Slight Hiccup For Opportunity Before Getting To 'Erebus Crater'

MARSDAILY

This is a mosaic assembled from some of the images taken by the panoramic camera on NASA's Opportunity during the rover's 590th sol (Sept. 21, 2005). The view is toward the south and includes rock exposures north of "Erebus Crater," with the crater in the background.

Pasadena CA (SPX) Oct 05, 2005
Opportunity suffered a warm reboot last week. After the flight computer rebooted, the spacecraft went into "safe mode." This error caused the team to miss two Odyssey passes.

The evening pass was missed because the reboot occurred during the Odyssey pass. The morning pass was missed because safe mode enforces the deep sleep behavior.

Real-time commands were sent on sol 597 in order to access the state of the vehicle. Opportunity was healthy and the team regained control of the vehicle. A "lite" master sequence was loaded and sol 597 became a stand down day. On sol 598, the initial system recovery steps were taken and subsystems were tested. All subsystems look good.

This is the first time this fault has been seen on Opportunity. It was seen twice before on Spirit, in May and August of 2004. The decision at that time was to not fix the software bug that causes this problem, and accept the rare interruptions in operations.

The bug is a window of vulnerability in the process of lifting memory write protects and replacing them. The bug allows a 51 microsecond window where another write request can interrupt the first request. When the writes collide, the software protects itself and the vehicle by terminating activities.

This week Opportunity will continue with nominal operations. The rover will continue to move west around Erebus Crater.

Sol-by-sol summaries

Sol 592: Drove 1.75 meter (69 inches) and approached target "Deception" on the feature "South Shetland."

Sol 593: Unstowed the robotic arm, used rock abrasion tool brush, took a stereo microscopic image and then placed the alpha particle X-ray spectrometer.

Sol 594: Continued the robotic arm campaign. Placed the alpha particle X-ray spectrometer, then changed tool to the Moessbauer spectrometer.

Sol 595: Continued the robotic arm campaign. Placed alpha particle X-ray spectrometer on new target then change tool to the Moessbauer spectrometer on the next sol.

Sol 596: Anomaly - warm reboot day.

Sol 597: Stand-down day.

Sol 598: Recovery day, subsystem testing.

MARSDAILY

Mars Rovers May Yet Make Major Discoveries

Washington (UPI) Oct 03, 2005
NASA scientists in Washington have stopped making predictions about the Mars rovers Spirit and Opportunity as the devices continue to navigate across Mars.

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.