Genesis (probe)

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Genesis (probe)

Genesis during sample collection
(drawing, NASA)
NSSDC ID 2001-034A
Mission goal Exploring the solar wind
Client National Aeronautics and Space AdministrationNASA NASA
Launcher Delta II missile 7326
Takeoff mass 636 kg
Course of the mission
launch pad Cape Canaveral SLC-17A
08/08/2001 begin
11/16/2001 Reaching the L1 point
12/03/2001 Open the collector
04/01/2004 Closing the collector
09/08/2004 Return capsule
Flight profile of Genesis
The recovery probe was supposed to be hooked up from the helicopter on September 8, 2004, ...
(recording of an exercise)
... but the parachute did not open. The probe crashed to earth unchecked, as the picture of the crash site shows.
Above: View of the inside of the return capsule
Below: The same type of acceleration sensor, which was installed the wrong way round.

Genesis (named after the first book of the Bible ) was a NASA space probe mission to study the solar wind . The probe lifted off from Earth on August 8, 2001 at 16:13:40 UT with a Delta II rocket 7326 (3 solid fuel boosters and a third stage with a Star 37FM engine). It reached its final position, the Lagrange point L 1 of the sun - earth system, in November 2001.

On-board instruments

There were four instruments on board the probe:

  • Three high-purity collector arrays made of gold , sapphire , silicon and diamond , among other things . Between December 3, 2001 and April 1, 2004, they caught the particles of the solar wind . Each of these arrays was exposed to one of the three different solar wind regimes. These arrays were returned to Earth in a sample capsule, but were damaged and contaminated by the unchecked impact.
  • An ion detector that determines the velocity, density, temperature and approximate composition of the ion component.
  • An electron monitor that determines the energy and density of electrons.
  • An ion concentrator that filters out elements such as oxygen and nitrogen and directs them to a special collector.

Mission history

After take-off, the probe began its three-month journey to the L 1 point. There she fired her hydrazine thrusters for 268s and entered a halo orbit around it. Then began u. a. the collection of solar wind particles. In over 30 months, Genesis completed 5 full Halo orbits. In April 2004 the sample collection container was closed and sealed. After the return capsule with the samples was deployed on September 8 at around 12:00 UT, the Genesis mother probe was placed in an orbit around the sun ahead of Earth.

On September 8, 2004, the capsule with the collectors fell to the ground in the desert of Salt Lake City without the parachutes opening. A helicopter should have caught the sample container in the air and brought it safely to the ground.

The sample capsule hit a base of the US Army (Utah Test and Training Range) at approx. 311 km / h, so emergency services could quickly examine the capsule. The collectors, which contained the captured solar wind, were destroyed or contaminated by the earthly atmosphere and dust, because the hermetic sealing of the capsule was no longer given after the impact.

research results

According to an official statement from NASA, parts of the collectors have remained intact. The recovered remains of the collector container were examined in a clean room with various methods in order to clean the collectors contaminated by earthly dust. The small amount (approx. 3–4 micrograms) and depth of penetration of the captured solar particles proves to be problematic.

The penetration depth is typically only 10 nanometers. Nevertheless, particles of the solar wind could already be clearly isolated, since the pollution only affects the surface. 15,000 fragments could be recovered. Their size measures at least 3 millimeters and only a few centimeters. They went to 16 laboratories for examination.

In the meantime (June 2011) the atoms from the sun could be separated from the earthly impurities and prove that the sun - like the gas planets - has a significantly different isotope distribution than the inner planets.

Accident investigation

To clarify the failure of the landing parachutes, NASA immediately set up a commission of inquiry. Their results influence security considerations for the similarly designed Stardust mission and the planning of future “sample return” missions. The first indications indicated a technical failure of the control mechanisms of the probe. The preliminary result of the investigative commission indicated a design flaw in the accelerometers , which were installed incorrectly. With the completion of the investigation almost two years after the crash, this assumption was confirmed: A sensor for measuring the acceleration due to gravity , which was supposed to trigger the braking parachutes, was installed the wrong way round. Because of the time pressure in the construction of the 260 million dollar probe, the manufacturer Lockheed Martin had waived a comprehensive test, in which this would have been noticed, and was satisfied with a simpler one.

See also

Web links

Commons : Genesis (probe)  - album with pictures, videos and audio files
  • NASA - JPL (English)
  • Bernd Leitenberger: Genesis. In: November 20, 2017 (Detailed description of the Genesis mission).;
  • Sven Piper: Genesis Mission. In: March 21, 2019 .;
  • Video of the serve. ( mov-video , 6.1 MB) In: Archived from the original on October 16, 2004 .;

Individual evidence

  2. Christoph Seidler: Structure of the solar system: Crash probe "Genesis" reveals its secrets. In: Spiegel Online . June 24, 2011. Retrieved June 24, 2011 .