Only certain styles of volcanic activity are suitable, those where detectable thermal emission is from a restricted range of surface temperatures close to the eruption temperature. One method of determining lava eruption temperature is by measuring radiant flux at two or more wavelengths and fitting a blackbody thermal emission function. For Io, it is desirable to determine the temperature of the erupting lavas as this measurement constrains lava composition. The highly variable and unpredictable magnitude of thermal emission from evolving volcanic eruptions creates saturation problems for remote sensing instruments observing eruptions on Earth and on Io, the highly volcanic moon of Jupiter. Future studies of Earth by remote sensing and field observations, and of Io by both ground-based observations and future missions, are needed to answer many questions, including why lava lakes, rare on Earth, appear to be common on Io. Although temporal data for Io's lava lake activity are scarce, studies of temporal variability of lava lakes on Earth are useful for providing ground truth for comparisons. Observations of the largest lava lake on Io, Loki Patera, provide insight into the nature of Ionian lava lakes in general, which may be more similar to eruptive episodes on the East Pacific Rise on Earth, which lead to temporary lava lakes.

We discuss the evidence for active lava lakes on Io and show how modeling based on terrestrial lava lakes can reveal how these phenomena differ on both bodies the superficial similarities do not necessarily imply that the plumbing is similar. Mercury and the Moon do not boast the major calderas or shield volcanoes of their larger rocky neighbors, partly due to a horizontally compressive tectonic regime arising from global contraction that makes it difficult to move melts through the upper crust. We review lava lakes on Earth and other planets, particularly active caldera-like features interpreted to be currently containing active lava lakes on Jupiter's moon Io, and features interpreted as remnants of lava lakes on Venus and Mars. The existence of lava lakes on other planetary bodies may imply similarities in either composition or volcano-tectonic settings, and so has important implications for understanding the link between melt production and volcanism.

Effusion rate at Kanehekili Fluctus dropped by an order of magnitude from ≈95 m3 s−1 in mid-1997 to ≈4 m3 s−1 in late 2001.Īctive lava lakes are rare on Earth, with only ten documented examples, all formed by lavas of basaltic composition and housed inside summit craters or calderas. Kanehekili Fluctus has a thermal emission spectrum that is indicative of the emplacement of lava flows with insulated crusts. It should be a prime target for a future mission to Io in order to obtain data to determine lava eruption temperature. Janus Patera might contain a Pele-like lava lake with an effusion rate (QF) of ≈40–70 m3 s−1. Janus Patera also exhibits relatively steady 5-μm thermal emission (≈20 ± 3 GW μm−1) in the four observations where Janus is resolved from nearby Kanehekili Fluctus.

At Pele, the 5-μm thermal emission as derived from 28 night time observations is remarkably steady at 37 ± 10 GW μm−1, re-affirming previous analyses that suggested that Pele an active, rapidly overturning silicate lava lake. doi:10.1029/2011GL049999), we have examined the variability of thermal emission from three of Io’s volcanoes: Pele, Janus Patera and Kanehekili Fluctus. Using the NIMS Io Thermal Emission Database (NITED), a collection of over 1000 measurements of radiant flux from Io’s volcanoes (Davies, A.G.

Fluctus acquisition