Found and lost.

Ever since NASA lost contact with the Mars Polar Lander in late 1999, minutes before it was to have parachuted onto the Red Planet, astronomers have been looking for the craft's remains. Last summer, astronomers reported that a camera aboard the orbiting Mars Global Surveyor had found what seemed to be the lander's debris (SN: 6/4/05, p. 366). But the researchers now say that they were wrong.

Michael C. Malin of Malin Space Science Systems in San Diego and his colleagues based their original findings on images taken in January 2000 by Surveyor's high-resolution camera. A dark streak appeared to be evidence of a rocket having blasted the Martian soil, while bright spots appeared to be remains of the parachute and body of the lander.

However, follow-up images taken by Surveyor last September tell a different story. In the new images, the dark streak has faded. Although the fading might simply have been due to dust deposited from one of Mars' frequent storms, other evidence is more damning, the team notes.

The new images show no sign of the bright spot that the team had identified as the lander in the earlier images. Moreover, closer inspection of the old images shows several blurry dark and bright spots that don't appear in the new pictures. The spots that had seemed to indicate lander debris were just electronic noise, the researchers announced Oct. 17 on their Web site (http://www.msss.com/marsimages/moc/2005/10/17/).

The task of hunting for the doomed lander will now fall to an ultrasharp camera aboard the Mars Reconnaissance Orbiter, scheduled to arrive at Mars in March 2006.