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Jupiter Gets New Red Spot
saskboy writes "The planet Jupiter is growing a new red spot. Jupiter is already well known for its Great Red Spot storm which is visible through modest backyard telescopes, so it will be interesting if this newer spot sticks around and grows. From the article: 'The official name of this storm is Oval BA, but Red Jr. might be better. It's about half the size of the famous Great Red Spot and almost exactly the same color. Oval BA first appeared in the year 2000 when three smaller spots collided and merged. A similar merger centuries ago may have created the original Great Red Spot, a storm twice as wide as our planet and at least 300 years old.'"
Err... Saturn is his father.
It was supposed to be "All these worlds are yours except Europa. Attempt no landing there."
That's what I thought until I noticed the story was from yesterday, and it was because the spot had only recently turned RED from white.
Saskboy's blog is good. 9 out of 10 dentists agree.
Raw hydrogen needs to react with something to generate energy. And react it does! You'll almost never find pure hydrogen available except in an environment where it's very hot and breaks down chemicals, or where there's nothing else to combine with (such as the Sun itself). Raw helium reacts with nothing: it's a noble gas, and you can't harvest energy from chemical interactions with it because there are so few that occur. Ice is cold water: the energy available from it was the result of hydrogen combining with oxygen, which released a lot of energy but makes it tough to get any more energy out of it now that it's already turned into water.
Now, there are levels of Jupiter's atmosphere where more complex and useful molecules are likely, due to pressure and lots of available components. Methane, for example, or other useful hydrocarbons that would have some energy to release and could be used for fuel in various interactions should be quite popular at some levels of that very deep atmosphere. And there are some fascinating proposals for how life could eveolve there. But please actually look them up, and maybe take a basic chemistry course to learn about what "using something for energy" means about the chemicals involved.
One of the key differences is temperature. If Titan were placed in Earth orbit the situation would be dramatically different, the atmosphere and probably a good deal of Titan itself would evaporate and be blown away. However out by Saturn way, the mean temperature is what we call in the technical sense cold.
Also, Titan's orbit is filled by a toroidal cloud of hydrogen much of what does escape is reabsorbed by the moon itself. Sky and Telescope had a good article about it a decade or two ago.
A bit of Earth's atmosphere blows out into space as well. Apollo 16 brought back some nice UV photos of the Earth's hydrogen corona, caused by splitting of H20 molecules in the upper atmosphere by UV light. The hydrogen is eventually lost to space but not at a rate that we have to worry about losing our oceans soon... at least not to evaporation.