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Page 1: For Mars lander scientists, nothing to say but it’s OKsirius.bu.edu/withers/media/mer/usatoday20040105.pdfJan 05, 2004  · ppp Tired but ecstatic, scientists began ex-ploring their

Rover’srotationalsix-wheeldrive

By moving the front wheels in andback wheels out, the rover canrotate on a dime. The centerwheels are drive only.

TOP VIEW

Roaming rovers

Movements and agility

Sources: NASA, JPL, Florida Today, GNS research

Minithermalemissionspectrometer (at rear)Records the thermal spectra of variousrocks and soils, including infrared.

Panoramiccameras

By Jerald Council, Jef Dauber and Janet Loehrke, Gannett News Service

Mössbauer spectrometerChecks for composition ofiron-bearing minerals in rock.

Rock abrasion tool (RAT)Grinds rock to remove dustand weathered rock.

Magnet arraysCollect airborne dustfor analysis.

High-gain antennaDish points toward Earth to communicatewith Deep Space Network.

Solar arraysProvide power for driving the rover, operating thescience instruments, heating the electronics boxand recharging batteries.

Alpha particle X-rayspectrometerChecks for elements thatmake up rocks and soils.

MicroscopicimagerProduces close-upviews of rocksand soils todetermine theircharacteristics.

Rocker-bogiemobility systemEach wheel has an independentmotor allowing easy mobility.

Warm electronics boxBody of the rover is a heatedcontainer that protects vitalelectronics.

Calibration targetsFine-tunes observationsfrom imagers and scienceinstruments.

Navigation camerasImages help scientists decidewhat rock and soils toanalyze.

Panoramic camerasProvides high-resolution color panoramas of theMartian surface. Its resolution is more than threetimes more powerful than previous rovers’. Imageswill help select rock and soil targets for future study.

After six months and 25 days,the first Mars explorationrover has arrived on Mars.

4-foot-9-inchrover

Though it can withstand a 45-degree tilt without overturning,the rover has 30-degree limita-tions in its programming.

The suspension allows the roverto minimize rocking as it travels,and safeguards its instrumentsfrom shock.

Top speed for the rover is a cau-tious 2 inches per second, allow-ing scientists to select the safestroute.

Rover scans for surface hazardsand gathers data to transmit toEarth. It moves for 10 seconds,stops and studies for 20 seconds.

Scientists based in NASA’s JetPropulsion Laboratory in Pasadena,Calif., control the rover’s movements.The team will analyze its datatransmissions, and while the roversleeps through the night, refine plansfor the next sol’s (a Martian day)activities.

The two NASA rovers — Spirit and Opportunity — will take panoramic images of Mars.The cameras will provide 360-degree views of the terrain. These will allow scientists toselect promising geological targets. Then the rovers will drive to those locations to performscientific investigations during their 90-day mission. Each 380-pound rover could travelas far as 100 yards in one day.

6-footman 4-foot-

9-inchrover

6-footman

Arrivals

Sun

OpportunityJan. 25

SpiritJan. 3

SpiritJuly 10

OpportunityJune 10

Departures

Earthorbit

Marsorbit

The long journey

6D · MONDAY, JANUARY 5, 2004 · USA TODAY

Science

Everybody knows there’s nothing doingEverything is closed it’s like a ruinEveryone you see is half asleepAnd you’re on your own you’re in the streetGood morning, good morning . . .

— The Beatles(Good Morning, Good Morning )

p p p

Tired but ecstatic, scientists began ex-ploring their new playground on MarsSunday by blasting The Beatles in theirCalifornia control room and celebratingnew pictures from the Red Planet.

Their probe, Spirit, was awakened as thescientists played Good Morning, GoodMorning and studied pictures the crafttook as it descended onto the planet Sat-urday night. The images provided the sci-entists with their first glimpse of their

home away from home — an area they willstudy for months.

Scientists are thrilled with what theyhave seen. “Home sweet home,” saysSteve Squyres, lead investigator. “This isour new neighborhood.”

Michael Watkins, one of the navigators,called Spirit’s landing a “bull’s-eye” be-cause the craft entered the atmospherejust 660 feet away from its target in theConnecticut-sized Gusev Crater.

But exactly where the probe ended upon the surface was still part of the scien-tific debate Sunday. Scientists must pin-point the location before sending signals.

They zeroed in by comparing picturesSpirit took just before it landed with im-ages that have been taken over the yearsby other craft orbiting Mars.

“We know with great certainty that weare in the place where we absolutelywanted to be,” Squyres said.

That spot has more to do with accessi-bility to rocks than breathtaking views.

“What we wanted was someplacewhere Mother Nature has cleaned off therocks for us,” Squyres said, showing a pic-ture of the planet’s surface. “Those mar-velous snakelike features are dust-deviltracks. Dust devils (whirlwinds of dust) aregood at swirling dust up off the surface andcleaning up rocks.”

Rocks hold clues to the planet’s past.

And Spirit will study those rocks — attimes using an arm to reach out and touchthem for analysis — to try to answer ques-tions about water and life on Mars.

Squyres chuckled at the thought of be-ing able to reach out and touch a Martianrock within just a few days: “That wouldbe cool.”

He said Spirit’s neighborhood appears“a lot easier to drive on” than that faced bythe Viking and Pathfinder probes. “It’s re-markably devoid of big boulders. That isjust glorious, because big boulders aresomething we have trouble driving over.”

