The Genesis Mission :
Genesis was a NASA probe that collected a sample of solar wind particles and returned them to Earth for analysis. It was the first NASA sample-return mission to return material since the Apollo program, and the first to return material from beyond the orbit of the Moon. Genesis was launched on August 8, 2001, and the sample return capsule crash-landed in Utah on September 8, 2004, after a design flaw prevented the deployment of its drogue parachute. The crash contaminated many of the sample collectors. Although most were damaged, some of the collectors were successfully recovered.
The sample return capsule entered Earth's atmosphere over northern Oregon at 16:55 UTC September 8, 2004, with a velocity of approximately 11.04 km/s (24,706 mph). Due to a design flaw in a deceleration sensor, parachute deployment was never triggered, and the spacecraft's descent was slowed only by its own air resistance. The planned mid-air retrieval could not be carried out, and the capsule crashed into the desert floor of the Dugway Proving Ground in Tooele County, Utah, at about 86 meters per second (311 km/h (193 mph)).
The capsule broke open on impact, and part of the inner sample capsule was also breached. The damage was less severe than might have been expected given its velocity; it was to some extent cushioned by falling into fairly soft ground.
The root cause of the failed deployment of the parachutes was announced in an October 14 press release. Lockheed Martin had built the system with an acceleration sensor's internal mechanisms wrongly oriented (a G-switch was installed backwards), and design reviews had not caught the mistake. The intended design was to make an electrical contact inside the sensor at 3 g (29 m/s²), maintaining it through the maximum expected 30 g (290 m/s²), and breaking the contact again at 3 g to start the parachute release sequence. Instead, no contact was ever made. It was installed backwards.
The mission's primary science objectives were to obtain precise solar isotopic abundances of ions in the solar wind, as essentially no data having a precision sufficient for solving planetary science problems are available; To obtain greatly improved solar elemental abundances by factor of 3-10 in accuracy over what is in the literature; To provide a reservoir of solar matter for 21st century science to be archived similarly as the lunar samples.
Note that the mission's science objectives refer to the composition of the Sun, not that of the solar wind. Scientists desire a sample of the Sun because evidence suggests that the outer layer of the Sun preserves the composition of the early solar nebula. Therefore, knowing the elemental and isotopic composition of the outer layer of the Sun is effectively the same as knowing the elemental and isotopic composition of the solar nebula. The data can be used to model how planets and other Solar System objects formed, and then extend those results to understanding stellar evolution and the formation of planetary systems elsewhere in the universe. Clearly, the ideal sample collection option would be to send a spacecraft to the Sun itself and collect some solar plasma; however, that is difficult because of the intense heat of the Sun's superheated gases, as well as the dynamic electromagnetic environment of the solar corona, whose flares regularly interfere with the electronics of distant spacecraft. Fortunately, the Sun continuously sheds some of its outer layer in the form of solar wind. Accordingly, in order to meet the mission science objectives, the Genesis spacecraft was designed to collect solar wind ions and return them to Earth for analysis. Genesis carried several different solar wind collectors, all of which passively collected solar wind; that is, the collectors sat in space facing the Sun, while the ions in the solar wind crashed into them at speeds over 200 km/s and, on impact, buried themselves in the surface of the collectors. This passive collection is a process similar to that used by the semi-conductor industry to make certain types of devices, and a simulation of the process is given by the free-access program SRIM.
Most of the Genesis collectors continuously sampled all of the solar wind which the spacecraft encountered (the "bulk solar wind"). However, the spacecraft also carried three arrays of collectors which were deployed when specific "regimes" (fast, slow, coronal mass ejections) of solar wind were encountered, as determined by the electron and ion monitors on board.
These deployable collector arrays were designed to provide data to test the hypothesis that the rock-forming elements keep their relative proportions throughout the processes which form the solar wind.
There was a third type of collector on Genesis: the concentrator, which collected bulk solar wind, but was discriminating in that it electrostatically repelled hydrogen and had enough voltage to focus the lighter solar wind elements onto a small target, concentrating those ions by a factor of ~20. The objective of the concentrator was to bring back a sample with enhanced amounts of solar wind ions to make it possible for analysts to precisely measure the isotopes of the light element.
Genesis was a Discovery-class mission of the NASA Jet Propulsion Laboratory (JPL) at the California Institute of Technology. The spacecraft was designed and built by Lockheed Martin Space Systems at a total mission cost of US$264 million.
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References:
Dugway Proving Ground
https://en.wikipedia.org/wiki/Dugway_Proving_Ground
JPL (Jet Propulsion Laboratory) https://en.wikipedia.org/wiki/Jet_Propulsion_Laboratory
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The Drogue Parachute https://en.wikipedia.org/wiki/Drogue_parachute
https://en.wikipedia.org/wiki/Genesis_(spacecraft)
Accelerometer https://en.wikipedia.org/wiki/Accelerometer
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