Jupiter and Saturn

In another chapter in the vast tome known as Holy Shit, The Universe is Freaking Cool, scientists tell us now that giant gas planets have centers where metallic helium and metal hydrogen mix to form a freaky metal alloy in liquid form.

Some bits from the article:

  • The pressure at the Earth's core? 3.5 million times normal atmospheric pressure. Jupiter's core hits 70 million times normal atmospheric pressure.
  • The cores of Jupiter and Saturn are two to four times hotter than the surface of the sun, which is almost the temperature Arizona reaches in July.
  • The pressure at the cores of these big planets smash helium until it's like liquid mercury only less shiny.

But my absolute favorite is below the break...

This finding also speaks to one of the many mysteries of these large planets, [University College London's Lars] Stixrude said. More energy is emitted from Jupiter and Saturn than they absorb from the sun, and scientists don't understand where it comes from. One of the prevailing theories is that droplets of helium condense out of the planets' outer atmospheres and fall to their centers as "helium rain," releasing gravitational energy. But [UC Berkeley's Raymond] Jeanloz and Stixrude's findings show that helium and hydrogen are probably a more homogenous mix than was previously suspected, meaning that helium rain is unlikely. "Now, we have to look elsewhere for this energy source," Stixrude said.

More energy is emitted from Jupiter and Saturn than they absorb from the sun and helium rain was a possible explanation. My mind can't even wrap itself around the idea completely, but I realize it's cool. Space is full of cool stuff. As an aside, let me share with you my favorite cool space fact: the star Antares is as big around as the Earth's orbit around the sun. When I think of that, I'm reminded of the bit in Greg Bear's Blood Music where a character says, "They're having a bit of a problem with scale."

Speaking of scale, here's too much fucking perspective right here:

Direct link for the feedreaders.

And if that puts you into an interesting headspace, a live performance of "Astronomy Domine" is just the thing to chase it with.