Jupiter, Uranus top UA science blotter

Wildcat File Photo Arizona Daily Wildcat This image shows Jupiter's volcanic moon Io passing above the turbulent clouds of the giant planet on July 24, 1996. This is one of a series of images of Io taken by Hubble to complement the close-up images now being taken by the Galileo spacecraft orbiting Jupiter.

Astronomers worked with the Hubble camera NICMOS to develop vividly colored images of Uranus.

Erich Karkoschka, a University of Arizona lunar and planetary research associate, discovered new details of the four major rings and 10 of the 17 moons that surround the planet.

"The color and brightness will tell us specifics about the surface properties - it may tell us about their origins," Karkoschka said.

The Near Infrared Camera and Multi-Object Spectrometer also took pictures of galaxies never seen before that may be more than 10 billion years old.

"The objects may be the farthest away and oldest that we have ever seen," said Rodger Thompson, a University of Arizona astronomy professor and principal investigator of the NICMOS team.

UA scientists can use the galactic images to decipher the history of the Milky Way and the universe.

"Hopefully we are seeing snapshots of how the Milky Way has formed," said Marcia Rieke, an investigator on the NICMOS team.

Michael Drake, lunar and planetary laboratory director, cited "the astonishing results coming from Jupiter" as one of the most prestigious UA-research activities this year.

An image of Jupiter's moon Io compiled by Paul Geissler, a UA lunar and planetary laboratory senior and research associate, looks more like a disco ball than a celestial body.

Geissler, who assembled the spectacular red, green and blue photo from three of 16 images, never expected to see such brilliant colors.

"It is kind of eerie, unexpected to me," he said. "Io is glimmering away in the darkness - it's spooky."

UA researchers are developing theories to explain Io's glowing green, red and blue spots.

Galileo has also given UA lunar and planetary experts new information about how Jupiter's rings are formed and sustained.

The four small inner moons of Jupiter are bombarded by meteoroids - particles the size of grains of sand - that kick up puffs of dust when they hit the moons. Some of the moon dust drifts out to make up the giant planet's rings.

Jupiter's rings are a fluctuating system, Geissler said.

Over the 4.5 billion years since the planet was formed, there have been periods when the rings entirely disappeared, he said.

There is no predicting how long Jupiter's current rings will remain in existence, Geissler said.

Space gurus continue to demystify the universe as data flows back from myriad instruments.

As Thompson put it, "That's the fun part."

Sarah Spivack can be reached via e-mail at Sarah.Spivack@wildcat.arizona.edu.