Since 1979, when Jupiter’s moon Io was found to be pockmarked with volcanoes, astronomers and volcanologists have been excited by what the reddish satellite could tell us about the evolution of the Jovian system and Earth’s early volcanic history. Yet, studies of eruptions and lava flows on Io have been hampered by fuzzy images from Earth-bound and space-borne telescopes and far too few closeups from flyby spacecraft.
A sharp new camera recently installed on a telescope in Arizona could remedy that.
A team of astronomers and engineers will publish next week in the journal Geophysical Research Letters the highest resolution optical images of Io ever taken from Earth — images sharp enough to discern volcanoes so close to one another that the debris from their eruptions overlap.
Taken by the Large Binocular Telescope (LBT) on Mount Graham in Arizona, the images were made possible by a new high-contrast optical imaging instrument, dubbed SHARK-VIS, and the telescope’s adaptive optics system, which compensates for the blurring induced by atmospheric turbulence.
The images reveal surface features as small as 50 miles across, a spatial resolution that until now had been achievable only with spacecraft sent to Jupiter, such as the two Voyager spacecraft in 1979, the Galileo mission, which ended in 2003, and Juno, which has been orbiting Jupiter since 2016. The resolution is equivalent to taking a picture of a dime-sized object from 100 miles away, according to the research team. The images are two to three times better than could be obtained through the Hubble Space Telescope.
“The visible light images are really incredible,” said Imke de Pater, a professor emerita of astronomy and of earth and planetary science at the University of California, Berkeley, who helped interpret the images with Ashley Davies, a principal scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California, and Katherine de Kleer, assistant professor at the California Institute of Technology.