Huge Hydrogen Cloud Will Hit Milky Way 220
diewlasing points us to a story about a hydrogen cloud, eleven thousand light-years long, which will collide with the Milky Way in a devastating crossfire of shock waves and star formation...in 20-40 million years. Mark your calendars. At least it will give us something to watch while we're waiting for Andromeda to hit us in a few billion years. Hopefully, it will look at least this cool.
"The detailed GBT study dramatically changed the astronomers' understanding of the cloud. Its velocity shows that it is falling into the Milky Way, not leaving it, and the new data show that it is plowing up Milky Way gas before it as it falls. 'Its shape, somewhat similar to that of a comet, indicates that it's already hitting gas in our Galaxy's outskirts,' Lockman said. 'It is also feeling a tidal force from the gravity of the Milky Way and may be in the process of being torn apart. Our Galaxy will get a rain of gas from this cloud, then in about 20 to 40 million years, the cloud's core will smash into the Milky Way's plane,' Lockman explained."
I don't think it means what you think it means... (Score:5, Insightful)
Does anyone else have a problem with the word "smashing" to describe the contact of two bits of not-quite-vacuum passing through each other?
Re:I don't think it means what you think it means. (Score:3, Insightful)
Gravitation is an interaction force (Score:5, Insightful)
There are four known forces in the universe, the weak and strong nuclear forces are short-range, while the electrical and gravitational forces are long-range, which means they will produce interactions everywhere in the universe.
Electrical forces come in two polarities, positive charges balance out negative charges, but gravitational forces always add up. There's no known way to block gravitation, therefore one can say that any two galaxies in the universe are "close enough for an interaction force to be produced", given enough time.
In the context of the article, I suppose "smashing" means close enough to produce significant distortion in the overall shape of the hydrogen gas cloud.
Re:The Earth is 6000 years old (Score:3, Insightful)
When they are confronted with it somehow, they either ignore it or pull out some variety of Last Thursdayism: the universe was created with all of the bits already in motion, and the light from distant stars already underway, and the fossils neatly buried. Rationalisations as to the reasons for this range from "test of faith" to "giving us something to look at in the night sky".
Remember: evidence against scientific hypotheses mean the science is wrong, but evidence against the Bible means the evidence is wrong.
Re:I don't think it means what you think it means. (Score:2, Insightful)
Two points:
(1) The sun's outer atmosphere is already in the millions of degrees.
(2) Our planet orbits within the sun's outer atmosphere.
Re:Shot in the Dark (Score:2, Insightful)
Probably not so much. The difference is that the Earth is a rigid object, while the galaxy is a swirling pile of unconnected particles. It would take a very long time for tidal locking to redistribute the energy.
20 million years? (Score:2, Insightful)
I realize there are probably other ways to keep it from hitting our solar system, but I'd like us all to agree right here and now that a black hole cannon is how we are going to deal with this, just so we're all on the same page and can get our act together in time.
Oblig Douglas Adams Tribute (Score:2, Insightful)