Which way to drive is one of the bigquestions facing the scientific team.

Better pictures will lead the way. Todaythe team expects to begin getting imagesthat are 14 times sharper than Spirit’searly pictures.

“We will have to be a little bit cautious.This is someplace that we’ve never beenbefore, so we are going to tread carefully,”Squyres said.

Asked whether the dust devils pose athreat to Spirit, Squyres chortled. “As faras a dust devil coming in and flipping ourrover over, nuh-uh. Ain’t going to happen,”he said. In fact, the team hopes to spot onewith its sophisticated cameras to make “adust-devil movie.”

“We hit the sweet spot,” he said. “Thereis some great stuff on the horizon.”

For Mars lander scientists,nothing to say but it’s OK Beatles tune setsSpirit groovingacross Red PlanetBy Dan Vergano and Robert DavisUSA TODAY

NASA/JPL via AP

“Home sweet home”: The Mars probe Spirit has begun transmitting pictures from theRed Planet and is expected to begin sending higher-quality shots sometime today.

Q: Where is Spirit right now?A: As intended, Spirit appears close to

the middle of Gusev Crater, a huge bowlthat may have once held a lake. Scientistsdo know it rests upright — a very goodthing — atop its landing craft and the de-flated airbags that cushioned its landing.

Q: What is it doing?A: The priority now is pinpointing the

rover’s position and its exact heading sothat its high-power antenna — a lollipop-shaped object on its top — can be pointedtoward Earth. That antenna will allow sci-entists to communicate directly with Spir-it instead of using an orbiting craft as a go-between, as they were on Sunday. Scien-tists also say solar power is about 20% lessthan expected for Spirit because of thedust on Mars. They may change plans todeal with the shortfall.

Q: How soon will it start drivingaround?

A: It will start moving nine days after

landing at best, NASA scientists say, soJan. 13 would be the soonest for “egress,”in NASA-speak, from the landing craft.When Spirit landed, it was folded up withits instruments turned off, so engineersand scientists are busy testing systemsand limbering up the rover while plottingwhat path it should take on its three-month exploration. By Tuesday the rovershould be up on its wheels. A 29-inch-highrock is on the right side of the landingcraft, blocking one avenue to roll off, butoverall the platform is tilted only about 2degrees, convenient for egress.

Q: Why did the rover land in a bounc-ing airbag instead of setting down withrockets as in the moon landings?

A: Airbags remove the need for stabiliz-ing rockets and electronics that make“soft” rocket landings possible; they wereenvisioned as a way to save weight andmoney for the 1997 Pathfinder mission.But the method has limits — it’s imprecise,and at 400 pounds, Spirit is about the larg-

est probe likely to try airbag landings onMars, says landing expert Paul Withers ofBoston University. NASA’s next lander mis-sions, scheduled for 2007 and 2009, arelarger and will land with rockets.

Q: Why did last month’s Beagle 2landing apparently go badly when thisone went well?

A: Most likely bad luck and fewer re-sources, Withers says. Any number of ac-cidents might have occurred, but Beagle 2lacked the stabilizing rockets Spirit had tocombat winds, and its airbags were notthe heavy-duty ones used by NASA, whichmight have left it vulnerable to damage.

Q: What are scientists looking forwith Spirit?

A: Finding sedimentary rocks in what isbelieved to be a dried lake in Gusev Craterwould be a first step. The rover might haveto enter smaller craters to look for theselayers of rock. A grinder would show cam-eras and other instruments whether Mars’water came from hot springs, a salty sea orsome other source. Volcanic dust mighthave covered any sedimentary rock in thecrater, and scientists hope examination ofthis rock tells them something about thegeologic history of the Red Planet.

Q: Can Spirit find the lost Beagle 2?A: No; if it indeed landed, it would be

too far away, and scientists don’t knowwhere to look. Spirit mission managerMark Adler says it would take “1,000years” for the rover to reach Isidis Planitia,the flat basin where Beagle 2 was sup-posed to have landed.

Q: Does Spirit’s landing mean that theOpportunity rover scheduled to landJan. 24 also will land safely?

A: Not surprisingly, NASA officials arecautious and say Spirit’s landing went farbetter than expected. But new stabilizingrockets and landing camera systems per-formed better than expected, “whichgives everybody very high confidence,”says Louis Friedman, head of the PlanetarySociety, a space exploration advocacygroup whose companion event to theSpirit landing in Pasadena drew a stand-ing-room-only crowd of 2,000.

Q: What are the “Sol” days that scien-tists mention when they say what timeit is on Mars?

A: A Sol is a Martian day: 24 hours, 39minutes, 35 seconds. About 40 membersof the rover science team will be living ona “Sol” schedule, instead of Earth time,during the mission.

Q: Where is Opportunity headed?A: Meridani Planum, a smooth equato-

rial plain marked by deposits of gray he-matite, an iron oxide mineral usually asso-ciated with water on Earth. Once again,NASA is trying to “follow the water” in itsexploration of Mars.

The hows, whys and wheres of the latest Mars exploration

NASA/JPL via AP

Safe landing: Rover as seen on Saturdayby its navigation camera.

NASA has cleared a giant hurdle in landing a rover on Mars. USA TODAY’s Dan Vergano and Robert Davislook at this new chapter in space exploration.

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