Mars or bust!

"You've got 70 investigators here who are like kids in a candy store. They're at the end of a fire hose of data."
Mission Scientist Matthew Golombek

Earthlings once again turned their eyes toward Mars in 1997, as two unmanned spacecraft dropped in on our planetary neighbor.

On the Fourth of July, Mars Pathfinder -- protected by large air bags -- crash-landed in the Ares Vallis area of Mars and almost immediately sent back dazzling images from the planet's surface.

Stowed aboard was Sojourner, which came to be dubbed by its NASA handlers as "the little rover that could." The rover -- humanity's first autonomous vehicle to travel on another planet -- got up close, sending back chemical analyses of soil and rocks.

Across the world, Pathfinder's arrival was heralded with more fanfare than any space event since, perhaps, Apollo 11 landed on the moon. Giddy scientists gave the rocks nicknames such as Barnacle Bill and Yogi. NASA's Pathfinder Web sites broke all known records on the Internet.

Pathfinder's mission was planned to last 30 days, and Sojourner was only expected to run for a week. But the batteries held out, and the mission continued for three months, sending back 2.6 billion bits of information and 16,000 images.

The last word from Pathfinder came on October 7, and an effort to hail the spacecraft on November 1 went unanswered.

While one team of NASA scientists watched the data stream in from Pathfinder, another monitored Mars Global Surveyor. The Surveyor orbiter arrived at the red planet in September. Its first mission -- to circle Mars for about two Earth years, mapping the planet's entire surface.

Surveyor slowed itself with a new procedure called aerobraking -- flying through the upper layers of the thin Martian atmosphere. The probe is already sending back images, but problems with aerobraking led to a one-year delay in the mapping, now set to begin in March 1999.

The maps from Surveyor will help find landing sites for future missions, planned for 1998, 2001, 2003 and 2005. Once its mapping mission is completed, Surveyor is to continue orbiting Mars as a communications satellite for another three years.