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

Very brief Curiosity update, sol 205: Memory anomaly and a swap to the "B-side"

Posted by Emily Lakdawalla

04-03-2013 18:48 CST

Topics: mission status, Curiosity (Mars Science Laboratory)

Hopefully many of you have been following Curiosity's mission to Mars through the rapid release of its raw images. But there haven't been any new images since sol 200 because the mission has been working its way through its first major (not life-threatening, just really inconvenient) anomaly: a memory problem in its main computer. I will let other outlets attempt to explain what's known about the bad news, like National Geographic and CBS News. JPL just announced that they brought the rover out of safe mode on its backup set of electronics, and that they've resumed communication using the high-gain antenna, but that they still need a few days to perform housekeeping operations before they can resume science activity.

Since landing, Curiosity has been employing its "A-side" set of electronics. It has a fully redundant set of electronics, the "B-side," with some connections between the two that would, in theory, permit its controllers to use some parts of A with some parts of B, but for the most part the preferred way of doing things is to have one side running the show and the other side available as a backup. With this swap to the B-side, then, Curiosity's B-side electronics will be considered the main system and the A-side the backup. They'll continue to work on fixing the memory problem on the A-side while they rely on the B-side for operations.

One of the things that'll make the switch a little bit interesting is that it's not just the brains that are redundant; the B-side computers are connected to a second set of engineering cameras that haven't been used yet, as far as I know. Curiosity's new point of view out its B cameras will produce a very slight shift in the perspective of Navcam panoramas (the B cameras are just below the A cameras but have the same horizontal position with respect to the mast). There will be a much larger shift in the perspective of Hazcam views.

Locations of Curiosity's cameras


Locations of Curiosity's cameras
Locations of all of Curiosity's cameras: the two Mastcams; Chemcam Remote Micro-Imager (RMI); the left and right Navcams (set A, used from landing, on top, and set B, used after the A-side anomaly, on the bottom); the left and right front Hazcams (in A-B-A-B order, so that pair A has a view that is shifted slightly to the right of pair B, but they overlap); and the left and right rear Hazcams (with pair A located on the port side and pair B located on the starboard side, so that pair A has a point of view shifted to the right with respect to pair B's point of view).
Curiosity's forward Hazard Avoidance Cameras (Hazcams) as seen from MAHLI, sol 34

NASA / JPL / MSSS / Emily Lakdawalla

Curiosity's forward Hazard Avoidance Cameras (Hazcams) as seen from MAHLI, sol 34
On sol 33, Curiosity used its Hand Lens Imager (MAHLI) to take the first views of previously unseen parts of the rover, including the two pairs of Hazard Avoidance Cameras (Hazcams). Curiosity uses only one pair at a time. On sol 33, Curiosity was using the first and third of these (images from these two have filenames beginning with "FRA" and "FLA"); the second and fourth form a backup pair attached to the B-side computer ("FRB" and "FLB").

The lack of new images from Curiosity's side of Mars has given me time to explore the goodies among the mission's first release of archival data to the Planetary Data System. I'll have more on that later this week, but feel free to explore it for yourselves! Or just explore this cool interactive 3D panorama of the landing site, produced by Andrew Bodrov.

See other posts from March 2013


Or read more blog entries about: mission status, Curiosity (Mars Science Laboratory)


Pessimist: 03/05/2013 02:27 CST

The extremely long deployement time poses a very high risk for total malfunction before any really useful science can be done. It has been over half a year now, and it isn't any closer to its target area. Its instruments have only just been somewhat tested. All this should have been done during the first couple of weeks after landing. The extreme prolongation of non-science-administration before the beginning of the real mission, has drastically increased the risk for total mission failure before completion. I fear that the whole mission has been completely misplaned from the very beginnings. It will certainly take much more than another year before the rover reachers its target, even according to plan. Changes might be very slim that it manages to do that.

Gerald: 03/06/2013 09:40 CST

@Pessimist: The currently investigated Yellowknife Bay region looks unexpectedly interesting. Although it's not yet the originally intended target, it's of scientific value on its own. A lot of science is already done, most of it not yet fully evaluated and published. So the notion "risk of total mission failure" looks inappropriate to me. I'd propose to take a look at the LPSC this month, where a lot of results will be presented.

Leave a Comment:

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

Blog Search

Planetary Defense

An asteroid or comet headed for Earth is the only large-scale natural disaster we can prevent. Working together to fund our Shoemaker NEO Grants for astronomers, we can help save the world.


Featured Images

LightSail 2 and Prox-1
Bill Nye at LightSail 2 pre-ship review
LightSail 2 pre-ship review team photo
Swirling maelstrom
More Images

Featured Video

Class 9: Saturn, Uranus, and Neptune

Watch Now

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Join The Planetary Society

Let’s explore the cosmos together!

Become a Member

Connect With Us

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