Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty

Headshot of Emily Lakdawalla

Arizona Daily Star reports MRO managers working to avoid "unlikely but potentially fatal scenario"

Posted by Emily Lakdawalla

28-10-2009 13:53 CDT


Mars Reconnaissance Orbiter has been in safe mode for nine weeks, since August 26, the date of the fourth in a series of safing events. A JPL update on the situation dated to September 4 said that analysis had "identified one possible but unlikely scenario jeopardizing the spacecraft. This scenario would require two computer resets, each worse than any so far, occurring within several minutes of each other in a certain pattern." Today's Arizona Daily Star contains a bit more information on this possible failure scenario:

While the engineers have not been able to find the root cause of why the orbiter [rebooted] on Aug. 26, they are seeing a pattern among the four occurrences this year.

"In all four cases the most likely scenario is that ... either one of the voltages wasn't right or the part of the device that measures voltages indicated there was a problem and there wasn't one," [project manager Jim] Erickson said.

The unclear voltage signals have caused the orbiter in one instance to switch to a backup computer and in the three other instances to reset the computer. Engineers worry that if these actions happen in a short enough time frame, the memory of the main computer as well as the memory of the backup computer could be reset.

"There's a case where the spacecraft may not remember that it is in mapping mode," Erickson said. "It might think it's on the ground waiting to be turned on."

Engineers are now working to create a safeguard against that worst-case scenario as well as finding the cause of the mysterious voltage signals.

Since they haven't figured out a cause yet, it's no surprise that Erickson can't currently give a date as to when MRO will be able to return to normal operations. Now that it's in its extended mission, its highest priority is to serve as a communications relay for future landers -- I wonder if there are possible recovery scenarios that include return to relay operations but not return to science? We'll have to wait for further updates to come out of the mission.

Meanwhile, spring continues to arrive to Mars' northern plains...

MRO in Orbit


MRO in Orbit

See other posts from October 2009


Or read more blog entries about:


Leave a Comment:

You must be logged in to submit a comment. Log in now.
Facebook Twitter Email RSS AddThis

Blog Search


Election 2016

Space rarely makes a strong showing in national elections, despite the major state of transition NASA finds itself in today.

Help us catalog and source statements made by candidates referring to civil space issues.

Learn More

Featured Images

Titan's south polar vortex
Titan's haze
Dione from Rev 177
Saturn's hexagon
More Images

Featured Video


Watch Now

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Join the New Millennium Committee

Let’s invent the future together!

Become a Member

Connect With Us

Facebook, Twitter, YouTube and more…
Continue the conversation with our online community!