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It Takes a Cosmic Village to View a Comet [Comet Impact]
NASA ^ | June 29, 2005 | Gay Hill, JPL

Posted on 07/01/2005 7:10:20 AM PDT by Zuben Elgenubi

It Takes a Cosmic Village to View a Comet<


Like people gazing skyward to watch Independence Day fireworks, an international array of telescopes will train expert eyes on a dramatic encounter between NASA's Deep Impact spacecraft and a passing comet. The explosive event will happen 133.6 million kilometers (83 million miles) from Earth in the early hours of July 4 Eastern Daylight Time (late July 3 Pacific Daylight Time). Telescopes on the ground and others orbiting in space will document the mission's crucial moments using different wavelengths of light.

artist's concept showing impactor before colliding with comet Tempel 1

Image right: Artist's concept showing Deep Impact just before impact with comet Tempel 1. Image credit: Maas Digital.

Comets are dirty balls of ice that hold clues to our own solar system's formation and evolution. Deep Impact is the first space mission to attempt to break the surface of a comet and reveal the secrets inside. The mission will send a 360-kilogram (816-pound) impactor into the path of comet Tempel 1. After releasing the impactor, the main spacecraft, called the flyby craft, will move safely aside and collect information. During this phase, every moment counts. The flyby spacecraft will have just over 13 minutes to gather its precious data.

"The flyby craft is constrained to an 800-second interval from the time of impact to the time it will no longer be able to observe the impact site," said Dr. Karen Meech of the University of Hawaii, Honolulu, co-investigator of the Deep Impact Earth-based campaign. "So ground and Earth-orbital observations will be key to realizing the full scientific potential of the mission."

The time chosen for the impact was partially determined by the location of Earth-bound telescopes and their ability to observe the event. On encounter night, telescopes will jump into action like volunteers in a fire brigade, performing specific duties based on their unique abilities.

artist's concept of Spitzer Space Telescope

Image left: Artist's concept of Spitzer Space Telescope. Image credit: NASA/JPL-Caltech.

A trio of NASA's Great Observatories will be watching from orbit: the Hubble Space Telescope with its keen optical vision; the Chandra X-ray Observatory using its powerful X-ray eyes; and the Spitzer Space Telescope with its infrared detectors to measure the heat emitted from the comet at impact. NASA's Galaxy Evolution Explorer and the Canadian and French space agencies' Far Ultraviolet Spectroscopic Explorer will look for specific molecules in the comet. The European Space Agency's Rosetta spacecraft will watch in multiple wavelengths from a different side of the Sun than the other space telescopes. Rosetta is en route to comet Churymov-Gerasimenko and will be the closest telescope to Tempel 1.

On the ground, at least 60 observatories in 20 countries will focus their attention on the bold encounter. Telescopes on Mauna Kea in Hawaii -- in particular some of the world’s largest telescopes, the W.M. Keck , Subaru and Gemini North telescopes -- have teamed up to maximize the unique capabilities of each facility. Radio telescopes, including the Institut de Radio Astronomie Millimétrique telescope in Spain, the James Clerk Maxwell Telescope on Mauna Kea, and Kitt Peak telescope in Arizona, will observe molecules in the comet that vibrate at radio frequencies, in particular the breakdown products of water. Water is probably the most abundant molecule in comets. Prior to Deep Impact's launch, Spitzer and Hubble came up with the best estimates of the comet's size, shape, reflectivity and rotation rate, to help the impactor zero in on its target.

Gemini North Observatory

Image right: Gemini North Observatory atop Mauna Kea in Hawaii. Image credit: Gemini North Observatory.

''The combination of Hubble and Spitzer observations provided scientists with knowledge of the nucleus' shape, size, and shininess, information that we could not get from many years of observing from the ground," said Dr. Carey Lisse of Johns Hopkins University's Applied Physics Laboratory, Laurel, Md. Lisse is team leader for the Spitzer and Chandra studies of the comet event.

Meech and Lisse will be stationed at a NASA facility on Mauna Kea on the night of the impact to coordinate the massive observing effort. They will ensure that mission-critical observations are made and communicated to the Deep Impact science team at NASA's Jet Propulsion Laboratory in Pasadena, Calif. A video teleconference will link all the major facilities around the world.

While only part of the world will have a view of the comet through telescopes at the time of impact, astronomers all over the globe will be able to see the resulting effects over the next several hours, days, and possibly weeks. Some of the observations from professional observers will be posted on the Deep Impact mission site at , and amateur observers are also asked to submit observations at .

"The level of cooperation among planetary colleagues as well as from colleagues outside the field is unprecedented," said Meech. "The experiment has not only engaged people's curiosity, but also a desire to help the Deep Impact mission make the most of its one-shot opportunity."

This fourth of July, a cosmic village of telescopes will make history as they watch the spectacular feat, while the rest of the world waits eagerly for information and pictures.

Gay Hill (818) 354-0344
Jet Propulsion Laboratory, Pasadena, Calif.

TOPICS: Front Page News; Government; News/Current Events
KEYWORDS: comet; impact; tempel
Encounter Timeline.

Also check Deep Impact Homepage and check out "Helpful links". There are some good animations there.

