The other day, in the TPBM thread, knowmad and I had the following exchange:
catinthefunnyhat wrote:TPBM thinks it would be cool if there was a planet that was water all the way through... just a big ol' drop of water with ice or whatever it would be at the core, liquid at the surface, and a vapour atmosphere.
knowmad wrote:Whoa! Cool! We were talking about this last night!
I have enjoyed imagining such a planet for years, and wondered whether it would be possible. What would be in the middle? Water under extreme heat and pressure, so... hot ice? Viscous steam? I had poked around on the Interwebs a bit and never found anything. I considered the possibility that such a planet maybe couldn't exist, because the super-heated/pressurized water at the centre might just explode, or something.
Anyways, after the above exchange, I decided to Google it again, just in case things had changed. And lo, what to my wondering eyes did appear, but a press release from Nasa this year!
News Release Number: STScI-2012-13 | February 21, 2012 09:00 AM (EST)
[....] Larger than Earth but smaller than Uranus, GJ1214b has a lot more water and a lot less solid material than our home planet. According to their research, this waterworld is entirely covered with an ocean. Even its atmosphere is a thick steam layer. Not just hazy, but a "dense atmosphere of water vapor."
According to Berta, what's happening in this new type of world is something that we can't imagine: "the high temperatures and high pressures would form exotic materials like 'hot ice' or 'superfluid water,' substances that are completely alien to our everyday experience."
http://hubblesite.org/newscenter/archiv ... 2/13/full/Shorter version from Gizmodo here:
http://gizmodo.com/5887003/hubble-disco ... e-of-waterLarger than Earth but smaller than Uranus

If you want drama to stop following you everywhere, try letting go of the leash.