Comet-chasing Spacecraft Had a Problem

The Comet-tailing spacecraft known as CONTOUR, launched last month, was sorrying NASA scientists, since it hadn't called in on schedule, and seemed to be ignoring signals from Earth.

There's a system aboard, though, that automatically sends an "I'm, OK" message, after 96 hours of radio silence. That message didn't materialize, either.

Californians with a telescope looked where the satellite was supposed to be, and sure enough -- there it was; er, there they were. Since only one object was launched, and two or more appeared on the trajectory, the sighting spelled trouble. CONTOUR has changed shape. It's not supposed to do that.

Whether the bird was hit by space junk, or came apart on its own, we may never know. In any event, this $159 million project's over.

NASA's not so pessimistic. Here's what the Agency says:

Two objects, believed to be spacecraft segments, were detected Aug. 16, the day after the solid rocket motor burn, and a third more distant object has since been found. The objects are now more than 2 million kilometers from Earth, traveling at a steady 6.1 kilometers per second (3.8 miles per second or 13,600 miles per hour). They remain on a trajectory predicted by early observations; although they have now traveled so far from the Sun and Earth that more observations are unlikely.

If the spacecraft is still capable of operating, by Thursday, Aug. 22, it will have completed the first cycle of having each of its two transmitters attempt to send a signal through each of three antennas. Near continuous monitoring for CONTOUR continues through Sunday. After that, efforts will be scaled back to once a week - a schedule that will be maintained until early December when the spacecraft will come into a more favorable angle for receiving a signal from Earth. Deep Space Network coverage will extend through this weekend.

As far as contacting the spacecraft this week, Dr. Robert Farquhar, CONTOUR mission director from the Johns Hopkins Applied Physics Laboratory says, "We known there's not much room for optimism through this week. Even the second week of December, when we have our best shot, chances are small. But it's still worth monitoring."

FMI: www.nasa.gov