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Inferno
2005-Feb-21, 04:03 AM
I know about black holes, pulsars, neturon stars, white dwarfs, etc. But what ultimately happens to stars like our own sun after the reach the white dwarf stage? Do they simply float around space as a hunk of atoms no longer admitting any light? Do they eventually evaporate into nothingness?

crosscountry
2005-Feb-21, 04:14 AM
they just hang out. once it's a white dwarf it has emmited most of the energy it will ever do. It still puts out a little light, but nothing compared to in its younger days and MUCH less than when it sheded its outer layers to make a nebula.

it'll be a dense object orbiting the center of the Galaxy just like it did before. It could possibly collide with another or be put into a new orbit by a close passing, more massive, star - even thrown out of the galaxy.

lots of possiblities.

Inferno
2005-Feb-21, 04:45 AM
I don't why, but I find the idea of all these dead stars floating around the universe kinda creepy.

Maddad
2005-Feb-21, 05:36 AM
http://www.maddad.org/astronomy/
Back in 1999 or so I uploaded several pages on the end life of stars. It needs reorganization, which I'll get around to one of these years. The pages on White Dwarfs and Planetary Nebulae handle the death of low mass stars. The page on Supernovae and Neutron Stars deals with high mass stars.

The information on these pages should be pretty accurate being as it comes in large part from my college astronomy text book. You'll notice page names like 1430.htm and figure numbers like fig1404.jpg because my numbering system at the time followed the textbook chapters. Information for Supernovae and Neutron Stars came from chapter 14.

Argos
2005-Feb-21, 01:40 PM
I don't why, but I find the idea of all these dead stars floating around the universe kinda creepy.

I donīt like the idea of living stars floating around...:) Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.

crosscountry
2005-Feb-22, 05:38 PM
I don't why, but I find the idea of all these dead stars floating around the universe kinda creepy.


do you live near a cemetary? in effect you do. Our star is a second generation star.

There is nothing wrong with deads stars floating around. they just dont' produce light we can detect.

Jorge
2005-Feb-22, 08:04 PM
could a death star be picked up by a much larger star and orbit it?

Argos
2005-Feb-22, 08:39 PM
Almost absolutely no. When they say that space is mostly empty theyīre not kidding... A star will most likely die before colliding (or being picked up) with another one.

Brady Yoon
2005-Feb-22, 11:05 PM
According to current theories of stellar evolution, black dwarfs haven't had time to form yet. White dwarves take a long time to cool since their surface area is so small.

Brady Yoon
2005-Feb-22, 11:07 PM
I donīt like the idea of living stars floating around... Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.


Yup, even when galaxies collide, stars colliding are extremely rare, let alone in a normal galaxy.[/i]

crosscountry
2005-Feb-23, 02:30 AM
I donīt like the idea of living stars floating around... Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.


Yup, even when galaxies collide, stars colliding are extremely rare, let alone in a normal galaxy.[/i]


doesn't that depend on the radial distance from center. probabilities go up by many factors due to the density.

it's still not likely, but more so.

Brady Yoon
2005-Feb-23, 03:33 AM
Yeah I forgot to mention that. You're definitely right.

Argos
2005-Feb-23, 12:35 PM
I donīt like the idea of living stars floating around... Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.


Yup, even when galaxies collide, stars colliding are extremely rare, let alone in a normal galaxy.[/i]


doesn't that depend on the radial distance from center. probabilities go up by many factors due to the density.

Collisions are more likely to happen in young, dense star clusters than at the center of galaxies. Some studies have shown stellar "collisions" in dense star nurseries, though I think calling them "gravitational interactions" instead of "collisions" would be more appropriate. Even in galactic mergers the chances for a collision of stars in their respective centers are slim.

Brady Yoon
2005-Feb-23, 05:08 PM
I donīt like the idea of living stars floating around... Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.


Yup, even when galaxies collide, stars colliding are extremely rare, let alone in a normal galaxy.[/i]


doesn't that depend on the radial distance from center. probabilities go up by many factors due to the density.

Collisions are more likely to happen in young, dense star clusters than at the center of galaxies. Some studies have shown stellar "collisions" in dense star nurseries, though I think calling them "gravitational interactions" instead of "collisions" would be more appropriate. Even in galactic mergers the chances for a collision of stars in their respective centers are slim.

Does that mean stars in newly formed clusters closer together than stars in the very center of the galaxy?

crosscountry
2005-Feb-24, 02:35 AM
I donīt like the idea of living stars floating around... Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.


Yup, even when galaxies collide, stars colliding are extremely rare, let alone in a normal galaxy.[/i]


doesn't that depend on the radial distance from center. probabilities go up by many factors due to the density.

Collisions are more likely to happen in young, dense star clusters than at the center of galaxies. Some studies have shown stellar "collisions" in dense star nurseries, though I think calling them "gravitational interactions" instead of "collisions" would be more appropriate. Even in galactic mergers the chances for a collision of stars in their respective centers are slim.

Does that mean stars in newly formed clusters closer together than stars in the very center of the galaxy?

I think it means they all have the same orbital velocity around the galaxy, and since they are all condensing from the same "location" they are intertwined.

something like "when everything is rotating at the same speed, nothing is rotating".

Argos
2005-Feb-24, 02:44 PM
I donīt like the idea of living stars floating around... Anyway, the chances of a close encounter between 2 stars ("dead" or alive) are virtually zero.


Yup, even when galaxies collide, stars colliding are extremely rare, let alone in a normal galaxy.[/i]


doesn't that depend on the radial distance from center. probabilities go up by many factors due to the density.

Collisions are more likely to happen in young, dense star clusters than at the center of galaxies. Some studies have shown stellar "collisions" in dense star nurseries, though I think calling them "gravitational interactions" instead of "collisions" would be more appropriate. Even in galactic mergers the chances for a collision of stars in their respective centers are slim.

Does that mean stars in newly formed clusters closer together than stars in the very center of the galaxy?

I think it means they all have the same orbital velocity around the galaxy, and since they are all condensing from the same "location" they are intertwined.


Thatīs it! :)