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Mission Operations Awaiting Contact from CONTOUR Spacecraft
NASA Press Release ^ | August 15, 2002 -- 1 p.m. (EDT)

Posted on 08/15/2002 12:26:09 PM PDT by crypt2k

Mission operators are looking for a signal from CONTOUR, several hours after a scheduled maneuver to send the spacecraft from Earth's orbit onto a path to encounter multiple comets.

CONTOUR's STAR 30 solid-propellant rocket motor was programmed to ignite at 4:49 a.m. EDT and deliver 1,920 meter-per-second boost which CONTOUR needed to escape Earth's orbit. At about 140 miles (225 kilometers) above the Indian Ocean, the spacecraft was too low for NASA's Deep Space Network (DSN) antennas to track it at the scheduled time of the burn.

The CONTOUR mission operations team at the Johns Hopkins University Applied Physics Laboratory expected to regain contact at approximately 5:35 a.m. EDT to confirm the burn, but the DSN has not acquired a signal.

The mission operations team is working through several backup plans to establish contact with the spacecraft, searching along the predicted trajectories for a successful burn.

CONTOUR, a Discovery-class mission to explore the nucleus of comets, was built and managed by the Johns Hopkins University Applied Physics Laboratory, Laurel, Md., for NASA.


TOPICS: Culture/Society; News/Current Events
KEYWORDS: goliath; space
No monitoring during a critical event?
1 posted on 08/15/2002 12:26:09 PM PDT by crypt2k
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To: Cincinnatus; RightWhale; Physicist
bump
2 posted on 08/15/2002 12:27:28 PM PDT by crypt2k
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To: crypt2k
Of course they're monitoring it. Something has obviously gone wrong.
3 posted on 08/15/2002 12:36:09 PM PDT by lainie
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To: crypt2k

4 posted on 08/15/2002 12:37:39 PM PDT by New Horizon
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To: New Horizon
Quite possible - that's what happened to the Russian Mars 96 probe - it's top stage fired in the wrong direction.
5 posted on 08/15/2002 12:39:14 PM PDT by crypt2k
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To: lainie
I guess the hope is it's gone into safe mode.
6 posted on 08/15/2002 12:41:02 PM PDT by crypt2k
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To: crypt2k
On some spacecraft, the antenna only has a limited range of movement. It might not be possible to point it towards earth when you point the engine where you want to point it. Once it is coasting, you can turn the spacecraft so the antenna points at earth again.

However, it is now way overdue.

7 posted on 08/15/2002 12:42:09 PM PDT by KarlInOhio
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To: crypt2k
I am sure it something simple like forgetting to register with Microsoft. They only get 25 contacts before it shuts down.
8 posted on 08/15/2002 12:43:13 PM PDT by phalynx
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To: KarlInOhio
There is a low-gain antenna at the end of the spacecraft opposite the engine, I'd bet if there had been a ship or plane in the Indian Ocean equiped with the proper receiver it could have been tracked.
9 posted on 08/15/2002 12:48:55 PM PDT by crypt2k
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To: crypt2k
Mr. Scott, I need more power!
10 posted on 08/15/2002 12:52:11 PM PDT by colorado tanker
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To: crypt2k
This is not good. The mission would further the information base for dealing with asteroids and comets both for potential earth colliders and for asteroid mining. APL has been doing very well with their spacecraft.
11 posted on 08/15/2002 12:52:19 PM PDT by RightWhale
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To: *Space
Index Bump
12 posted on 08/15/2002 12:53:42 PM PDT by Free the USA
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To: RightWhale
It's for certain NORAD is tracking this - unless it's in too many small pieces.
13 posted on 08/15/2002 2:14:33 PM PDT by crypt2k
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To: crypt2k

CONTOUR                 
1 27457U 02034A   02218.70833333  .00000000  00000-0  00000-0 0   145
2 27457  30.5521 190.6101 8915936 340.4630 356.7346  0.57921679    02
Fifth field in line #2 is eccentricity, decimal point assumed. If it's 0.8916, spacecraft is still in Earth orbit.
14 posted on 08/15/2002 2:28:38 PM PDT by crypt2k
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To: RightWhale
bump
15 posted on 08/15/2002 2:30:59 PM PDT by crypt2k
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To: All
Here are the pre-burn orbit parameters:

The initial parameters of the geocentric phase are period 2,482 min, apogee 108,498 km, perigee 183 km, and inclination 30.2 deg.

16 posted on 08/15/2002 2:37:21 PM PDT by crypt2k
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To: crypt2k
It was already in a highly eccentric orbit. The burn at perigee would have kicked it out of earth orbit and sent it on its way. An explosion, or something came loose inside would be my guess.
17 posted on 08/15/2002 2:42:08 PM PDT by RightWhale
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To: RightWhale
An explosion, or something came loose inside would be my guess.

NORAD should be able to track pieces along the intended path, and verify Contour is not where it should be.

For sure we'll know in a few hours.

18 posted on 08/15/2002 2:44:29 PM PDT by crypt2k
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To: RightWhale

UPDATE

August 15, 2002 -- 7:30 p.m. (EDT)

CONTOUR Contact Attempts Continue

Mission operators continue to scan the skies for the CONTOUR spacecraft, working through a list of strategies for re-establishing contact with the solar-powered probe through NASA's Deep Space Network (DSN).

"We're still trying to get a telemetry link," says CONTOUR Mission Director Dr. Robert Farquhar, of the Johns Hopkins University Applied Physics Laboratory, Laurel, Md. "We're trying to send commands to spacecraft to switch between its two transmitters and use different on-board antennas, in case they turned off for some reason. But we really won't know what happened until we contact it."

CONTOUR's STAR 30 solid-propellant rocket motor was programmed to ignite at 4:49 a.m. EDT and deliver a 1,920 meter-per-second boost that would send CONTOUR out of Earth's orbit and onto a path that would eventually take it past two comets. At about 140 miles (225 kilometers) above the Indian Ocean, the spacecraft was too low for DSN antennas to track it at the scheduled time of the burn. NASA's Jet Propulsion Laboratory, Pasadena, Calif, operates the DSN.

The CONTOUR mission operations team at the Johns Hopkins University Applied Physics Laboratory expected to regain contact at approximately 5:35 a.m. EDT to confirm the burn. When no signal was received, the team immediately began working through backup plans to re-establish contact, searching along the predicted trajectories for a successful burn.

"We're looking at the nominal path, as if the burn occurred," Farquhar says. "We're working on the assumption that the motor fired, and the team is putting its priority there."

CONTOUR's on-board computer is also carrying a command that, about 24 hours after the scheduled burn time, would turn the craft about 40 degrees and perhaps improve its antennas' fix on Earth. Farquhar adds that without knowing CONTOUR's status, it is difficult to know what commands it can, or did, execute. Still, he says, "we're cautiously optimistic that we will find the spacecraft."

CONTOUR, a Discovery-class mission to explore the nucleus of comets, was built and managed by the John Hopkins Laboratory Applied Physics Laboratory, Laurel, Md., for NASA. Additional information about CONTOUR is available on the Internet at: http://www.contour2002.org.

19 posted on 08/15/2002 4:51:02 PM PDT by crypt2k
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To: crypt2k; RightWhale
Still no trace - where's the NORAD data?
20 posted on 08/16/2002 7:09:52 AM PDT by Fitzcarraldo
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