NASA released the closest-ever look at Jupiter's moon Io Friday -- a black-and-white photograph that shows lava newly spilled from an erupting volcano.
The image was acquired October 11, Eastern Time, by the spacecraft Galileo as it flew 416 miles (671 kilometers) above the fiery moon, the most volcanic body in the solar system.
Despite glitches that marred the flyby, NASA boasts it was able to acquire the new image (and soon, others), which is 50 times better than the previous best picture of Io, snapped by Voyager 1 in 1979.
The new image shows a lava field associated with the volcano Pillan, which spews lava that is hotter than any currently found on Earth.
The image of the tortured moon is the first of many expected from the flyby, Galileo's 24th since it arrived at Jupiter in December 1995, but its first successful encounter with Io.
The flyby - as has been the case with the mission itself - had its fair share of glitches: Galileo went into protective "safe" mode as it approached Io because of intense radiation. Although some data was lost when Galileo shut down most of its non-essential functions, engineers were able to upload new commands to the spacecraft for its closest approach.
The radiation did cause some degradation to picture quality in some yet-to-be released images, according to the mission team at the Jet Propulsion Laboratory in Pasadena, California.
Most of the Io images were captured in so-called "fast camera" mode, where the camera itself pre-processes the image. Intense radiation threw that process out of sync.
However, other images captured in different modes - including the new image - appear not to have been affected.
"Now that we know this particular camera mode didn't work well amidst the radiation, we'll use other modes from our six different types for the next Io flyby," said Jim Erickson, the mission's project manager.
Radiation also caused a near-infrared mapping spectrometer, designed to study the distribution of materials on Io's surface and the temperature of its volcanoes, to capture only a portion of the spectral data it was designed to record.
Galileo celebrates its 10th anniversary this month. The spacecraft will swing by Io again on November 25, this time passing within 186 miles (300 kilometers) of its volcano-pocked surface.
Because of the extreme gravitational tug of Jupiter, Io's crust flexes with tidal regularity. Like a piece of metal wire repeatedly bent back and forth, the flexing heats the moon, causing its extreme volcanism.
The November 25 flyby will conclude Galileo's two-year extended mission, added to an original two-year visit to Jupiter that ended in December 1997. Mission team members hope NASA will decide to extend the project's lifetime even further, a decision that will likely be made by late January.
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