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| James Bell, assistant professor of astronomy at Cornell and a member of the CONTOUR science team, and his son, Dustin, 11, react with delight and awe as the Boeing Delta II rocket soars skyward July 3. Photos by Robert Barker/University Photography |
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With a flash of white-hot light and a towering cloud of smoke in its wake, the Boeing Delta II three-stage rocket roared into the sky from Launch Pad 17A at Cape Canaveral Air Force Station, Fla., at 2:47:41 a.m. Wednesday, July 3. With it, the rocket carried Cornell astronomers' hopes for a spectacular four-year voyage of discovery to two, and possibly three, comets.
To cheers and cries of awestruck delight from nearly 400 alumni, friends and faculty who were present for the launch, the Cornell-led NASA mission, called the Comet Nucleus Tour (CONTOUR), soared into the predawn sky from its floodlit launch pad with a heart-stopping roar and a pyrotechnical display.
"Awesome, cool. We're flying. We're in space," said James Bell, Cornell assistant professor of astronomy, who is a member of CONTOUR's science team.
The launch of the spacecraft was a spectacular success for the mission's principal investigator, Joseph Veverka, Cornell professor of astronomy and department chair, and members of his international science team, who will be analyzing the data the spacecraft sends back to Earth for several years to come.
"That's the most spectacular thing I've ever seen," said Ann Harch, Cornell researcher and mission programmer. "I've seen two day launches, and they were great. But tonight, the bright, white light hung there above the pad seemingly forever -- and then it took off."
One hour and 3 minutes after launch, the CONTOUR spacecraft separated from the third and final stage of the launch vehicle and now is in an elliptical Earth orbit. The spacecraft sent its first signal to the Deep Space Network antenna in Goldstone, Calif., at 5:45 a.m. EDT July 3.
Starting next year, Cornell researchers hope to discover much new information about the heart of a comet, the nucleus, and even to gain a glimpse of the dawn of the solar system and perhaps a snapshot of how the Earth was formed and life began.
"Comets are the solar system's smallest bodies but among its biggest mysteries," said Veverka. "We believe they hold the most primitive materials in the solar system and that they played a role in shaping some of the planets, but we really have more ideas about comets than facts."
The launch came after a two-day delay resulting from the discovery June 27 of dust contamination on the spacecraft's solar panels as CONTOUR sat on top of the 13-story rocket. Technicians and scientists feared that the dust would impede the solar panels' ability to capture energy and would ruin the ability of the spacecraft's four scientific instruments to gather data, including visual images and analysis of comets' dust and gas. The new launch date was scheduled for July 3.
Then, as that date approached, thunderstorms, with lighting flashing in the distance, moved into the area around Kennedy Space Center, threatening further delays. But later the weather began to cooperate, and the launch was given the final weather "green light" only 13 minutes from liftoff -- providing a glorious pre-Independence Day.
Meanwhile, back in Ithaca on launch day, after a long night of anticipation, Cornell professor of astronomy Steven Squyres was wide awake and optimistic by 10 a.m. to brief Ithaca-area news media on the CONTOUR launch and what comes next. Narrating a video of the launch, Squyres relayed the anticipation experienced by the approximately 20 astronomy department faculty, staff and students who witnessed the launch at the Cape and another 30 in the Space Sciences Building on campus in Ithaca. All the "launch criteria," including favorable weather, he said, were met only 13 minutes before the scheduled liftoff time. The booster rockets burned for about one minute before being jettisoned from the main Delta rocket, and there was "a very long 19 minutes" until NASA ground controllers could establish communication with the spacecraft, Squyres said. "Yes, I was holding my breath a little."
