Launch Opens New Era of Mars Study

TIMES SCIENCE WRITER

A new era of Mars exploration began Friday when a Titan III rocket lofted the Mars Observer into space in the first of a planned series of ambitious missions by the United States, Russia and Europe over the next decade.

The booster lifted off at 10:05 a.m. PDT, about 30 minutes behind schedule, into the hazy skies above Cape Canaveral Air Force Station in Florida. An anxious 84 minutes followed as a new type of upper stage rocket that was to hurl the Observer toward Mars failed to signal that the craft had received an extra jolt needed to free it from Earth's gravity.

Finally, a tracking station in Canberra, Australia, confirmed that the craft was in the right place at the right speed at the right time for its 11-month journey through space. "We have a healthy spacecraft, on target and on its way to Mars," flight commentator George Diller announced as control room technicians exchanged thumbs-up signs, shook hands and embraced.

At the Jet Propulsion Laboratory in Pasadena the news was greeted by cheers in a computer-filled office where scientists formally took over the operation of the Observer, the first U.S. spacecraft sent to Mars since the Viking missions launched in 1975.

Other questions developed about the condition of some instruments aboard Observer, including a critical antenna. Observer managers expected the main antenna to trip a sensor as it unfolded to a position from which it could transmit information. But they received no signal at first, making them wonder if they faced a problem that JPL project manager Dave Evans termed "familiar," wincing as he spoke. The main antenna on JPL's Galileo spacecraft, which is Jupiter-bound, is partly stuck and cannot send data.

JPL spokesman Franklin O'Donnell speculated at the time that the antenna had emerged but that the sensor was not working. If the antenna had not deployed, he said, it would have shielded other components inside Observer and temperatures would have been rising. That was not the case.

At 4:32 p.m., the mission team finally received a signal from the sensor and determined that the antenna was deployed properly. They said the deployment apparently had taken longer than expected.

"We expect all of the kinks . . . to be worked out," said NASA project scientist William Piotrowski at a post-launch briefing. "We expect to arrive at Mars next August with a fully functioning spacecraft."

Attention is turning back to the fourth planet from the sun after a period focusing on Venus, largely because of the Bush Administration's goal of landing astronauts on Mars by the year 2019.

Before then, Mars is expected to get visits from orbiters like the Observer, from balloons that will sail through the planet's pink skies and from robots that will traverse the rocky red hills, ancient flood channels and polar tundras. Soil samples may be returned to Earth for study.

Many countries, including France, Russia, Japan and the United States, are cooperating on Mars projects. The Observer, for example, is carrying a French-built transmitter that will relay data from Russian balloons scheduled for release on Mars in 1995.

Taken together, the various experiments are designed to solve some big mysteries left over from the Mars investigations of the 1970s. Does life exist there, and if it doesn't, did it once? What happened to the water? Can human beings live there for any length of time?

Scientists say the information they gather can help them better understand the environment of Earth as well as Mars and pave the way for people on the Red Planet.

The Mars Observer project, which will cost $900 million to $1 billion, is designed to take the first step, providing a daily weather map of Mars much like the satellite photos shown on television newscasts, and a global map. A camera should be able to capture images of objects as small as a car in areas of great interest, including the Cydonia region. Some think they see pyramids and sculpture in the region, but most planetary scientists think they see unusual rock formations. Mapping is scheduled to begin in the fall of 1993.

The Observer is designed to circle above the poles every 118 minutes for 687 Earth days, a full Martian year, so that geological and atmospheric information will be available for all four seasons. Its instruments will scan the planet from 250 miles above the surface.

The surveys should help determine where to scout for water--conventional wisdom is that some is still frozen beneath the surface--and for minerals that can be broken down to provide oxygen or piled up to build structures for human colonies.

Observer researchers also want to analyze the polar regions for evidence of climate changes as dramatic as the Ice Ages and warm epochs on Earth. "We will examine the layers in the permanent portions" of the ice caps, said Ken E. Herkenhoff, a participating scientist.

Evidence of an Earth-like past would lead scientists on an intensive quest for clues to what led to the planet's transformation and for fossils of life forms.

But first the Observer must travel 450 million miles, arriving intact and functioning.

Already, there have been hitches, some of them echoes of previous NASA failures.

The Observer's original 1990 launch date was delayed in one of a flurry of postponements after the space shuttle Challenger exploded, killing its crew. More recently, a launch planned for Sept. 16 was canceled because a technician accidentally contaminated the craft with debris-laden nitrogen gas. The capsule and the delicate instruments aboard had to be resterilized.

Several months ago, payload manager Gary Reisdorf said he discovered that one of the Mars-bound cameras was out of focus. He spent $1 million and worked 12 hours a day for seven weeks to fix it.

The launch also was a test of a new upper stage vehicle, the transfer orbit stage, that fired after separation from the Titan rocket. The TOS, as it is known, was to accelerate to more than 25,400 m.p.h., the speed needed to free the Observer from Earth's gravity.

The worst fears of scientists were embodied in a joke that had been making the rounds in the days immediately preceding the launch. Reisdorf repeated it: "The good news is the TOS has been achieved. The bad news is, we're on the way to Venus."

When the announcement came that the craft was speeding toward Mars, Reisdorf sighed audibly and turned to a cluster of colleagues. "Champagne?" he asked.

America's Return to Mars

Mars Observer is the first U.S. probe bound for the red planet since Viking 1 and 2, launched in 1975.

Spacecraft is to assume a 250-mile-high polar orbit, taking measurements of the Martian surface and atmosphere. The Observer may also be used to relay signals from Russian Mars probes schedules for 1994 and 1996.

Planets compared: Mars: Diameter in miles: 4,222 Moons: 2 Rotation: 24 hr. 37 min. Year in Earth days: 687

Earth: Diameter in miles: 7,926 Moons: 1 Rotation: 24 hr. Year in Earth days: 365 Source: NASA, Jet Propulsion Laboratory

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