Published: June 30, 1997

Hubble Space Telescope images taken June 27 by a team of scientists that includes two Colorado researchers indicate a large dust storm on the Martian surface may be moving toward the July 4 landing site of NASAÂ’s unmanned Pathfinder spacecraft.

The researchers took high-resolution color images of the side of Mars where the landing site is located in the early morning, mid-morning and early afternoon of June 27 to check out the weather conditions prior to the Pathfinder landing. The imaging team includes Steve Lee of the University of Colorado at BoulderÂ’s Laboratory for Atmospheric and Space Physics, Todd Clancy of BoulderÂ’s Space Science Institute, Phillip James of the University of Toledo, Mike Wolff of the Space Science Institute and Jim Bell of Cornell University.

The dust storm is filling the Valles Marineris canyon system -- a series of five- to eight-kilometer deep canyons stretching over the Martian surface area for 3,000 kilometers, or about 1,800 miles, said Lee. Reaching within about 600 miles of the Pathfinder landing site known as Ares Valles, the dust storm may be moving north, filling in the canyons and other surface depressions on the planetÂ’s surface.

“This is something we did not expect to see -- it’s very early in the Martian year for major dust storms to occur,” he said of the event. “It could go away tomorrow, stay for weeks or turn into a global dust storm. We haven’t seen a storm like this one before, so we just don’t know.”

Unless the dust storm evolves into a massive, global event, its effects on the Pathfinder mission should be minimal, said Lee.

HST and microwave observations taken by the team in March, April and May indicated the planet was cold and cloudy, said Lee. Those climate conditions are in stark contrast to the relatively warm and dusty conditions that existed when NASAÂ’s unmanned Viking and Mariner 9 spacecraft visited Mars in the 1970s.

The images are expected to be released over the Internet by the Space Telescope Science Institute in Baltimore prior to the PathfinderÂ’s landing, said Lee. The team will continue to monitor Mars with HST for several months following the landing.

Pathfinder, which consists of a stationary lander and a tricycle-sized surface rover, will descend on the planet with the aid of parachutes, rockets and airbags. Both the lander and rover will carry a variety of scientific equipment and cameras and beam images back to Earth beginning July 4.

The lander will touch down in an ancient floodplain known as Ares Vallis, some 500 miles southeast of where the Viking 1 spacecraft landed in 1976.

Six ¶¶ÒõÂÃÐÐÉä-Boulder alumni are working for NASAÂ’s Jet Propulsion Laboratory on the Pathfinder mission, including mission manager Richard Cook, navigation team leader Pieter Kallemeyn, flight engineers Guy Beutelschies and Albert Nakata, imaging team member Justin Maki and postdoctoral researcher Nathan Bridges.