The CONTOUR spacecraft, designed and built by the Johns Hopkins University Applied Physics Lab, the manager of the mission, will remain in Earth orbit until Aug. 15, when its main engine fires and the spacecraft begins its cosmic adventures. First it will encounter comet Encke on Nov. 12, 2003, speeding through the comet's tail at 60,000 miles per hour and passing the comet's icy, rocky nucleus at a distance of only 100 kilometers (62 miles). Not only will the spacecraft obtain the closest images yet of a comet's nucleus, but it will analyze the surrounding gas and dust. The mission's next stop will be comet Schwassmann-Wachmann (SW) 3 on June 19, 2006. CONTOUR also has the flexibility to chase new comets arriving from the Oort Cloud, the cometary nursery on the outskirts of the solar system.
The spacecraft with its instruments weighs 2,138 pounds, and it is carrying 176 pounds of hydrazine fuel. It is an eight-sided structure, surrounded by solar panels to provide power for the instruments. The bottom of the craft, the side facing the comet, is covered with a 10-inch-thick blanket of Nextel and Kevlar fabric to prevent cosmic or cometary dust from penetrating the spacecraft. Without that shielding, said Veverka, it would be like "sitting in a vacuum and taking a .22-caliber bullet."
Besides worrying whether the specially designed equipment on CONTOUR will work, Squyres said, the team will share the concern of all parents with young drivers in the family -- collisions. Although the craft is protected from comet particles by its sturdy Nextel and Kevlar shield -- and while Encke is an older comet with a single, relatively stable nucleus -- the SW3 nucleus split apart in the mid-1990s, and a close approach could be perilous. "There is a chance we [the CONTOUR spacecraft] could be hit by a chunk of something," Squyres told news reporters. "If we're hit by a chunk the size of a truck, the mission is over. But we will have learned something."
If CONTOUR successfully eludes comet chunks, the close approach should yield views and unprecedented data on "fresh, new material from the nucleus of a comet," Squyres predicted. "And if a 'new' comet is discovered in the course of the mission," he added, "there is a high probability we can change CONTOUR's path and fly by."
The successful launch was a milestone in a scientific journey that began in 1997 when Cornell's proposal to manage the $159 million CONTOUR mission, under principal investigator Veverka, was accepted by NASA, and preparatory work began. But even during CONTOUR's hibernation periods, Cornell space scientists won't be snoozing, Squyres reminded the Ithaca reporters: Coming up next, between May and July 2003, two rover vehicles are scheduled for launch to explore the surface of Mars. Squyres, who is the principal investigator for the Athena science package to be carried by the two rovers, expects to be holding his breath once again on Jan. 4 and Feb. 8, 2004, when the rovers are scheduled to reach the red planet.
At a press conference two days before the CONTOUR launch, Veverka explained the scientific importance of comets. Comprehending comets means understanding ourselves and our natural history, he explained. Perhaps, he said, comets brought the water and other biological ingredients to start life on Earth. And if they started life here, the comets likely started life elsewhere in the cosmos, he said.
Michael Belton, the mission's assistant principal investigator and a former University of Arizona researcher, explained that if CONTOUR makes new discoveries, he, for one, would enjoy the unexpected. "I'd like to see our theories somewhat off-base. I'd like to see an overturning of current paradigms with the honest truth," he said.
The launch was the culmination of more than two decades of planning for Veverka, who has long dreamed of a voyage to comets. As a doctoral student at Harvard University under Fred Whipple, the father of modern cometary studies, Veverka first began to appreciate the importance of comets in the solar system and to life on Earth. Now he will be the first to see the raw data and images sent back from the spacecraft to the CONTOUR science data center in the Space Sciences Building at Cornell. He will be joined in the analysis by members of the CONTOUR science team, including Cornell researchers and astronomers Peter Thomas and Brian Carcich, as well as Squyres, Harch and Bell.
At a briefing at the Kennedy Space Center hours before the launch, Veverka spoke for all his colleagues when he told the rapt audience of Cornellians, "I don't know about you, but I'm darned excited."
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| The view from the launch pad's perimeter at 2:47 a.m., taken by a remote-control camera. |
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