Our little home town newspaper had a nice article about Deep Impact, locally slanted. I must get a very early edition of the Denver Post, because its article, below the fold, was headlined “NASA waits for word on comet impact”, which means it must have been filed before midnight. By now, they’ve noticed that it worked.

Times-Call article (since they don’t archive at all):

3-2-1 contact
Ball cheers Deep Impact’s successful collision with Tempel 1
By Victoria A.F. Camron
The Daily Times-Call
BOULDER—Ball Aerospace employees cheered wildly Sunday night when they saw pictures of the Deep Impact spacecraft collide with Comet Tempel 1 about 83 million miles away from the Sommers-Bausch Observatory at the University of Colorado.

While dozens of employees crowded into a small room at the observatory, hundreds of interested visitors stood nearby in the Fiske Planetarium to watch a NASA TV telecast of the event, the first time humans have contacted a comet. The goal is to learn about the elements hidden inside comets—the same elements that may have been the beginning of life on earth.

In the observatory, a nearly silent crowd watched the impactor, as the spacecraft was called, take its last photos of the comet before it crashed.

“The spacecraft is doing remarkably well for something that’s about to vaporize,” a commentator told the crowd. “Our brave little spacecraft is in a very hostile environment.”

The collision occurred just before midnight, with the comet and the impactor craft closing in on each other at a speed of 23,000 mph. The size of the resulting crater depended on the make-up of the comet, but was expected to be the size of a football field and, perhaps, 140 feet deep, officials said.

The Ball crowd was briefly frustrated as they watched the crew at the Jet Propulsion Laboratory react to the pictures of the impact, before they could see those pictures themselves.
When the photograph of the impact — with its bright glow in a cloud of dust — finally appeared on the screen, the cheers and applause were even louder than they had been a few minutes earlier.

“That image says it all. We hit it exactly where we wanted to,” the commentator said.

Engineers from Ball Aerospace developed all the hardware, except the launch vehicle, for the mission.

With the University of Maryland and the Jet Propulsion Laboratory, the engineers designed a two-vehicle system: an 830-pound, 39-inch wide copper impactor that could navigate on its own to crash into the proper place on the comet; and a flyby machine that could record the impact and gather data from the comet afterward.

Alice Phinney, the lead mechanical engineer on the impactor, was overwhelmed after observing the impact.

“I can’t believe we hit this,” Phinney said. “It was absolutely sheer … stupendous, happy, elated, every single emotion.”

For two years, ending in March 2002, Phinney worked on the impactor. The most challenging aspect was minimizing the non-copper components, so a true sample of the elements in the comet could be determined, she said.

Phinney’s husband, Charlie Schira, was in California for the collision. Also an engineer, Schira’s job was to ensure any trajectory changes made would help the impactor hit the comet, Phinney said.

Comet Tempel 1 is named for its founder, Wilhelm Tempel, who discovered it in 1867. The comet circles the sun about every 51/2 years,

The $330 million Deep Impact mission began about five years ago, and the system launched about six months ago. The two parts of the spacecraft traveled together until 24 hours before impact, when the impactor separated and headed toward the comet.

The flyby craft remained behind, staying about 300 miles away to monitor the crash. The impactor was expected to vaporize during the crash.

The flyby spacecraft includes three telescopes, three cameras and a spectrometer for analyzing the interior of the comet that were designed and made at Ball.

“The last 24 hours of the impactor’s life should provide the most spectacular data in the history of cometary science,” Dr. Michael A’Hearn of the University of Maryland said in a news release. A’Hearn is the project’s principal investigator.

“With the information we receive after the impact, it will be a whole new ballgame. We know so little about the structure of cometary nuclei that almost every moment we expect to learn something new.”


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