Genesis (Discovery 5)

Launch data: Designation  26884 / 01034A Launch date  08 Aug 2001 - 16:13:40 UT Launch site  CC, SLC-17A Launch vehicle  Delta-2 (7326-9.5) (#D287) Mission  Solar exploration Earth-Sun L1 Point Operator   Heliocentric orbit Perihelion / Aphelion   Incl. to ecliptic   ° Period   min

The Genesis trajectory

Description:

• Genesis will fly to the Earth-Sun L1 point and spend two years collecting samples of the solar wind. A follow on to such experiments as the solar wind collectors exposed on the Moon by Apollo astronauts, Genesis will allow scientists to determine the chemical and isotopic composition of the Sun. The collected samples will be physically returned to Earth (landing in Utah) and analysed in ground-based laboratories. Among the goals are an attempt 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.
• Genesis is part of NASA's Discovery program. The spacecraft and sample return capsule were built by Lockheed Martin Astronautics. The vehicle will enter a 6-month-period halo orbit around L1 with a radius of 800000 km when it arrives on station later this year. The craft carries a pure hydrazine propulsion system, and a sample return capsule with deployable sample collection plates and an ion concentrator that rejects protons (80 percent of the solar wind) in favour of the trace elements it is trying to study.

Mission details:

• The Genesis probe was launched from Cape Canaveral on Aug 8, 2001.
• Launch was by a Boeing Delta 7326 vehicle, a Delta II variant with three strap-on motors and a lightweight Star 37 third stage. The first burn of the Delta second stage put Genesis in a 185 x 197 km x 28.5 deg parking orbit at 1624 UTC. At 1712 UTC the second burn raised the orbit to 182 x 3811 km, and at 1713 UTC the third stage fired to put Genesis on its trajectory to L1 with a nominal apogee of around 1.2 million km.
• Following launch, Genesis cruised to the Earth L1 then performed a Lissajous orbit insertion maneuver, entering an elliptical orbit about L1 on November 16, 2001. Genesis exposed its collector arrays to pick up solar wind particles expelled from the Sun on December 3, 2001. The collection process ended after 850 days, on April 1, 2004, with the spacecraft completing five halo loops around L1. Genesis began its return to Earth on April 22, 2004. The return phase included an orbital detour toward the Earth L2 so that the craft could be recovered during the daytime, as a direct approach precluded this possibility. After completing one halo loop about L2, then returned to Earth for a planned September 8, 2004 recovery.
• On Sep 8, 2004 the Genesis space probe became the first artifact to return from beyond lunar orbit to the Earth's surface. Unfortunately, the parachute system failed to deploy and the capsule hit the Utah desert at high speed. The capsule is embedded in the desert floor and is split open; it is not yet clear to what extent the solar wind samples have been ruined.
• After targeting maneuvers on Aug 9, Aug 29, and Sep 6, 2004 the Genesis Sample Return Capsule (SRC) separated from the Genesis spacecraft at around 1153 UTC on Sep 8, 66000 km above the Earth. At 1215 UTC the spacecraft made a small separation burn, and the bus maneuvered to miss the Earth. In fact, the Genesis probe had to burning up over the Pacific.
  At 1555 UTC the SRC entered the atmosphere over Oregon at about 11 km/s (Earth-relative) and an angle of 8.25 degrees below the horizontal, giving an orbital perigee close to zero and an apogee around 1.5 million km. The SRC's heat shield protected it through atmospheric entry. A mortar which was intended to release the drogue parachute at 33 km high failed to fire and at 1558 UTC the tumbling SRC impacted the Dugway Proving Ground at the Utah Test and Training Range at 40 07 40N 113 30 29W. Impact velocity was around 40 to 90 m/s, over 200 times slower than it was travelling a few minutes earlier but still more than enough to wreck the vehicle.
• Genesis SRC (Sample Return Capsule): 28453 / 01034D
  
  

  The Genesis sample return capsule tumbles to Earth only moments before it crashed

  The sample return capsule crashed into the Utah desert floor, breaking open the capsule. The capsule is about 1.5 m in diameter and has a mass of 275 kg.

  
  
• GENESIS Mishap Report
• Fate of spacecraft bus:
  
  • The Genesis sample return capsule was ejected from its parent spacecraft at 1153 UTC on September 8, 2004 at an altitude of 59600 km, and entered the atmosphere four hours later at 1555 UTC. Meanwhile, the spacecraft bus made a course change at 1208 UTC, at an altitude of 56700 km, to raise its perigee from a few kilometers below the Earth's surface to a height of 242 km, allowing it to just miss the atmosphere and head out to deep space. The incoming trajectory was a geocentric orbit of around -1 x 1376362 km x 52.0 deg, with the 'vacuum perigee' (the path the return capsule would have taken if Earth didn't have an atmosphere) grazing the surface of the Earth. The perigee raise burn changed this to a 242 x 1350949 km x 52.0 deg orbit, missing the atmosphere nicely at 1558 UTC. The Genesis bus passed lunar orbit outbound early on Sep 11.
  • It reached apogee at 1.28 million km on Oct 7, 2004 and fell back to perigee on Nov 6, by which time lunisolar perturbations will have changed the orbit to 60672 x 1454293 km x 41.9 deg, when its orbit was tweaked to ensure departure from the Earth-Moon system on Nov 17. It is now (Jan 2005) in a 0.896 x 0.990 AU orbit around the Sun inclined 0.28 deg to the ecliptic, according to data on JPL's Horizons system.
  • Final commands were radiated on December 2, 2004, to put Genesis into hibernation. While in this "safe" mode, it will continue transmitting health and safety information, autonomously pointing its solar arrays toward the Sun. The spacecraft bus left L1 around February 1, 2005, staying in a heliocentric orbit leading the Earth.
  • An extended `Exodus' mission for solar wind monitoring has been proposed which would have used a small burn to put the Genesis bus in a solar orbit nearthat of the Earth.