Genesis Solar Wind Sample Return Mission

The primary mission of NASA's Genesis spacecraft was to collect samples of solar wind particles and return these samples of extraterrestrial material safely to Earth for detailed analysis. The mission's specific science objectives were to obtain precise solar isotopic and elemental abundances and to provide a reservoir of solar matter for future investigation. A detailed study of captured solar wind materials would allow scientists to test various theories of solar-system formation. Access to these materials would also help them resolve lingering issues about the evolution of the solar system and the composition of the ancient solar nebula.

The mission started on August 8, 2001, when an expendable Delta II rocket successfully launched the 1,400-pound (636-kg) Genesis spacecraft from Cape Canaveral Air Force Station, Florida. Following launch, the cruise phase of the mission lasted slightly more than three months. During this period, the spacecraft traveled 932,000 miles (1.5 million km) from Earth to the Lagrange libration point 1 (L1). The Genesis spacecraft entered a halo orbit around L1 on November 16, 2001. On arrival, the spacecraft's large thrusters fired, putting Genesis into a looping, elliptical orbit around the Lagrangian point. The Genesis spacecraft then completed five orbits around L1; nearly 80 percent of the mission's total time was spent collecting particles from the Sun.

On December 3, 2001, Genesis opened its collector arrays and began to accept particles of solar wind. A total of 850 days were logged, exposing the special collector arrays to the solar wind. These collector arrays are circular trays composed of palm-sized hexagonal tiles made of various high-quality materials, such as silicon, gold, sapphire, and diamondlike carbon. After the sample return capsule opened, the lid of the science canister opened as well, exposing a collector for the bulk solar wind. As long as the science canister's lid was opened, this bulk collector array was exposed to different types of solar wind that flowed past the spacecraft.

The other dedicated science instrument of the Genesis spacecraft was the solar wind collector. As its name implies, this instrument would concentrate the solar wind onto a set of small collector tiles made of diamond, silicon carbide, and diamondlike carbon. As long as the lid of the science canister was opened, the concentrator was exposed to the solar wind throughout the collection period.

On April 1, 2004, ground controllers ordered the robot spacecraft to stow the collectors and so its collection of pristine particles from the Sun ended. The closeout process was completed on April 2, when the Genesis spacecraft closed and sealed its sample return capsule. Then, on April 22, the spacecraft began its journey back toward Earth. However, because of the position of the landing site—the U.S. Air Force's Utah Testing and Training Range in the northwestern corner of that state—and the will gain very wide acceptance by the scientific community or the general public. For example, locating such a facility and all its workers in an isolated area on Earth actually provides only a small additional measure of protection. Consider the planetary environmental-impact controversies that could rage as individuals speculated about possible ecocatastrophes.

unique geometry of the Genesis spacecraft's flight path, the robot sampling craft could not make a direct approach and still make a daytime landing. To allow the Genesis chase-helicopter crews an opportunity to capture the return capsule midair in daylight, the Genesis mission controllers designed an orbital detour toward another Lagrange point, L2, located on the other side of Earth from the Sun. After successfully completing one loop around L2, the Genesis spacecraft was prepared for its return to Earth on September 8. On September 8, the spacecraft approached Earth and performed a number of key maneuvers prior to releasing the sample return capsule. Sample capsule release took place when the spacecraft flew past Earth at an altitude of about 41,000 miles (66,000 km). As planned, the Genesis return capsule successfully reentered Earth's atmosphere at a velocity of 6.8 miles per second (11 km/s) over northern Oregon.

Unfortunately, during reentry on September 8, the parachute on the Genesis sample return capsule failed to deploy (apparently because of an improperly installed gravity switch), and the returning capsule smashed into the Utah desert at a speed of 193 miles per hour (311 km/hr). The high-speed impact crushed the sample return capsule and breeched the sample collection capsule—possibly exposing some collected pristine solar materials to potential contamination by the terrestrial environment.

However, mission scientists worked diligently to recover as many samples as possible from the spacecraft wreckage and then to ship the recovered materials in early October to the Johnson Space Center in Houston, Texas, for evaluation and analysis. One of the cornerstones of the recovery process was the discovery that the gold foil collector was undamaged by the hard landing. Another postimpact milestone was the recovery of the Genesis spacecraft's four separate segments of the concentrator target. Designed to measure the isotopic ratios of oxygen and nitrogen, the segments contain within their structure the samples that are the mission's most important science goals.

The Genesis sample of extraterrestrial materials consisted of atoms collected from the Sun. NASA's planetary protection officer had categorized the mission as "safe for unrestricted Earth return." This declaration meant that exobiologists and other safety experts had concluded that there was no chance of extraterrestrial contamination during sample collection at the L1. The U.S. National Research Council's Space Studies Board also concurred on the planetary protection designation of unrestricted Earth return for the Genesis mission. The board determined that the sample had no potential for containing life. Consequently, there was no significant issue of extraterrestrial contamination of planet Earth due to the aborted sample return operation of the Genesis capsule. However, the issue of planetary contamination remains of concern when robot-collected sample capsules return from potentially life-bearing celestial bodies, like Mars and Europa.

What would happen to life on Earth if alien organisms did escape and went on a deadly rampage throughout the Earth's biosphere? As mentioned previously, dangerous alien microorganisms that have gone wild in the terrestrial biosphere has been a popular and recurrent science-fiction theme. Although causing no back contamination hazard, the unplanned, high-speed crash of NASA's Genesis spacecraft sample return capsule into the Utah desert on September 8, 2004, helped reinforce legitimate concern that if something might go wrong during a complex sample return mission—it can and often will. The alternative to this potentially explosive controversy is quite obvious: Locate the quarantine facility in outer space.

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