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Planetary News: Genesis (2004)Genesis - Stunt Pilots to Retrieve "A Piece of the Sun" for NASABy Amir Alexander19 August 2004 It is a feat to challenge the skills of the best helicopter pilots in the world: Hover at an altitude of 10,000 feet for 10 minutes, waiting for a refrigerator-size object to parachute out of the sky. Then, swoop down 8 feet over the parafoil with an 18.5 foot pole extended below the aircraft, and grab the parachute with its 420-pound payload in mid flight. Finally, with the apparatus dangling from the helicopter at the end of a 450 foot cable, descend slowly and deposit it gently upon the ground. Few helicopter pilots are up to this task, and when Roy Haggard of Vertigo, Inc. went looking for "a few good men" to perform it, there were no takers. “Most helicopter pilots are agoraphobic,” said Haggard, “they spend most of their time between the ground and 500 feet.” When he told them the mission required waiting at twenty times that height and then executing a controlled collision with another aircraft in midair, bringing it down to the ground, the response was always the same: “no, we don’t want to do that…” Haggard, however, could not give up. Working under contract for NASA, it was his job to find the people who could retrieve the reentry capsule of the Genesis mission by grabbing it in mid-air. Faced with the reluctance of most civilian helicopter pilots to take on the job, he expanded his search: “at every avenue we explored,” he said, “we were referred back to stunt pilots,” those who spend much of their time carrying cameras and chasing down cars at low altitude on Hollywood movie sets. He found two of the best: Dan Rudert of Santa Ana, California, and Cliff Fleming, a former Marine who is currently doing the flying on the set of Batman 4. “Between us,” said Rudert, “we have 50 years of experience and over 20,000 flight hours.” These were precisely the skills and experience Haggard was looking for, and he quickly signed them on. In practice, they have had a 100% success rate, hooking a dummy capsule by its parachute 11 times in 11 attempts. The real test will come September 8, when the Genesis sample return capsule will reenter Earth’s atmosphere and parachute down to the Utah desert. 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 are 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 sample of charged particles that make up the solar wind.
In April of this year Genesis stored away its collecting arrays and headed back to Earth. On September 8, with the help of Rudert and Fleming, it will finally come home. This will be the first time since the end of the Apollo missions that samples collected in space will be returned to Earth, and scientists around the world are eagerly awaiting their arrival. They hope that true to its name, Genesis will provide clues on the origins and history of the Solar System. Our Solar System, explained Genesis Principal Investigator Don Burnett of the California Institute of Technology, was formed out of a cloud of whirling cosmic dust billions of years ago. Over time the cloud collapsed into a spinning dust disk, or nebula, which over a few tens of millions of years thinned out to form the Sun and planets we know today. But while scientists understand the broad outlines of this process, there is much that they still don’t know. In general, scientists are eager to learn more about how such widely different environments, ranging from the rocky and watery Earth to the gaseous giant planets, all developed from the same cloud of gas and dust. Scientists know, for example, that the distribution of different elements and their isotopes differ in various parts of the solar system, but they are not sure how this came about. How then did we get from the homogeneous primordial nebula to the highly differentiated Solar System we know today? The best way to learn about this process, Burnett and his colleagues reason, would be to compare the composition of the primordial cloud with objects in the “modern” Solar System. Unfortunately, the cloud is not exactly available for study since it dissipated billions of years ago. There is, however, one exception: the extreme outer layer of the Sun, its atmosphere, has remained practically unchanged since the formation of the Solar System. When particles from this layer stream out into space in the form of solar wind, they serve as emissaries from billions of years ago, when all that filled this region of our galaxy was a swirling mass of gas and dust. It was Genesis’s mission to capture these ancient Solar particles and bring them back to Earth. It didn’t capture much: when compared to the massive Moon rocks brought back by the Apollo astronauts, the size of the sample returned by Genesis is miniscule. It will, however, be all that scientists need. “Our spacecraft has logged almost 27 months far beyond the Moon’s orbit collecting atoms from the Sun,” said Burnett. “With it, we should be able to say what the Sun is composed of at a level of precision that has never been seen before.” When Rudert and Fleming deposit the return capsule safely on the ground, their job will not be over. Along with support crews, they will detach the parafoil, and attach the capsule more securely to the helicopter. They will then fly it to a specially prepared clean room at Michael Army Air Field. Within a week it will be at NASA’s Johnson Space Center in Houston, where samples will be prepared for study by scientists around the world. Genesis, the first mission ever to return samples from beyond the Moon’s orbit will then be at an end, but the study of the samples it collected will only begin. |
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