. 24/7 Space News .
Galileo Flirts With Amalthea But Zapped By Jupiter On The Final Pass

SPACER
Pasadena - Nov 12, 2002
NASA's long-lived Galileo spacecraft achieved partial success in a dash through Jupiter's inner radiation belts and past the small moon Amalthea on Nov 4, its final flyby before a deliberate impact into Jupiter next September.

This was Galileo's last flyby, after 37 other close encounters with various planets, asteroids and Jupiter's four large moons since launch 13 years ago.

As the orbiter headed closer to Jupiter than it had ever ventured before, it gathered measurements of the energy fields and charged particles in the inner region of Jupiter's magnetic environment. It also examined dust grains that form a "gossamer" ring around the planet.

However, Galileo placed itself in a standby precautionary mode after its closest approach to Amalthea.

It flew past Amalthea at a targeted altitude of 160 kilometers (99 miles) at 06:19 Tuesday, Universal Time (10:19 p.m. Nov. 4, Pacific time), then went into "safe" mode about 30 minutes later. In that mode, onboard fault- protection software suspends many operations until receiving further instructions from the ground.

"We knew this would be a challenging encounter for Galileo, so we are not surprised to have some things go awry," said Dr. Eilene Theilig, Galileo project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Not only was the spacecraft going through a region with more intense radiation than it had ever experienced before, but it was also doing this after it had already survived four times the cumulative radiation dosage it was designed to take and had already operated nearly five years past its original mission."

The flight team at JPL is working on recovery operations, diagnosing what happened and preparing new commands to Galileo that will restore the orbiter to normal and enable the playback of scientific data stored on the spacecraft's tape recorder. Two tape tracks of science data were recorded during the encounter period, out of four tracks planned. Also, the intended type of two-way radio link with Earth for the period closest to the flyby was not achieved.

Now receding again from Jupiter, the spacecraft left the region of radiation danger about 11 hours after passing Amalthea.

Amalthea orbits about halfway between Jupiter and Io, the innermost of the planet's four large moons. Amalthea is an elongated body, about 270 kilometers (168 miles) long.

Galileo has nearly depleted its supply of the propellant needed for pointing its antenna toward Earth and controlling its flight path. While still controllable, it has been put on a course for impact into Jupiter. That's so there will be no risk of it drifting to an unwanted impact with the moon Europa, where Galileo discovered evidence of a subsurface ocean that is of interest as a possible habitat for extraterrestrial life.

Sixty-four minutes after speeding over Amalthea's cratered surface, Galileo passed within about 71,400 kilometers (44,366 miles) of Jupiter's cloud tops. That marked the beginning of Galileo's final orbit, which will end with a plunge into the crushing pressure of Jupiter's atmosphere on Sept. 21, 2003.

Going into a standby mode does not jeopardize Galileo's disposal at Jupiter. No further commanding of the spacecraft is necessary to assure that it is on an impact trajectory, Theilig said.

Related Links
Galileo
SpaceDaily
Search SpaceDaily
Subscribe To SpaceDaily Express

Music Out Of This World
Pasadena - Oct 28, 2002
With scientific instruments on NASA's Voyagers, Galileo, Cassini and more than two dozen other spacecraft, University of Iowa physicist Dr. Don Gurnett has been recording waves that course through the thin, electrically charged gas pervading the near-vacuum of outer space.

NASA'S Stardust Comet-Chaser Passes Asteroid Test
Pasadena (JPL) Nov 06, 2002
All systems on NASA's Stardust spacecraft performed successfully when tested in a flyby of asteroid Annefrank on Friday, heightening anticipation for Stardust's encounter with its primary target, comet Wild 2, 14 months from now.



Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only














The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.