Io
Hot plumes Thornhill: I predict that when seen close up the temperature of those hot spots will approach that of the Sun as they are both electric arcs. (Electric arcs create intensely hot spots.) see [ 1999 Oct 8]	Result The spacecraft measured the temperatures of Io's "volcanic" hot spots and gave readings, averaged over a pixel, that were hotter than any lava on Earth - in fact, too hot to be measured by Galileo's instruments. see [ 2004 Dec 15]
Channel shapes Thornhill: On the contrary, most of the dark patterns seen radiating from the crater in this image of the Marduk "volcano" are not lava flows. They have the shape of lightning scars on Earth and are caused by powerful currents streaking across the surface to satisfy the arc's hunger for electric charge. They rip huge sinuous furrows in the soil and hurl it to either side to form levee banks and side lobes. The stubby side channels will be found to have rounded ends like those seen on Martian "rivers". see [ 1999 Oct 8]	Result The best resource for this is the closeups of Io's "volcanoes" that show the stubby, round-ended channels. One of the clearest is PIA02545 where you see the scalloped channels off to the right of the so-called "caldera." see [ 2000 May 18]
Moving plumes The plumes are the jets of cathode arcs, and they do not explode from a volcanic vent but move around and erode the periphery of dark areas (called "lava lakes" by planetary geologists) see [ 2004 Dec 15]	Result None of the expected volcanic vents could be found. Rather, the plumes of the "volcanoes" are actually moving across the surface of Io, an exclamation point being provided by the plume of Prometheus which, in the years since Voyager, has moved more than 80 kilometers. see [ 2004 Dec 15]
Cool "lava lakes" Thornhill: The "lava lakes" themselves are merely the solid surface of Io etched electrically by cathode arcs and exposed from beneath the sulfur dioxide "snow" deposited by continuous discharge activity. Therefore, they will not reveal the expected heat of a recent lava flow. see [ 2004 Dec 15]

http://www.thunderbolts.info/predictions.htm#io