Posted on 10/24/2018 8:49:46 AM PDT by BenLurkin
Plumes are common throughout the solar system. Jupiter's moon Io is constantly shooting volcanic material into the air. Saturn's icy moon Enceladus famously blasts water vapor and other material from its subsurface ocean into space via a set of geysers near the south pole. And Earth is rich in geysers, from Yellowstone National Park's Old Faithful to Iceland's Great Geysir.
Firing off the gas that makes up these plumes requires an energy source, which usually heats up the ground around the plume source. Enceladus, Io and Earth all have hotspots around their geysers and volcanoes.
But not Europa, as far as we can tell. Rathbun and her colleagues saw no hotspots at either of the purported plume locations described in the Galileo data.
There are four possible reasons for this result, Rathbun said. First, it's possible that the jets don't exist. It's also possible that the hotspots exist but are subtler than could be detected with Galileo or the Earth-based Atacama Millimeter/Submillimeter Array (ALMA).
Another option is that the plumes are sporadic and just didn't fire off while Galileo was nearby. Finally, Europa's plumes may operate differently from the geysers on other worlds.
"Europa was expected to be active," Rathbun said. "Folks have been wondering where [the plumes] are and what happened to them."
(Excerpt) Read more at space.com ...
*ping*
It’s not about options. You can’t choose what explanation you want to use. There is also a possibility that the hotspot is the core of the moon in discussion.
Furthermore what is a hotspot and why is it hot? We have much more observational data than ever before and they keep recycling the old explanations. Maybe they don’t exist. Maybe they are hotspots. Maybe we missed them. Enceladus is a tiny little thing so far away from the sun that the only source of heat is either tidal forces or residual heat from when it was formed. Yet it has hotspots? Europa most likely has a core that is heated somehow and any out gassing is likely to be spread out over a large area with small plumes rather than large spectacular plumes.
“All these worlds are yours, except Europa. Attempt no landing there.”
ah but are there any plumes coming from Uranus?
Trump’s fault!
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
