MADISON, Wis. -- The latest spaceship to visit Mars has found evidence of another ancient, cataclysmic flood two or three times greater than the deluge discovered last year by the Pathfinder lander.
The flood detected by the Mars Global Surveyor, which has been orbiting the red planet since September 1997, probably contained enough water to fill a basin the size of Utah 100 yards deep, according to Michael Malin, a Mars specialist attending an astronomical conference here. It is additional proof that Mars was once warm and wet, like Earth, and might have harbored primitive life.
After spending a year analyzing data beamed back to Earth by Pathfinder, astronomers are getting their first look at the preliminary findings of the Global Surveyor, the second in a series of at least 10 Mars missions planned over the next decade.
One intriguing discovery is that Viking I, the first spaceship to land on Mars, in 1976, did not come down where scientists thought it did, but about seven miles farther east, a goof that will make it necessary to redraw all the Mars maps.
The discrepancy turned up when the Global Surveyor photographed the supposed Viking site and found that certain nearby features, such as sand dunes and a large boulder nicknamed "Big Joe," were nowhere to be seen.
Pathfinder's site -- about 400 miles away -- is known precisely, and that made it possible to recalculate Viking's location.
An error of seven miles might seem small, but it is important since all the lines of longitude and latitude on Mars were based on the position of Viking, Malin said. Future scientific photographs, robotic and even manned landings depend on accurate positioning.
Pub Date: 10/13/98