Mars Rovers Continue Exploration

Aug 05, 2004
Mars Rovers Continue Exploration

NASA's Spirit rover has climbed higher into rocky hills on Mars, and its twin, Opportunity, has descended deeper into a crater, but both rovers, for the time being, are operating with some restrictions while team members diagnose unexpected behavior.

Both rovers have successfully operated for more than double the span of their three-month primary missions. They have been conducting bonus science in extended missions since April.

While Spirit was executing commands on Aug. 1, a semiconductor component failed to power on as intended. The component, a programmable gate array, directly affects usability of the rover's three spectrometer instruments. Subsequent commands for using the miniature thermal emission spectrometer in that day's sequence resulted in repeated error messages.

Engineers on the Mars Exploration Rover team at NASA's Jet Propulsion Laboratory, Pasadena, Calif., have determined the most likely cause is a timing issue of one instruction reaching the gate array microseconds before another that was intended to precede it. If that diagnosis is confirmed, a repeat could be avoided by inserting a delay between commands that might reproduce the problem, engineers expect. Until then, the rover science team's daily choices for how to use Spirit do not include using the miniature thermal emission spectrometer, the Moessbauer spectrometer or the alpha particle X-ray spectrometer.

"While we're being very cautious in how we operate today and tomorrow, we expect to verify the problem and resolve this issue with a relatively easy workaround," said JPL's Jim Erickson, project manager for the twin rovers.

Spirit has driven to a bedrock exposure near the top of a spur of the "Columbia Hills." The location sits about nine meters (30 feet) above a plain that the rover crossed for months to get from its landing site to the hills. Planners intend for Spirit to spend more than a week at this site, inspecting the rock exposure, dubbed "Clovis," and recording the panoramic scene from this viewpoint.

Halfway around Mars, Opportunity has driven about 20 meters (66 feet) into "Endurance Crater," examining increasingly older layers of bedrock as it advances. If assessments of traversability continue giving positive indications, the rover team plans next to send Opportunity counterclockwise across the inner slope of the crater to study possible targets of dune tendrils, boulders and the base of a cliff.

Four times in the past two weeks, Opportunity has sent error messages while successfully taking pictures with its microscopic imager. One theory for the cause is degradation of flexible cabling that runs down the rover's robotic arm to the instrument. As a precaution while undertaking further analysis, the rover team is treating use of the arm as a consumable resource, with cable wear each time the arm is moved decreasing the possible number of future microscopic images.

"We are being very conservative about this because we certainly don't want to do anything to jeopardize the instruments," said Dr. Ken Herkenhoff of the U.S. Geological Survey Astrogeology Team, Flagstaff, Ariz., lead scientist for both rovers' microscopic imagers. "We are running more diagnostics that we hope will identify the problem. There are potential explanations that would mean we do not have to treat arm use as a consumable."

Erickson said, "We will no doubt have more issues with them in the future. We'll do everything we can to milk the most value out of them while they are usable, but they won't last forever."

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Science Mission Directorate, Washington. Additional information about the project is available from JPL at marsrovers.jpl.nasa.gov/ and from Cornell University, Ithaca, N.Y., at athena.cornell.edu.

Source: NASA

Explore further: 'Space bubbles' may have aided enemy in fatal Afghan battle

add to favorites email to friend print save as pdf

Related Stories

Scientists work to free Mars rover Spirit

Oct 13, 2009

(PhysOrg.com) -- In the past several weeks, scientists at NASA's Jet Propulsion Laboratory finished experimentation on methods to get the rover Spirit unstuck from its location near a plateau called Home Plate.

Opportunity peers out from 'Pillinger Point'

Jun 17, 2014

NASA's decade old Opportunity rover has reached a long sought after region of aluminum-rich clay mineral outcrops at a new Endeavour crater ridge now "named 'Pillinger Point' after Colin Pillinger the Principal ...

NASA solves mystery of Mars 'doughnut' rock

Feb 15, 2014

NASA scientists were finally able to explain the origin of the mysterious rock shaped like a jelly doughnut that appeared near the rover Opportunity in early January.

Curiosity crosses Dingo Gap dune

Feb 10, 2014

NASA's Curiosity mega rover has successfully crossed over the 'Dingo Gap' sand dune- opening the gateway to the science rich targets in the "Moonlight Valley" and Martian mountain beyond.

Mars rover, slightly used, runs fine

Feb 05, 2014

(Phys.org) —When a car gets regular oil changes and care from a good mechanic, keeping it running for 10 years or more isn't exactly an impressive feat of engineering. But then again, such a car isn't an ...

Recommended for you

Getting to the root of the problem in space

4 hours ago

When we go to Mars, will astronauts be able to grow enough food there to maintain a healthy diet? Will they be able to produce food in NASA's Orion spacecraft on the year-long trip to Mars? How about growing ...

The difference between CMEs and solar flares

7 hours ago

This is a question we are often asked: what is the difference between a coronal mass ejection (CME) and a solar flare? We discussed it in a recent astrophoto post, but today NASA put out a video with amazing graphics that explain ...

Scientific instruments of Rosetta's Philae lander

7 hours ago

When traveling to far off lands, one packs carefully. What you carry must be comprehensive but not so much that it is a burden. And once you arrive, you must be prepared to do something extraordinary to make ...

Image: NGC 6872 in the constellation of Pavo

8 hours ago

This picture, taken by the NASA/ESA Hubble Space Telescope's Wide Field Planetary Camera 2 (WFPC2), shows a galaxy known as NGC 6872 in the constellation of Pavo (The Peacock). Its unusual shape is caused ...

User comments : 0