses!

This embroidered patch commemorates the 30th anniversary of the Space Shuttle Program. The design features the space shuttle Columbia's historic maiden flight of April 12, 1981.
 U.S. STORE
 WORLDWIDE STORE

Mercury anniversary

Free shipping to U.S. addresses!


Celebrate the 50th anniversary of Alan Shephard's historic Mercury mission with this collectors' item, the official commemorative embroidered patch.
 U.S. STORE
 WORLDWIDE STORE

INDEX | PLUS | NEWS ARCHIVE | LAUNCH SCHEDULE
ASTRONOMY NOW | STORE

ADVERTISE

© 2014 Spaceflight Now Inc.