Are more stars being born or dieing

[ahook12]

I see that a new star is in the Orion Nebula, and this makes me wonder if stars are forming faster than they are being destroyed. Has there been a study done on this are is this obvious. I do not know the answer to this and would love someone to enlighten me.

 

[MeteorWayne]

There's actually a whole bunch of questions in there. Most stars don't "die"; they become a different type of object once the fusion stops. Small ones ( like our sun) become white dwarves, somewhat larger ones explode, but leave behind the core, smaller ones will last many times the current age of the Universe before they go out and slowly fade away. Only the very largest, most massive stars completely explode and are destroyed; but even then, the material is spread across the Universe becoming part of the next generation of stars and planets.

Some galaxies are forming a lot of stars, some have almost completely stopped forming them, but my best understanding would be that since so few stars are actually destroyed, more are forming.

 

[neilsox]

Meteorwyne may be correct on every point. I suspect the question intent was leave leave main sequence instead of destroy. My guess is starbirth is high for the most distant galaxies, because we are seeing them as they were billions of years ago. Likely star birth total mass is decreasing (newer stars are less massive on the average) and total count of star births is decreasing as the the total number of small particles in gas clouds is decreasing, perhaps even the total number of small particles is decreasing for the visible universe. Daily more particles are captured by planets, compact stars ect. Nova, red giants and supernova typical expel less than half of the small particles that were used to make that star long ago. Neil

 

[SpaceTas]

Yes the star forming rate has changed. There was a peak in star formation roughly a couple billion years after the formation of the universe. The star forming history for each galaxy is individual with elliptical galaxies having used-up/lost most of the gas/dust and so are forming has in effect ended. For our galaxy, MW is spot on, and there is plenty of dust/gas to form more stars, and there is a fair amount of recycling. The Sun is a 3rd generation star. But i haven't spotted any study saying weather there is a net gain or loss of stars.

 

[orionrider]

The universe is still quite young (14B years, the same as a Sun-type star lasts). Even the Milky Way is still full of star nurseries, especially in the arms.
Take a look at the neighboring M33 galaxy, it's pink color comes from the regions of intense star formation it harbors.

Many of the smaller stars (smaller than the Sun) burn hydrogen for a longer time than the current age of the universe. So at the moment we don't see any of them leaving the 'main sequence' (die). That alone is enough to account for more star creation than star destruction. Come back in another 5 to 10 billion years and you will see a very different universe.

http://en.wikipedia.org/wiki/Stellar_evolution

 

[ahook12]

Thanks for the excellent posts. I guess the answer to my question is that there are many more stars being born in dust clouds then are turning into white dwarfs, neutron stars or black holes.

There seems to be more small stars and less large stars being formed then in the past, So the expectations is that the process is slowing down and at some point in the future the star formation will slow to a point where dieing stars will exceed newborn stars. That future seems a long way off (many tens of billions of years).

Thanks, Allen