Loki Patera

[5] Temperature measurements of thermal emission at Loki Patera taken by Voyager 1's Infrared Interferometer Spectrometer and Radiometer (IRIS) instrument were consistent with sulfur volcanism.

Over time, because the solidified lava is denser than the still-molten magma below, this crust can founder, exposing fresh, hot molten rock.

[10] On 8 March 2015 (9 years ago) (2015-03-08), a rare orbital alignment occurred between Io and Europa, two of the moons of Jupiter, that allowed researchers to distinguish heat being emitted from Loki Patera.

They were able to accomplish this because Europa's surface is coated in water ice which reflects small amounts of sunlight at infrared wavelengths.

[11] In December 2023 and February 2024, the Juno spacecraft completed extremely close flybys of Io, including the first closeup images of the northern latitudes, showing the islands within Loki Patera surrounded by a reflective glassy black surface.