Status: Operational 2001. First Launch: 2001-08-08. Last Launch: 2001-08-08. Number: 1 . Gross mass: 636 kg (1,402 lb).
A follow on to such experiments as the solar wind collectors exposed on the Moon by Apollo astronauts, Genesis would allow scientists to determine the chemical and isotopic composition of the Sun. The collected samples were to be physically returned to Earth (air-snatch recovery over Utah) and analyzed in ground-based laboratories. Among the goals were to study why the oxygen isotopic composition seems to vary in the solar system, accurate measurement of argon, xenon and neon abundances, and isotope ratio abundance measurements accurate to one percent for a broad range of elements.
The spacecraft and sample return capsule were built by Lockheed Martin Astronautics; mass was 494 kg dry (including the 220 kg return capsule), 636 kg at launch. The craft was 1.3 m high with a 1.52 m diameter capsule, and had a 6.8 m span when deployed. The vehicle was to enter a 6-month-period halo orbit around L1 with a radius of 800,000 km when it arrived on station. The craft carried a monopropellant hydrazine propulsion system, and a sample return capsule with deployable sample collection plates and an ion concentrator that rejected protons (80 percent of the solar wind) in favor of trace elements.
The wide angle collector was a circular mosaic of one meter diameter consisting of many hexagonal tiles made of diamond, gold, ultra-pure silicon, sapphire, aluminum or germanium. All kinds of ions were to be implanted in the wide angle collector whereas the carbon, nitrogen and oxygen ions were to be focused onto the concentrated-ion collector made up of hexagonal shaped diamond or silicon carbide tiles. The focused enhancement of these ions was necessary since the collecting wafers may contain nontrivial amounts of earthly contamination of these elements. This focusing was enabled by a parabolic mirror, with the positive voltages confined to numerous tiny segments on its surface. The paraboloid was to focus very little of the solar light/heat. A total of 10-20 micrograms of ions were to be collected by both collectors during the 30 months of exposure. The ion spectrometer was to monitor all species with energy greater than about 1 keV, and the electron spectrometer the smaller energy range electrons. (The solar wind speed was about 400 km/s and the protons in it were at about 1.0 keV with the heavier ions and the electrons having energies proportional to their masses.) The spectrometer data were to be telemetered in the S-band, and the re-entering sample canister was to parachute over Utah state in early September 2004, where it was to be grabbed by a helicopter.
The Project Scientist and Principal Investigator for Genesis was Donald Burnett, California Institute of Technology, and the Lead Investigator for the concentrated-ion collector and the two spectrometers was Roger Wiens of the Los Alamos National Laboratory. The returned samples was to be stored at Johnson Space Center for analysis and distribution. The Project Manager for the mission was Chester Sasaki of the Jet Propulsion Laboratory.
NASA NSSDC Master Catalog Description
The parachute on the Genesis sample return capsule failed to deploy on re-entry. The capsule crashed in the Utah desert. The fragments from the sample return container have been packaged for shipment to Johnson Space Center's curation facility in early October. Scientists are optimistic that they will be able to salvage useful data from the samples.
The primary objective of the Genesis mission is to collect samples of solar wind particles and return them to Earth for detailed analysis. The science objectives are to obtain precise measurements of solar isotopic and elemental abundances and provide a reservoir of solar matter for future scientific analysis. Specifically, the primary scientific objectives were to obtain precise measurements of isotope ratios of oxygen, nitrogen, and solar wind isotopic fractionation. Study of these samples will allow testing of theories of solar system formation and evolution and early nebular composition. A total sample mass of roughly 10 to 20 micrograms is expected.
The Genesis spacecraft has a launch mass of 636 kg, including 142 kg of fuel, and consists of a 2.3 meter long, 2 meter wide spacecraft deck with two fixed solar panel wings with a total span of 7.9 meters and a sample return capsule mounted on top of the deck. The spacecraft is spin stabilized at one revolution every 37.5 seconds. Propulsion is provided by a hydrazine monopropellant thruster using a helium pressurant. Communication is S-band via a fixed antenna. The solar panels provide a maximum of 254 Watts power to a nickle-hydrogen storage battery. Temperatures are maintained by heaters and passive thermal control. The spacecraft is also equipped with ion and electron electrostatic monitors to determine which solar wind regime is being encountered and to help set the appropriate collector voltage. Spacecraft subsystems and monitors are mounted beneath the sample return capsule.
