About 242 million miles away, on the far side of the sun, NASA’s armored Stardust spacecraft survived an unprecedented flight Friday through the gas and dust plumage of a comet, grabbing up pieces of the debris as they pelted it at six times the speed of an assault rifle bullet. The mission was the first designed to collect and bring back samples from any body in space since humans traveled to the moon, and the first ever to dive through the vaporous but dangerous gas and dust cloud of one of the most primitive bodies in the solar system to retrieve samples.
At 2:22 p.m., Jan 1, at a closing rate of 14,000 mph, the tiny robotic probe passed within 143 miles of the four-mile-wide nucleus of Comet Wild 2 (pronounced Vilt 2), which is believed to contain clues to the formation of the planets and the origins of life. Many scientists suspect comets played a major role in seeding Earth and other worlds with the building blocks of life and in delivering the water that fills the planet’s oceans.
“Good news. . . . We’ve passed the closest approach point without any injury, apparently,” comet scientist Donald Yeomans of the Jet Propulsion Laboratory here said shortly after the event, which triggered cheers, claps and handshakes in the control room. JPL manages the mission for NASA.
He noted later that an astronaut in a spacesuit, subjected to such a furious sandblasting, would have been reduced to “particles as fine as the [comet] dust.” At a news briefing later, members of the Stardust team beamed as they showed off the first of a number of images expected from the encounter. The photo, which the scientists called surprising, revealed the comet nucleus to be a rounded snowball with deep pits, one of them big enough to contain 40 or 50 Rose Bowls, Duxbury said.
The picture also revealed five jets coming out of the comet’s surface, including a couple of larger ones. The photo will for the first time allow scientists to relate such jets, which had been previously observed in less detail, to the surface features from which they emanate. Several scientists said they were glad they did not know about the jets “gunning” for Stardust earlier, because as it turned out, the craft sailed through them.
Don Brownlee of the University of Washington, lead Stardust scientist, compared the encounter to Russian roulette. “We were really worried about the impact of things larger than a grape or a marble,” which could have damaged the propellant tank or other vital components. The scientists expect to get more and better images taken closer to the comet nucleus over the next day or so. The comet cooperated to provide “fantastically exciting” images, Brownlee said. “These pictures are going to open up a new door on our understanding of how comets work.”
The craft’s next assignment is to deliver the treasure, sealed in a reentry pod, by parachute to an Air Force test range in the Utah desert, in January 2006.
The scientific returns from the mission are “going to tell us about the early formation of our solar system, the role that comets have played in the formation of Earth and ourselves, that will unfold over the next few years,” Duxbury said. “The science that this project is returning will be unprecedented.”
By Kathy Sawyer
Washington Post Staff Writer.
