lone star

[kev 102 42]

Are there stars floteing outside a galaxy in outer space...........kev

[toml42]

indeed there are, it would be a lonely existence indeed, i wonder how it would affect the culture and scientific progression of any culture that happened to be orbiting such a star?

whilst i do not believe it has ever been directly observed, as resolving individual stars is next to impossible on all but the closest of galaxies, swathes of stars are likely catapulted into the blackness of intergalactic space when galaxies collide, and this happens relatively often.

there are also several known 'hyper velocity stars' in the milky way in the process of leaving us, it has been hypothesised they were flung out by a black hole.

Milky Way's fastest stars may be immigrants - space - 14 October 2008 - New Scientist

also, stars have also recently been spotted forming in gas jets outside their parent galaxy

NASA - 'Orphan' Stars Found in Long Galaxy Tail

[kev 102 42]

Cheers Tom two great reads, The hypervelocity star 4000km/sec great name......kev

[FraserClarke]

whilst i do not believe it has ever been directly observed, as resolving individual stars is next to impossible on all but the closest of galaxies, swathes of stars are likely catapulted into the blackness of intergalactic space when galaxies collide, and this happens relatively often.

You can detect individual planetary nebulae -- the end states of low mass stars -- between the galaxies in galaxy clusters.

[toml42]

You can detect individual planetary nebulae -- the end states of low mass stars -- between the galaxies in galaxy clusters.

I was not aware of this, do you mean as part of globular clusters?

[FraserClarke]

No, isolated planetary nebula, which of course implies a population of isolated stars. Do a search for 'intra-cluster planetary nebulae' and you should find quite a bit.

The distance modulus to Virgo is ~31 magnitudes, which means giants are 'relatively' easy to detect (~25th mag, say) -- the trouble is distinguishing them from foreground/background objects. PNes give you nice identifiable feature (OIII emission) to allow you to identify them.

They also of course make fantastic test particles to map the mass distribution in the cluster.

[toml42]

ah, wonderful! That's fascinating, thanks

[JamesK]

If these "lone stars" were to collect under gravity, could they die and then could new stars be formed out of the remenants? I mean, given enough time, could a new galaxy build up this way? Obviously as more stars collect it would create a bigger gravity well...

[ollypenrice]

indeed there are, it would be a lonely existence indeed, i wonder how it would affect the culture and scientific progression of any culture that happened to be orbiting such a star?

Great thread. I can't see that being outside a galaxy would have any cultural effect on any intelligent planet dwellers. We have little cultural interaction with our Milky Way neighbours, to put it mildly! But might their astronomers be posting questions like, 'Could

intelligent life arise on planets in galactic systems...?'

Olly

[toml42]

Great thread. I can't see that being outside a galaxy would have any cultural effect on any intelligent planet dwellers. We have little cultural interaction with our Milky Way neighbours, to put it mildly! But might their astronomers be posting questions like, 'Could

intelligent life arise on planets in galactic systems...?'

Olly

The skies would be essentially black, baring any other planets / moons in the system. The night sky has had a massive impact on both our cultural and scientific development, and is a big part of our collected psyche.

Under such conditions, it would seem quite unlikely that other stars would ever be detected. A galaxy or two, sure, but we only realised they were composed of other stars in the last 100 years, and that was after knowing that other stars existed!

I'm reminded of the planet Krikkit in Douglas adams 'Life, the Universe and Everything'

[ollypenrice]

Good point. I hadn't thought through the implications of seeing no stars in the night sky.

Olly

[ncjunk]

But think of the possibility of comets and possibly one galaxy visible to the naked eye, someone would eventually look and then think of all the additional galaxies you could image with no dust in the way.

So you have lone stars ejected into open space, what about other objects burnt out stars or non emiting (in visible light just to keep things simple).

What other lonely travellers might there be?

[ncjunk]

And planets...i forgot planets. They would look spectacular in a black void of sky...and much easier to discover!

[ollypenrice]

And no lack of stellar parallax to confuse an alien Copernicus...

Olly

[Shibby]

Funnily enough this question was in the latest Astronomy magazine. And their answer was also: yes. They state that ALL stars form within galaxies, but some can be thrown out, by several different means.

[dph1nm]

Intergalactic stars in the Virgo cluster have been known about for over a decade:

Detection of intergalactic red-giant-branch stars in the Virgo cluster : Abstract : Nature

NigelM

[Ags]

Wow! I think an observer in such a system would have such black skies that faint fuzzy features like nearby galaxies would stand out. Also the occasional supernova in a nearby galaxy might be visible.

[acey]

Not if they've invented streetlights.