center of galaxy

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gmlket

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How close are the stars at the center of our galaxy, when you look at other galaxies it seems the densest parts are in the middle. Are these stars at the center light years away from each other?
 
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MeteorWayne

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They are much closer than they are out here in the suburbs. Our closest star is 4.3 light years away. Recently a star came with 17 light hours of the black hole at the Milky Way center. That's REALLY close!

Here's an APOD shing 8 years motion of stars near the MW Center

http://apod.nasa.gov/apod/ap001220.html

Here's a view of the Central 3 light years . All the star you see would fit between us and Proximi Centauri, our closest star.

http://apod.nasa.gov/apod/ap081211.html



MW
 
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xXTheOneRavenXx

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MeteorWayne":1zfkt98l said:
They are much closer than they are out here in the suburbs. Our closest star is 4.3 light years away. Recently a star came with 17 light hours of the black hole at the Milky Way center. That's REALLY close!

Here's an APOD shing 8 years motion of stars near the MW Center

http://apod.nasa.gov/apod/ap001220.html

Was there a couple of planets orbiting 2 stars close to the middle region, or was that just an image glitch? Can planets even exist there?
 
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thnkrx

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Was there a couple of planets orbiting 2 stars close to the middle region, or was that just an image glitch? Can planets even exist there?

Almost certainly an imaging glitch or multiple star system(s). Very very few planets have been directly imaged as yet, and those are close by, astronomically speaking.

As to planets existing there is the first place...yes.

1) Some of the planets found so far are in double star systems (usually wide doubles, with separations on the order of a few hundred to a few thousand au. Even at the core, the separation between stars would still, on average, be at least that much.

2) Many stars orbit the galactic core in highly eccentric oribts which take them from the core region out into what amounts to intergalactic space (space between galaxies). These orbits are typically on the order of hundreds of millions of years, giving planetary systems a chance to form and become stabilized.
 
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dragon04

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But not very hospitable unless living in an operating microwave oven could be considered hospitable.
 
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thnkrx

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But not very hospitable unless living in an operating microwave oven could be considered hospitable.

True...especially for stars whose galactic orbits do not take them out of the core region. However, there are 'hot' and 'not so hot' radiation zones throughout the center third of the galaxy. (Used to be a nifty map you could download showing this). So...if you were to take one of the stars on an eccentric galactic orbit, where it spends only a comparatively small amount of time in the galactic core region, and if that orbit missed the worst of the 'hot' zones...I suppose it would be possible - barely - for that star to have a habitable planet.

Probably have better odds of winning big at Vegas, though.
 
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gmlket

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If there was a earthlike planet near the center of our galaxy, would there be permenant daylight on it?
 
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thnkrx

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If there was a earthlike planet near the center of our galaxy, would there be permenant daylight on it?

First, the radiation surges for a planet on a star with a galactic orbit that keeps it near the core would almost certainly preclude that planet being earthlike. It is just barely possible for a world orbiting a star that has a highly eccentric galactic orbit to pass through the core region to be earthlike.

With that in mind...best example I could think of off hand would be wide space multiple star systems, where the components are several hundred to several thousand astronomical units apart. From the POV of the denizens on an earthlike planet orbiting the one star, the other, more distant component(s) would come across as very bright stars - possibly a couple times brighter than the full moon in our own sky, depending on the spectral type and luminosity of the companion(s).

Given the density in the core region...the 'night side' of such a world would probably be in perpetual 'twilight' - not really bright enough to count as daylight, but not really dark either.

Another issue would be interstellar dust and gas which would interfear with the light coming from neighboring stars; very likely this would be much thicker in the core region than it is in our own corner of the galaxy. If sufficiently dense, this cloud would both dim the light coming from those stars and give them a reddish tint (light extinction).
 
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Boris_Badenov

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This is a Radio image of our Galactic Center created using the VLA. It is another one I have on the wall of my office

GalCent-WideField_lo.jpg
 
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origin

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MeteorWayne":3laex0y1 said:
They are much closer than they are out here in the suburbs. Our closest star is 4.3 light years away. Recently a star came with 17 light hours of the black hole at the Milky Way center. That's REALLY close!

Here's an APOD shing 8 years motion of stars near the MW Center

http://apod.nasa.gov/apod/ap001220.html

Here's a view of the Central 3 light years . All the star you see would fit between us and Proximi Centauri, our closest star.

http://apod.nasa.gov/apod/ap081211.html



MW

Excellent post MeteorWayne! Thank you; it was very illuminating (no pun intended) on the density of the stars in the cernter of the glalaxy. The movement of the stars over 8 years is amazing. That is one of the coolest things I have seen in a while!
 
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