Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: yor_on on 08/05/2013 18:55:14
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http://www.dailygalaxy.com/my_weblog/2013/04/milky-ways-massive-black-hole-an-engine-of-star-creation.html
And then...
http://astronomy.activeboard.com/forum.spark?aBID=58381&p=3&topicID=48519156
27000 ly may give us some little breathing-space I admit, but still?
I will get me a shovel, or maybe a table?
Anyway, it will give us a laboratory for testing GR, at very high energies. "Every galaxy, including the Milky Way, hosts a massive dark object at its core. We only know that they are hyperdense and do not emit light, leading physicists to assume that they are black holes millions of times more massive than our sun. However, there is no direct evidence that these black holes follow the rules of relativity.
"Their measured mass is enough to say that these objects are not neutron stars or clusters of non-luminous objects, but we do not know if the space-time geometry is the one predicted by general relativity," Bambi says."
http://www.newscientist.com/article/mg21829154.700-black-hole-binge-could-test-general-relativity.html
I reckon we can use that energy for a lot of astronomical experiments, testing FTL theories etc. The time-prediction suggested for now seems to be around 2014.
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and my spelling sux.
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Every astronomical body should have the equivalent of a geosynchronous orbit (is there a general term for non Earth bodies?), although gaseous bodies may be more complex as different parts of them may be spinning at different rates.
Anyway, objects inside of the geosynchronous orbit should tend to have a decaying orbit due to gravitational tides. Objects outside of the geosynchronous orbit would tend to be pushed away. The bodies should also have a Roche limit, where an astronomical body would remain intact vs being torn to bits. And, also ignoring atmospheric friction which should be minimal the further one is from the central body.
If a black hole is rotating, perhaps quickly, then it should have gravitational tides that would tend to push stars and other bodies away from it.
This would also indicate that one might expect a galaxy to be slowly expanding (faster rotating gravity near the middle, slower near the edges). And, it would not be surprising for stars to be able to form near the middle, wherever stellar forming material is available.
Perhaps it is more complicated as one might have slower tides due to the outer bodies, and faster tides due to the inner tides, so those stars stuck in the middle may experience some sense of equilibrium, but it should be a shifting equilibrium as outer stars would tend to be pushed away.
I do find it interesting that Galaxies are supposed to be composed of high metallicity, young stars near the middle, and low metallicity, older stars further from the middle. This would indicate that the material where the stars are forming is left over from multiple supernovas, or perhaps even stellar collisions. Anyway, lots of stars have formed in the galactic central disk.
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Sorry, it's not about the milky way making more stars. It's about our galaxy's central Black hole getting a visitor around 2014, celebrating it with some fireworks. It will be a gas.