1 posted on 07/01/2005 7:10:25 AM PDT by Zuben Elgenubi
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To: Zuben Elgenubi

It looks like the impact site will be viewable at impact time only on the West Coast.


2 posted on 07/01/2005 7:14:50 AM PDT by Dominick ("Freedom consists not in doing what we like, but in having the right to do what we ought." - JP II)
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To: Dominick
Sky and Telescope has good information too. Watching Comet Tempel 1 — and Deep Impact

Here's a hemispherical map and your location looks pretty close. Of course, poor visibility towards the horizon where you're at.

3 posted on 07/01/2005 7:27:41 AM PDT by Zuben Elgenubi
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To: Hot Tabasco; Dog Gone; eccentric; nuconvert; LasVegasMac; Larry Lucido; sushiman; Ladysmith; ...

Comet impact Ping (this weekend)

4 posted on 07/01/2005 7:37:46 AM PDT by Zuben Elgenubi
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To: Zuben Elgenubi

Thanks for the ping

5 posted on 07/01/2005 7:41:58 AM PDT by nuconvert (No More Axis of Evil by Christmas ! TLR) [there's a lot of bad people in the pistachio business])
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To: nuconvert
At 1:52 a.m. Eastern Daylight Time on July 4, a washing machine-size "impact module" launched from a U.S. spacecraft will slam into the comet Tempel 1 at a relative speed of about 23,000 miles per hour. Astronomers in charge of the mission, dubbed Deep Impact, say the resulting explosion will give them their first glimpse into a comet's icy interior, and possibly reveal important clues as to how the planets formed 4.6 billion years ago. Tempel 1, which is about nine miles long and three miles wide, orbits the sun every 5½ years.

6 posted on 07/01/2005 7:50:07 AM PDT by Zuben Elgenubi
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To: Zuben Elgenubi

I am going to be at a dark site, in the Ocala National Forest that night, however, Spica sets at about 0140 EDT 4 July, and observation is going to be right ON the horizon. It will be due west, over the dark part of the forest.

I won't be able to see it except on TV. I will bring a scope or two out though.

7 posted on 07/01/2005 7:55:41 AM PDT by Dominick ("Freedom consists not in doing what we like, but in having the right to do what we ought." - JP II)
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To: Zuben Elgenubi
Thank you for the ping!

More fireworks!


8 posted on 07/01/2005 7:55:42 AM PDT by LasVegasMac ("God. Guts. Guns. I don't call 911." (bumper sticker))
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To: Zuben Elgenubi; Howlin

There will be a live thread on Sunday. Keep an eye out for it.

9 posted on 07/01/2005 8:31:48 AM PDT by RightWhale (withdraw from the 1967 UN Outer Space Treaty)
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To: Zuben Elgenubi

Thanks for the ping!

It will be setting as the event happens where I will be. I look forward to photos!

10 posted on 07/01/2005 10:39:45 AM PDT by Conan the Librarian (The Best in Life is to crush my enemies, see them driven before me, and the Dewey Decimal System)
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To: Zuben Elgenubi
During its final moments, the impactor will take the closet images of comet's surface ever. The kinetic energy that will be released by the collision is estimated to be the equivalent of nearly 5 tons of TNT. However, this will only change the comet's velocity by about 0.0001 millimeters per second (0.014 inches per hour). The collision will not appreciably modify the orbital path of Tempel 1, which poses no threat to Earth now or in the foreseeable future.

Uh huh.... sure.

Until Marvin gets REALLY ticked about his vacation cottage being obliterated and comes a'hunting!

11 posted on 07/01/2005 10:48:06 AM PDT by Elsie (Heck is where people, who don't believe in Gosh, think they are not going....)
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To: Elsie

LOL, vacation cottage indeed. Good one.

12 posted on 07/01/2005 12:35:16 PM PDT by Zuben Elgenubi (Watch comet Tempel 1 get hit this weekend. Live Thread at FR)
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To: Zuben Elgenubi
Ominous warnings From

Scientists have discovered that comets are natural sources of antimatter. The announcement was made at April 2002 joint meeting of American Physical Society and American Astronomical Society. ... On July 4, 2005, NASA plans to collide a 350 kilogram spacecraft into the antimatter Comet Tempel 1. The spacecraft's impact with the comet will result in a 15,000 Megatons explosion that will fracture the 125 billion metric ton comet into millions of fragments. The antimatter fragments will disperse into solar orbit and periodically collide with earth for years to come. The antimatter collisions with earth will produce tremendous explosions (equivalent to millions of Megatons of TNT), and will destroy life as we know it. Armageddon will have come. NASA should notify the public of their plans to avoid colliding the spacecraft with the Comet Tempel 1. NASA should also inform the public about the opportunities to use antimatter to benefit humanity and turn the Star Trek Dream into Reality.

(it's amazing what valuable information is on the net, yet nobody really believes it...)

13 posted on 07/03/2005 5:08:39 PM PDT by Cvengr (<;^))
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To: Cvengr


It's Tra-la-la-BOOM-dee-yea Time, USA


14 posted on 07/03/2005 11:07:02 PM PDT by ALOHA RONNIE ("ALOHA RONNIE" Guyer/Veteran-"WE WERE SOLDIERS" Battle of IA DRANG-1965
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