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Planetary News: Genesis (2004)Despite Mishap, Genesis Scientists Believe That Mission’s Goals Can Be AccomplishedBy Amir Alexander10 September 2004 Things are looking up for Genesis team scientists today, as a close examination of the sample return capsule revealed that much of the mission’s scientific payload remained intact. “We were rather demoralized by the events of last Wednesday” said recovery team chief engineer Don Sevilla of the Jet Propulsion Laboratory, but things have been looking up since then. “We have the patient in the processing facility” he added, “and we will soon be peeling back the layers of the onion.” The “onion” in question is the damaged Genesis sample return capsule that was supposed to be recovered in mid-air by helicopters on Wednesday, but instead crashed into the Utah desert. By evening, the capsule was dug out of the ground and transported to the U.S. Army base at the Dugway Proving Grounds. The science canister – the scientific heart of the mission - was then removed from the capsule and placed in a clean room. During the rough landing the science canister was ripped open, exposing the Solar wind collector arrays and the concentrator instrument inside. On Thursday, Genesis scientists pushed a small mirror on a stick through the gap in the canister’s envelope and looked around. They were pleasantly surprised: considering the severity of the impact, said Sevilla, “it is amazing how clean it is inside.” While some of the collecting panels were clearly broken, others were not. In particular, scientists were pleased to see that the concentrator instrument and the panel known as the “gold foil” appeared fully intact. As for the particles that are embedded in collector panels that were shattered in the landing, they are not lost to science either. Each panel, explained Wiens, is of a different thickness, and can therefore be pieced together from all its separate shards. The panels, he added, were deliberately designed this way, in preparation for just such a contingency. For most samples, it makes no difference whether they are embedded in broken shards or whole panels. The main challenge confronting Genesis scientists is dealing with the contamination of the samples, the inevitable result from the breach of the science canister. According to the original plan the canister was to be rushed by helicopter directly to the clean room at a nearby Air Force base, where it would be immediately treated to remove all traces of Earthly contamination. Not only was this stringent timetable made impossible by the crash, but the collector plates were sprinkled liberally with Earth and air that entered through the breach in the canister’s shell. Before scientists can properly investigate the samples, they must carefully separate the wheat of the samples returned by Genesis from the chaff of contamination. Otherwise they will never be sure whether their studies are base on the properties of pristine particles from the Sun or on the characteristics of dirt from the Utah desert. The members of the Genesis science team believe this can be done. Most of the contamination, explained Wiens, will be found on the surface of the collector panels. The actual Solar wind particles will generally be embedded deeper, because the hit the panels at a much higher speed. In some cases, however, this will not be the case, and other methods will have to be used to remove the contamination. “Give us time, and we will show you what we can do” said Genesis Principal Investigator Don Burnett of the California Institute of Technology. “We will just have to work much harder than we wanted to.” “We are confident that that we can achieve a high degree of success with our science goals” added Wiens. Genesis was launched on August 8, 2001, on an ambitious mission to capture particles of the solar wind and bring them back to Earth. For that purpose it was stationed at a point in space known as “Lagrange 1” or simply "L1" – just inside the Earth’s orbit, where the gravitational pulls of the Sun and the Earth ae at an equilibrium. There, outside the shelter of the Earth’s magnetic field and atmosphere, it was subject to the full force of the particle stream emanating from the Sun. With its three collector arrays spread open, it gathered a miniscule samples of charged particles that make up the solar wind. Scientists believed that these particles had remained unchanged for billions of years, and have much to teach us about the origins of the Solar System. A capsule containing the samples collected by Genesis three years was due to parachute to Earth on the morning of September 10, 2004. Helicopters with professional stunt pilots at the helm were already hovering in their assigned position, waiting to snag the capsule in mid-air as it parachuted gently to Earth. For reasons as yet unknown, the parachutes did not unfurl and the capsule slammed into the ground at close to 200 miles per hour. A special NASA panel is now investigating the accident and will report its conclusions in a few months.
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