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Archive for 2001

20-Aug-01 | FUSE detects possible comet cloud

20-Aug-01 FUSE (Delta 271) has detected what scientists believe to be a cloud of comets, similar to our own Sun’s Kuiper Belt, surrounding the star Beta Pictoris. The discovery provides clues to how solar systems evolve. (Nature, 16-Aug-01, summary here.)

18-Aug-01 | Juggling act to take place at Vandenberg Air Force Base.

Spacecraft delays with the TIMED/Jason-1 mission will cause Boeing engineers to destack the vehicle currently on the pad at Space Launch Complex 2 West. Another Delta rocket will take its place as the commercial imaging satellite QuickBird 2 moves up to first in line.

Meanwhile, it appears Aqua will once again be pushed back to early 2002. Originally planned for launch late in 2000, Aqua’s launch has progressively moved to May, July, and September 2001; first quarter of 2002; and most recently December 2001. (Note that Goddard is presently under a denial-of-service attack by the Code Red virus and the Aqua site, along with most other internal gsfc.nasa.gov sites, may be unavailable for the near future.)

Specific launch dates have yet to be determined.

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.

03-Aug-01 | MAP performs lunar swing-by

On Monday, 30 July, MAP successfully flew about 3,200 miles from the surface of the Moon, receiving a gravitational boost that will accurately propel the spacecraft to L2. It should reach its operational orbit in a couple of months.

03-Aug-01 | 20,000 site hits

This week, History of the Delta Launch Vehicle received its 20,000th hit since it was first posted 3 years 8 months ago. Thanks for visiting!

01-Aug-01 | Jason-1 arrives at Vandenberg

The Jason-1 satellite has arrived at Vanderberg Air Force Base in preparation for launch later this fall. (JPL News Release, 31-Jul-01)

13-Jul-01 | Japan’s Delta rockets

A new addition to History of the Delta Launch Vehicle is now available. “N-I, N-II, and H-I: The Nippon Delta” is a brief description of the licensed Delta copies that launched Japan into the space age. This is a work in progress and as always, comments are welcome and invited.

01-Jul-01 | Delta flight 286 – MAP

Another perfect flight for Delta II as MAP reaches orbit! The 286th Delta launch lifted off from Space Launch Complex 17B at Cape Canaveral Air Force Station on Saturday, 30 June, at 15:46:46.183 EDT. It carried NASA’s Microwave Anisotropy Probe into a nominal, highly elliptical orbit and released the spacecraft about 85 minutes after launch.

MAP is a $145 million mission to map the entire sky in terms of the temperature fluctuations of the cosmic microwave background radiation. It will help to answer questions about the Big Bang theory and galaxy formation that were hinted at by COBE (Delta 189) in 1992.

The spacecraft, following checkout at SAEF-2, was stacked atop the Delta third stage, a Thiokol Star 48B solid-fuel motor, on 15 June. The following week it was packed in its protective canister, transported to SLC-17B and hoisted to the top of the Delta II vehicle. On Tuesday, 26 June, the 10-foot diameter composite payload fairing was installed.

This vehicle, a model 7425-10, is the first example of its type. NASA’s two 1998 Mars probes each used this same three-stage vehicle with four booster motors, but were protected by the standard 9.5-foot steel fairing. The Globalstar launches each used a composite fairing atop a two-stage 7420, which is identical in external appearance to the rocket flown today.

Saturday’s operations began early, as first stage fuelling commenced around 6 a.m. This was prior to Mobile Service Tower rollback and was meant to weigh down and steady the lightweight vehicle against the blustery conditions at the Cape all morning. Even with this precaution, tower cameras showed an occasional, slight rocking motion of the vehicle, while the many umbilical connections swung steadily back and forth in the breeze. Thunderstorms, a common occurrence in the Florida afternoons this time of year, were a concern all day. Launch Weather Officers kept a close eye on a bank of thunderhead clouds hovering north of Orlando, but luckily their anvil tops were not dragged eastward far enough to hold the countdown. Meanwhile, range operations kept a strict perimeter watch against the many pleasure boats out on a warm and mostly sunny weekend day, including a local fishing tournament that (from the sound of it) seemed to stay well clear of the exclusion zone.

The only minor glitch that cropped up in the 150-minute terminal count was due to some noisy data returned during the second stage engine slew tests. Controllers re-ran the tests and determined the noise was in the telemetry and that the yaw actuator was functioning normally. The count was not affected.

Flight 286 lifted off at the opening of its window with its RS-27A main engine, two steering verniers, and all four GEM-40 booster motors firing. The boosters burned out and were jettisoned just over a minute later. The first stage flight time was fairly typical at 4 minutes 35 seconds. The second stage then took over for another 7 minutes, followed by a long, 66-minute coast phase. The second stage restarted briefly for 4 seconds to boost the apogee by about 60 nautical miles, after which the third stage and payload spun up and accelerated for just under 90 seconds. Spacecraft separation came at 87 minutes, 50 seconds into flight, and at T plus 93 minutes the MAP flight team received word that the solar arrays on the probe had successfully deployed.

Over the next few weeks, MAP will fly three highly-elliptical “phasing” orbits as the Moon moves around its orbit to the proper position. Then, in August, MAP will receive a lunar gravity assist that will slingshot the probe to the L2 Lagrange point, a locale of orbital stability a million miles away from Earth in a direct line away from the Sun. While a few spacecraft, including SOHO and ACE (Delta 247), are in orbit around the L1 Lagrange point between the Earth and Sun, MAP marks the first time a spacecraft will attempt to orbit L2.

From there, MAP will continue the research first begun in earnest by COBE, the Cosmic Background Explorer, which launched aboard Delta 189 in 1992 and carried three primary instruments, each of which yielded a major cosmological discovery. MAP’s primary sensor, a bank of passively-cooled radiometers, is a follow-on to COBE’s Differential Microwave Radiometer and will map the complete sky in microwave wavelengths with a sensitivity far surpassing that returned by COBE (in terms of both temperature variation and angular resolution). The results are expected to add evidence for or against several cosmological theories as to the formation and expansion of the universe.

08-Jun-01 | NASA approves MESSENGER

Another NASA go-ahead for full-scale development has been announced, this time for MESSENGER, a $256 million mission that will be the first to orbit the planet Mercury. Mariner 10, the only other spacecraft to study Mercury, made three fly-bys in 1974-75. MESSENGER, which will spend one Earth year in orbit to compile a complete global map of the Sun’s closest neighbour, is scheduled to launch in March 2004 aboard a three-stage Delta II using the higher-powered GEM-46 booster motors of Delta III. (NASA Press Release, 07-Jun-01, refers to this as the seventh NASA Discovery mission, a distinction arguably held by Deep Impact.* Ultimately this discrepancy will be resolved by which program suffers fewer delays and launches first.)

08-Jun-01 | Boeing to change the Delta vehicle numbering system!

One of the curators of the Deep Impact web site has passed along the following, which she received while following up on an e-mail I sent correcting the use of 2925 as the Delta II vehicle designation:

This author has mixed feelings about the change, though I can concede the new system may reduce confusion in the user community. It remains to be seen how the four-digit system will be used to describe the various models of the Delta IV.

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