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08-Aug-01 | Delta flight 287 – Genesis

Delta threads a needle in both space and time!

With only a single 2-minute window on Wednesday, 8 August, sandwiched between flights of a Titan 4B and Space Shuttle Discovery, Delta flight 287 successfully launched Genesis on an accurate trajectory toward the L1 libration point between Earth and the Sun.

The terminal count was smooth and quiet, marred only by the momentary transgression of a boat into the “drop box,” or booster motor impact zone. After last week’s bouts with rain and heavy cloud cover, the weather forecast was mostly sunny, with a mere 10% chance of violating launch constraints (the inverse of the previous attempt).

Official liftoff time was 12:13:40.324 EDT. The 7326 vehicle leapt off the pad in its inimitable manner and punched through one of the small, puffy white clouds that drifted over the Cape, lending additional drama to the on-board aft-facing “videoroc” camera view. All staging events went nominally, though the first SECO came a few seconds earlier than expected, apparently due to an overly-energetic first stage firing. The parking orbit was judged perfect before the rocket passed out of range of the Antigua tracking station.

Next came a 46-minute coast phase, during which time Delta 287 was out of range of tracking stations. Then, as the vehicle passed over Australia, the second stage fired again, followed by the third stage, and the spacecraft was released. Its solar panels were soon deployed, and the first status check as Genesis passed over the Deep Space Network tracking station at Goldstone, California, showed the craft in a substantially healthy safe mode in preparation for its cruise.

This $209 million mission, part of the NASA Discovery Program, will take nearly three months to travel to the L1 Lagrange point, 930K miles from Earth between the Earth and Sun. From there, it will spend two-and-a-half years collecting particles of the solar wind. Interestingly, Genesis’ orbit has been designed so that after about 5 orbits, it will naturally leave L1 and travel to L2, where it will loop around and head for Earth with its prize, a mere 10-20 micrograms of starstuff. In September 2004, Genesis will parachute into the skies over Utah and be captured in midair by helicopter using techniques perfected in the 1960s during the NRO’s Corona project. Scientists hope the samples will provide clues to the origin and evolution of the solar system.

On Wednesday, 18 July, the payload (attached to its Star-37FM third stage motor) was placed in its protective canister. Early the next morning, it was transported from the PHSF to the pad and mounted to the vehicle stack. The 9.5-foot payload fairing was installed on Wednesday, 25 July. The Aerojet second stage was fuelled with its hypergolic propellants on Friday, 27 July. The Launch Readiness Review took place on 28 July, along with vehicle power-up, guidance system update, beacon checks and ordnance hookup. The 30 July launch attempt was scrubbed prior to launch day due to a power supply issue with the spacecraft’s star tracker. A similar power supply in a European satellite failed during radiation exposure testing, and a paper chase ensued to track the provenance of the twin units in Genesis. That resolved, on 1 August, thick cirrus clouds over Cape Canaveral’s SLC-17A violated launch constraints. The 2 August forecast was lousy enough to preclude an attempt. On Friday, 3 August, continuing thick clouds and potential precipitation again scrubbed the launch. Forecasters had predicted only a 10% of meeting launch weather criteria, but a busy schedule on the Eastern Range forced the Friday attempt.

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