The sample return capsule is disc-shaped with a blunt conical top and bottom, 1.5 meters in diameter and 1.31 meters high, with a total mass of about 225 kg. It contains a 97.3 cm diameter science cannister which holds a concentrator and three collector arrays. The collector arrays are flat discs made of ultra-pure silicon, silicon carbide, germanium, sapphire, chemically deposited diamond, gold, aluminum, and metallic glass wafers which are exposed to the solar wind. Isotopes of helium, oxygen, nitrogen, neon, radon, and other elements are implanted in the top 100 nm of these materials. The concentrator is an electrostatic mirror which concentrates elements up to neon by a factor of approximately 20. Each collector array is to be deployed for a different solar wind regime.
Genesis launched successfully at 16:13:40.324 UT on 8 August 2001 on a Delta 7326 (a Delta II Lite launch vehicle with three strap-on solid-rocket boosters and a Star 37FM third stage). Approximately 1 hour later the spacecraft left low Earth orbit on a three month journey out towards the L1 Lagrangian Sun-Earth libration point, 0.01 AU from Earth, to be inserted into a halo orbit about the L1 point. The L1 point is beyond the influences of the geomagnetic field and its trapped particles. Genesis reached the L1 point on 16 November 2001 and fired its hydrazine thrusters for 268 seconds to insert itself into the halo orbit at 19:03 UT (2:03 p.m. EST). On 3 December 2001 it opened its collector arrays and began gathering samples of solar wind particles. It completed 5 halo orbits over 30 months collecting samples. In April of 2004 it ended sample collection and shut the door to the sample collection cannister.
The samples were stowed and sealed in the contamination-tight canister within the Sample Return Capsule and returned to Earth over a five month period, flying past the Earth and then returning in order to be positioned for daylight entry. On 8 September 2004 the sample return capsule was released from the main spacecraft bus at about 12:00 UT and re-entered the Earth's atmosphere at 15:52:47 UT (11:53 a.m. EDT, 9:53 a.m. local MDT) and should have deployed a drogue parachute 2 minutes 7 seconds after entry at 33 km altitude. The parachute never deployed and the capsule crashed in the desert at a speed of 311 km/hr, severely damaging the capsule. The science cannister was removed to a clean room and the sample collection fragments are now ready to be shipped to Johnson Space Center. The cause of the parachute failure is believed to be incorrectly installed accelerometers which were to deploy the parachutes. The science team is confident that most of the planned science can be recovered from the salvaged sample collectors.
The spacecraft bus looped around Earth after the capsule was released and headed back out towards the L1 point.
The original plan for re-entry was as follows: Six minutes after drogue chute deployment the main parafoil was to deploy at an altitude of 6 km over the U.S.A.F. Utah Test and Training Range, where it would be aerocaptured by one of two specially equipped helicopters at an altitude of about 2.5 km. The spacecraft had the capability of going into a parking orbit if the weather at the capture site was unsuitable. The capsule was taken to a clean room at the U.S. Army Dugway Proving Ground and will be transported to Johnson Space Center for contamination control and curation, and distributed to selected Advanced Analytical Instrument Facilities for analysis.
There was some concern that the sample return capsule battery would fail, jeopardizing the re-entry. The battery was overheating in space, but ground tests showed that the battery should have been unaffected by the amount of heating it had endured, and should have operated to deploy the parachute on reentry. The actual cause of the parachute deployment failure is not known at this time.
Genesis was the fifth launch in NASA's Discovery program. The total cost of the project is $164 million for spacecraft development and science instruments and $45 million for operations and science data analysis.
Credit: Manufacturer Image
Launch delayed from February 10 and July 30. The Genesis probe flew to the Earth-Sun L1 Lagrangian point and spend two years collecting samples of the solar wind. The collected samples were to be physically returned to Earth in a sample return capsule (air-snatch recovery was planned over Utah) and analysed in ground-based laboratories. The first burn of the Delta second stage put Genesis in a 185 x 197 km x 28.5 deg parking orbit at 1624 GMT. At 1712 GMT a second burn raised the orbit to 182 x 3811 km, and at 1713 GMT the third stage fired to put Genesis on its trajectory to L1 with a nominal apogee of around 1.2 million km. By the first week of November 2001 Genesis arrived at the Earth-Sun L1 point. A malfunctioning thermal radiator caused some concern for the health of the sample return capsule's critical battery, which was overheating, but Genesis began collecting solar wind samples on schedule.
On September 8, 2004, the Genesis space probe became the first spacecraft to return from beyond lunar orbit to the Earth's surface. The Genesis Sample Return Capsule separated from the spacecraft on September 8, 66,000 km above the Earth. The capsule successfully re-entered the atmosphere over Oregon at 11 km/s, but a wiring error resulted in the drogue parachute release mortar failing to fire at 33 km altitude. The capsule crashed to earth at 90 m/s in the Dugway Proving Ground at 40 07 40 N 113 30 29 W. Although the vehicle was smashed, some of the samples could be retrieved.