Something incredible happened in our own cosmic backyard. The first time scientists have watched the eruption of a distant moon from Earth actually changed its surface. Using a powerful telescope system, they found clear, visible signs of volcanic activity on IO, the wild and fiery moon of Jupiter, an alien world known for being the most active place on volcanoes in the solar system. This breakthrough allows us to witness planetary changes from millions of miles away.
The discovery was made by a team of the large binocular telescope observatory led by Dr. Al Conrad, published in a letter to geophysical research, which reports on new discoveries in Earth and planetary science.
Based on images of the Shark Vis camera mounted on a large binocular telescope, the team captured the most detailed image ever taken from an IO surface – our eyes can see the same light. These photos reveal that part of the famous red ring of volcano Pele has been covered by new deposits. New materials in the image, both bright and dark, may come from strong eruptions from adjacent volcanoes, called Pillan Patera. These observations also help support data collected in thermal sensing studies, called infrared observations, and collected from spacecraft vehicles, which pass briefly through planets or moon during the mission.
What makes this discovery particularly important is that it involves one of the most recognizable and durable volcanic rings on IO. The red ring of PELE is formed from certain types of sulfur that will not last long unless it is constantly replaced by volcanic activity. But in recent images, a large portion of the ring is buried in new frost (a common gas in volcanoes) made of frozen sulfur dioxide and in deeper ash-like material. No such extensive coverage has been observed since the late 1990s.
“These repaved events may be more common than we realize, but early telescopes cannot clearly show them,” explains Dr. Conrad. Photos taken in late 2023 and early 2024 showed that the new bright deposit and its dark center remained the same for weeks. This stable presence suggests that an eruption occurred not long ago and had a great impact.
Dr. Conrad’s team traces the source of the new material to powerful eruptions in mid-2021, discovered through different instruments that measure heat rather than light, which is useful for detecting volcanic activity. That outbreak was described as a huge outbreak, releasing a lot of heat but lasting for a long time. Although it took more than two years to take photos of the area again, images of Shark Vis clearly show how earlier eruptions changed the moon’s surface. Contrary to similar events in the 1990s, when Bailey’s Red Ring recovered within a few years, it seemed to take longer this time, probably because Pele hasn’t had a strong outbreak in recent years.
One possibility that new sediments still exist is that Bailey may not be as active as before, so it does not produce enough material to rebuild the red ring. Older data suggest that Pelley’s heat output or total energy from volcanoes has dropped sharply since early space missions. This decline may explain why the older red material has not returned yet. However, the increase in activity recorded in spring 2023 gives scientists a hint that Bailey may still be able to make a bigger eruption.
The images taken by Shark Vis are sharpened images using a special method to improve detail, called “multi-frame deconvolution”, where several images are combined to show clearer features – allowing researchers to shift the changes on the blob of surface change with a small range. This clarity matches the achievements of early space missions. It also shows how Earth-based tools compete with spacecraft when viewing planetary surfaces. Being able to track these changes on Earth makes it easier to focus on active areas and study how they develop over time.
The discovery of Dr. Conrad and colleagues is an important moment to study the moon and planets of the Earth. They show how using sharpened bright images can help scientists better understand how volcanoes and other surface processes work outside our planet. Thanks to sharks, experts can continue to focus on the ever-changing surface of IO to gain new knowledge about one of the most active places in the solar system.
Journal Reference
Conrad A., Pedichini F., Li Causi G., Antoniucci S., de Pater I., Davies AG et al. “Observe the repavement of IO through plume deposition and use ground-based adaptive optics on visible wavelengths with LBT sharks.” Geophysical Research Letter, 2024. Doi:
About the Author
Dr. Al Conrad In 1994, he received his PhD in Computer Science from the University of California, Santa Cruz. Prior to joining LBT in 2014, he worked as a software engineer and supported astronomers at Lick and Keck Observatories before moving to Max Planck Institute for Linc-Nirvana (LN) to lead the development of the ground AO System (LN). In LBT, AL has always been the point of contact for LN, LBTI and LUCI/AO debugging. His current responsibilities include the Science Archives, Sharks, Sharks, LNs and OSCO. His research interests include asteroid systems and the development of new technologies to study comets, planets and planetary moons, especially Jupiter’s moon IO. He likes to ride a bicycle, sail and dismantle canoe boating.
