The volcanoes on Jupiter's innermost moon, Io, have been extremely active as of late. Io is the most geologically active object in the solar system, due to the gravitational tug-of-war between Jupiter and its outer moons. The resulting tidal forces deform Io, causing intense heat through friction. A similar thing happens to our moon, but without other moons to effect its orbit the effect is much smaller.
One of Jupiter’s moons has unleashed a series of huge volcanic eruptions over a hellish 2 week period that were so bright they could be studied in detail by ground based observatories.