Mars' newest resident awoke to its first Red Planet dawn on Sunday, as NASA scientists back on Earth pored over scores of photos the Spirit rover sent back shortly after landing.
The craft landed Saturday night -- mid-afternoon Mars time -- almost exactly on target, at Gusev Crater, a massive basin the size of Connecticut that scientists believe may be the site of dry lake bed once fed by a long, deep martian river. Besides being an ideal place to search for evidence of water, and possibly life, the landing zone is an area free of large boulders and thick accumulations of dust, making it easier to maneuver the rover.
Scientists were jubilant over the success on a planet where two of every three lander missions have produced nothing but space junk.
“It’s a big step forward for all humanity. Now we have another rover on another planet, exploring a new world. What more could you ask?” said Charles Elachi, director of the National Aeronautics and Space Administration’s Jet Propulsion Laboratory.
Rover gets a wake-up call
The first set of black-and-white photos were snapped by Spirit before darkness fell on the frigid martian surface and were relayed to Earth by the passing Odyssey orbiter. They show a flat, wind-scoured plain peppered with small rocks.
“Home, sweet home,” said Steve Squyres, the mission’s main scientist. “This is our new neighborhood ... We hit the sweet spot.”
Spirit settled into a “sleep” mode with the martian sunset, but sprang to life briefly overnight to transmit additional pictures and other data during two more satellite passes, one by the Mars Global Surveyor and another by Odyssey.
At about 2:42 p.m. PT (5:42 p.m. EST), a short time after sunrise on Mars, lab managers reactivated the rover, playing the Beatles song “Good Morning, Good Morning” in the control room to mark the occasion.
Scientist said their principal task during Spirit’s first full day on Mars will be to extend the craft’s main antenna and point it toward Earth to establish a direct communications link with the robotic probe.
They also expect the rover to begin taking higher-resolution color photos that could be sent to Earth early Monday, providing panoramas of the martian surface in unprecedented detail and depth of field.
For now, the six-wheeled rover will remain folded up on its landing pad while mission controllers continue to run checks on its various systems and instruments. In the next day or two, the Jet Propulsion Laboratory team will lift the rover up off its belly and extend its front wheels, mission manager Jennifer Trosper said.
Scientists said it would be eight or nine days before the rover is ready to roll off on its three-month mobile mission.
One early concern abated as closer examination of what had initially appeared to be a large rock standing in the rover’s path revealed the object was probably just part of a partially inflated air bag from the craft’s landing.
'Great place to drive'
NASA targeted Spirit to land within a cigar-shaped ellipse just south of the Martian equator. Based on three grainy photographs taken by the spacecraft as it plummeted to the surface, navigators believed they delivered Spirit to within six miles of its intended target. Brian Portock, of the mission’s navigation team, compared the feat to teeing off from Los Angeles and making a birdie in New York.
Video: Landmarks on Mars Over the next three months, the robot should use a suite of instruments to look for geologic evidence of past water activity in the rocks and soil. If water once filled Gusev Crater, it may have been a place suitable for life.
The terrain surrounding Spirit appeared scattered with small rocks, none larger than about a foot high, Squyres said. The trio of descent images showed the tracks of dust devils thought to frequently scour the area, sweeping it of the rusty grit that coats the planet.
Small pits — sand traps, really — filled with fine-grained material could be made out in the near distance. Rocks appeared abundant, but small enough to allow Spirit to roam unimpeded.
“It’s a great place to drive,” Squyres said.
Just west of the rover, scientists believed they could make out a craterlike depression rimmed by a small mesa that appeared to show ancient rock. Previous Mars missions never have investigated such a feature.
Squyres called it a “tantalizing” feature to explore, but first it must be determined whether it can be done safely. The depression might be full of soft dust that could mire the craft.
“I don’t know for sure it’s not a rover trap,” he said.
It was a little warmer than expected — about 98 below zero Fahrenheit — possibly from heat-trapping dust in the atmosphere.
That meant the solar arrays were generating only 83 percent of the power expected, said Jennifer Trosper, Spirit’s mission manager for surface operations. That could force mission managers to conserve power.
The Associated Press and Reuters contributed to this report.