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Genesis (spacecraft)

In its collecting configuration, the Genesis spacecraft exposed collecting wafers to the solar wind. (Courtesy NASA/JPL-Caltech)

The Genesis spacecraft was the first ever attempt to collect a sample of solar wind, and the first sample return mission to return from beyond the orbit of the Moon. It was launched on August 8, 2001, and crash-landed on September 8, 2004 after its drogue parachute failed to deploy. As of September 10 2004, analysis of the damaged capsule is in progress, and there is a possibility of retrieving partial science data from the mission.

Contents

1 Operation

1.1 Launch and sample collection
1.2 Sample retrieval
1.3 Sample extraction

2 Mishap Investigation Board

3 External links

Operation

Launch and sample collection

Genesis was a Discovery-class mission of the NASA Jet Propulsion Laboratory (JPL) at the California Institute of Technology (Caltech). The spacecraft was designed and built by Lockheed Martin Space Systems. According to NASA, the total cost of Genesis was $264 million.

NASA launched the craft on August 8 2001 from Cape Canaveral. Genesis went to the L1 Lagrange point between the Earth and the Sun. From December 3, 2001 to April 1, 2004 it exposed collector arrays to pick up atoms of solar wind expelled from the Sun.

There were three distinct collector arrays, with only one exposed at any time. The three arrays were each used to collect a different type of solar wind, with the exposure of the arrays controlled based on solar observations. Each collector array consisted of a grid of ultra-pure wafers of silicon, gold, sapphire, and diamond.

Sample retrieval

Following completion of the collection phase, the collector arrays were stowed in a sample return capsule, and the spacecraft returned to Earth. As the capsule was approaching Earth and at the first stages of re-entry all appeared well.

A normal parachute landing would have damaged the delicate samples, so the mission design called for a mid-air retrieval of the sample return capsule. About 30 km above the ground, a drogue parachute was planned to be deployed to slow descent. Then, at a height of 2.5 km, a large parafoil was to be deployed to slow descent further and leave the capsule in stable flight. A helicopter flown by a stunt pilot, with a second helicopter as a backup, was then to attempt to catch the capsule by its parachute on the end of a 5 metre hook. Once retrieved, the capsule would have been soft-landed.

The sample return capsule entered Earth's atmosphere on September 8, while the remainder of the spacecraft was diverted into an irretrievable sunward orbit to avoid atmospheric entry. Deployment of the parachutes failed, with none of the pyrotechnic devices firing, and the spacecraft descended slowed only by air resistance. The planned mid-air retrieval could not be carried out. The spacecraft crashed into the desert floor of the Dugway Proving Ground in Tooele County, Utah at about 86 m/s (311 km/h; 193 mph), creating a small but spectacular crater.

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 muddy ground. The cause of the pyrotechnic failure has not yet been determined, but it is suspected to be due to failure of the battery that was intended to detonate the explosives.

Colin Pillinger is part of the science team analysing the collected samples. Professor Pillinger was the Principal Investigator for the ill-fated Beagle 2 mission to Mars (planet). It has been suggested that the cause of Beagle 2's loss (which is as yet undetermined) may also have been due to a parachute failure.

Sample extraction

The damaged capsule was moved to a clean room for analysis, and the unfired pyrotechnic devices safed. Initial investigations showed that some wafers had crumbled to dust on impact, but others were largely intact. Desert dirt entered the capsule, but not liquid water. Because the solar wind particles are expected to be embedded in the wafers, whereas the contaminating dirt is likely to just lie on the surface, it may be possible to separate the dirt from the samples.

The analysis team is hopeful of being able to extract some useful data from the capsule. Roger Wiens, of the Los Alamos National Laboratory stated on September 10 2004 that because much of the inner canister was still intact, and despite serious contamination, "We should be able to meet many, if not all, of our primary science goals.". On September 21 2004 the extraction was said to be going well, with wafer fragments beginning to be extracted from the science canister.

Mishap Investigation Board

A 16-member NASA Genesis Mishap Investigation Board (MIB) was quickly formed, including experts on pyrotechnics, avionics, and other relevant specialities. The MIB started its work on September 10 2004 when it arrived at Dugway Proving Ground. It determined that all scientific hardware meant to be curated by the Johnson Space center can be released and are not needed for the work of the board. Both JPL and Lockheed Martin have begun to prepare flight data and other records for the MIB.

It was announced on September 23 2004 that the capsule, having had the science material extracted, would in the next week or so be moved to the Lockheed Martin Space Systems facility near Denver, Colorado.

External links