what would happen if two stars touched?

Question

My daughter asked me this question today. She's 9. Something to keep in mind when answering :) I told her I thought they would explode. Then she asked what they would turn into. I said probably smaller pieces of whatever the stars were made of. She thinks maybe black holes, which sounds like a better answer to me. Anyone with better, more technical info, feel free!

Answer 1

I think they will orbit each other (as in a binary (2) star system), usually the larger one starts to tear apart the smaller one, kinda like a black hole.

example of the tearing
http://blog.redshift.de/wp-content/uploads/2006/07/240706-starexplosion.jpg
http://alumni.imsa.edu/~anneka/binaries/fragmentation.gif

if the combined mass is large enough, the star could implode into a black whole I suppose.

(you tube is going down for maintenance within the hour)
here is a video that shows an idea of what happens. the description on the right back up my assumption of a blackhole formation
http://www.youtube.com/watch?v=HfDDI_SCarw&feature=related

oh, chances are they'll maintain their orbit for millions of years if not more



well brant nicely put........

you said she's 9 years old? interesting. where did she pick this idea up from?

Answer 2

I'm not an astronomer but here's what I think. First of all they would touch - if there was enough gravity between them - and then they would merge together. A black hole is caused when the outward forces of the nuclear reaction are no longer sufficient to counter the gravitational forces of the stars mass, so there is a possibility that a black hole would be the result. But depending on the individual masses, it could also just result in a more massive star.

Answer 3

Stars do collide and merge, although very infrequently. When two neutron stars merge, you get a gamma ray burst - huge output of energy, very bright, and you do get a black hole out of it. So good for her! When a regular star and a white dwarf star 'collide' or share atmospheres, you get a supernova explosion, and that's where we get all the heavy elements in the universe from.

However, most stars will never collide, even when galaxies collide. If a star were the size of a basketball and sitting in Boston, the closest star (also about as big as a basketball) would be in New York City. Stars are VERY far apart.

Answer 4

It depends largely on their size. We observe some stars that are called contact binaries. This is where two stars are actually "touching" each other. They orbit each other and if their combined size is not too large, they can continue that way for a long time. Often, a small dense star will pull streams of hot gases off of a larger, cooler companion.

My understanding is that if two white dwarfs contact each other, there will be a supernova-like explosion and then maybe they will condense into one black hole.

Answer 5

If both stars were fusing the same element there would be a sudden, horrific, merging of the two masses, after a very violent, turbulent period a new star would emerge, one with twice the mass, the fusion at the core would increase and the life of the new star would be less than the individual lives of the separate stars if they had not merged.

Answer 6

theyd touch and bam! a big super bright star that you can fly on :o and go with unicorns and gingerbread men :O that run so fast they spin the stars to make fireworks
thats what i would tell my 9 year old kid...

Answer 7

They would probably fuse together, and become an even bigger, (and hence, brighter), star!