The weekend brought good news for NASA scientists. Saturday evening the Opportunity rover landed safely on Mars in a shallow crater on the opposite side of the planet from its injured twin, Spirit. About four hours later the spacecraft began sending much-anticipated pictures back to Earth.

"Opportunity has touched down in a bizarre, alien landscape," observes principal investigator Steve Squyres of Cornell University. "I'm flabbergasted. I'm astonished. I'm blown away." The pictures reveal a landing site darker than any previously visited by a spacecraft on Mars, and some exposed bedrock--the first ever seen on the Red Planet. (The image shown here is the first color picture from Opportunity.)

Opportunity will spend the next 10 days or so preparing to drive off the lander. After that, the rover will study the soil in its immediate surroundings, and then make its way over to the bedrock outcrop, which it will examine in great detail. The Meridiani Planum region to which Opportunity was sent contains vast deposits of crystalline hematite, a mineral that usually forms in the presence of water. The small crater in which the spacecraft landed appears to have exposures of both the hematite unit and the underlying layer of light-colored rock. Analysis of these deposits by the rover may allow scientists to determine whether the hematite formed in a lake or perhaps in a volcanic environment, as some researchers have theorized.

NASA investigators were further encouraged by the progress made in understanding what ails the Spirit rover, which has been malfunctioning since Wednesday. The agency reported on Sunday that the glitch is probably related to the software that controls the rover's flash memory. Says project manager Peter Theisinger, "I think we've got a patient that's well on the way to recovery."

Meanwhile, repeated attempts over the past few days to contact the Beagle 2 lander, part of the European Space Agency's Mars Express Mission, have failed. "We have to begin to accept that, if Beagle 2 is on the Martian surface, it is not active," lead Beagle 2 scientist Colin Pillinger said at a press briefing in London yesterday afternoon. "That isn't to say that we are going to give up on Beagle. There is one more thing that we can do--however, it is very much a last resort. We will be asking the American Odyssey spacecraft [team] tomorrow whether they will send an embedded command--a hail to Beagle with a command inside it. If it gets through, it will tell Beagle to switch off and reload the software. We are now working on the basis that there is a corrupt system and the only way we might resurrect is to send that command."