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![]() Scientists optimistic about salvaging Genesis mission BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: September 10, 2004 Two days after a spacecraft carrying samples of the solar wind crashed into the Utah desert, scientists are increasingly optimistic about accomplishing most, if not all, of the mission's primary science objectives.
The $264 million Genesis mission was launched in 2001 to capture samples of the solar wind, made up of electrons, protons and trace amounts of various atomic nuclei blown away from the sun's outer atmosphere. By determining the actual concentrations of various atomic particles in the tenuous wind, scientists hope to refine current theories about the composition of the original cloud of gas and dust that coalesced to form the solar system and to gain insights into how the sun and its retinue of planets evolved. Genesis was equipped with five solar wind sample collector panels made up of materials selected because of their suitability to capture specific types of atomic particles. A primary objective of the mission was to collect different isotopes of oxygen in a so-called "concentrator." To protect the fragile collectors from breaking, the Genesis sample return canister was designed to descend under a large parafoil before being plucked out of the sky by a helicopter. Genesis spent 27 months collecting solar wind samples in deep space before heading back to Earth last April. The sample canister re-entered Earth's atmosphere Wednesday, but its braking parachutes never deployed and the canister hit the ground at some 193 mph, burying itself halfway in the desert soil. The return vehicle's inner sample canister ruptured on impact. Fearing the worst, engineers peeking inside the canister, using flashlights and mirrors, were amazed at what they found. "We were rather demoralized by the events of last Wednesday," said Don Sevilla, the lead payload recovery engineer at the Jet Propulsion Laboratory in Pasadena, Calif. "But we have our patient in our processing facility and we are being meticulous in our investigation of it before we start peeling back the layers of the onion. "I can tell you that yesterday morning, we had great cause for optimism in that exploring into the canister with flashlight and a small mirror on a stick, we were able to find one of our primary science materials, which is the concentrator target, and it appears intact. "There is also another target material, called gold foil, that we have determined to be in very good condition and so we have great cause for some sense of recovery here, that things are looking much better today than they felt on Wednesday. Said Wiens: "The science team is really excited about having these materials intact, or mostly intact. With these samples brought back from space, we should be able to meet many, if not all of our primary science goals. "The concentrator was designed to help us achieve our number one science objective, and that is measuring the oxygen isotope composition of the sun, which will help us understand some of the details about how our solar system was formed. These samples appear to be intact. Our second, third and fourth goals should also be met as we have samples to address these issues as well. A major concern, however, is contamination from particles in Earth's atmosphere. No attempts will be made to study fragments of solar wind collector material until extensive tests have been conducted to determine the most effective techniques for removing contamination. "It's actually quite amazing for the amount of breach of our canister, how visibly clean it is inside," Sevilla said. "The SRC, the sample return canister, has been broken up pretty badly and there's a fair amount of dirt. But the very contamination-sensitive materials inside the canister, we're not talking about great clods of dirt. There is still polished metal, looking very pretty inside our rather ugly patient." In the near term, the smashed-up sample return canister will remain at the Utah Test and Training Range until engineers determine how best to transfer it to an ultra-clean facility at the Johnson Space Center in Houston. "We're working by the scientific method and preserving this precious material," Sevilla said. "You can be sure the collector materials we have are not going to be touched until we know how to keep them safe. ... This is something that's going to take months." Two independent investigations teams are being formed to look into the Genesis re-entry failure. It's not yet known what went wrong Wednesday, but preliminary examination of the remains of the sample canister show the parachute system never received commands to fire. Officials would not speculate on what components could have contributed to the accident and they did not mention a critical battery in the canister that ran too hot early in the mission because of a radiator problem. "All we know today is that the message (to deploy the initial parachute) apparently did not arrive at the devices that were supposed to deploy the chute," said Gentry Lee, a senior engineer at JPL's planetary systems division. "Any identification of any root cause beyond that at this stage would be speculation and there are people who will be investigating this in great detail in the near future." Also studying the Genesis failure will be engineers with NASA's Stardust mission, which will return to Earth in January 2006 carrying samples of a comet. The Stardust sample canister is scheduled to make a parachute descent to the same Utah test facility, hitting the ground at about 10 mph. No helicopters are required, but its parachutes are. "The Stardust mission is already starting an examination of the lessons learned from Genesis," Lee said. "This will be a long process and there will be some things that can be done and some things that can't. It is, after all, flying and there's nothing that can be done about the overall design. It will be a question of how to maximize the probability of success given what has been learned from Genesis." |
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