September 11, 2013
NASA Frustrated With Computer Malfunction On Deep Impact Probe
Brett Smith for redOrbit.com - Your Universe Online
As you probably know from personal experience, computer-related problems can be some of the most frustrating to deal with. So imagine the frustration over at NASA, where scientists are having problems with the computer on the space agency’s Deep Impact probe – currently adrift millions of miles away from Earth.NASA scientists announced on Tuesday that they haven’t had contact with the deep-space probe since August 8 of this year.
According to mission controllers, an abnormality generated by the spacecraft's software may have pushed the on-board computers into a state where they are perpetually rebooting themselves. If the NASA team’s suspicions are correct, the on-board computers would not be capable of commanding the probe’s thrusters to fire and hold a correct attitude. A lack of correct attitude would make attempts to reconnect with the craft more difficult because the orientation of its antennas is unknown. An improper attitude would also compromise the vehicle's electrical power status, since the spacecraft generates power from a solar panel array that is in a set position.
Deep Impact’s principal investig will no longer be capable of being revived.
If the probe is lost to space, one casualty would be the images it was supposed to capture in August of Comet ISON. The comet was expected to be highly visible in the sky this fall before diving into the Sun and annihilating itself, but recent analysis of the comet suggests that it may actuall fizzle out even before we get a chance to witness it.
Deep Impact’s initial mission after being launched in January 2005 was to rendezvous with Comet Tempel 1. Seven months after launch, the spacecraft successfully fired an impactor that smashed into Tempel 1, allowing NASA scientists to gather data on the icy object's composition.
In November 2010, Deep Impact flew by Comet Hartley 2 in an extended mission that NASA called EPOXI; a combination of the names Extrasolar Planet Observation and Characterization and Deep Impact Extended Investigation. The flyby was a culmination of a two-year course change that brought the probe within 430 miles of the comet. Deep Impact’s medium-resolution instrument captured photographs of the comet’s peanut-shaped nucleus and several bright jets of material.
The craft observed Comet Garradd from February to April of this year. This time, the probe’s medium-resolution instrument showed that the outgassing from the comet varies over a period of just over 10 hours, which is thought to be due to the rotation of its nucleus.
Before going dark, Deep Impact was able to capture a few distant images of Comet ISON in January. ISON is scheduled to glide just under 730,000 miles above the sun’s surface on Nov. 28. If the comet doesn't disintegrate beforehand, it is expected to put on a stunning skywatching show in late autumn, experts said. The comet was dubbed “ISON” as a reference to the Russia-based International Scientific Optical Network (ISON) that first identified it in 2012.