We are in fact building a new star as we speak and recreating it much as we created your own lovely Sun 4,575,429,135 years ago based on the success of your civilizations growth and existence beneath it’s light. In approximately 12,322,490,841 (give or take three million years) it should be completed, and well enough developed to hopefully begin to nurture the existence of some neighbors not unlike yourselves.

Unfortunately, by our estimations, your Sun will only be able to support your form of lifeforms for another 4,483,451,937 years. And our company policy is not to interfere with the continued existence of a species unless it is capable of helping itself relocate to another one of the many, many habitable stars we have designed. Perhaps in that time you will have developed enough technologically to survive, and we would encourage you to stop by and bring them some ‘solar warming gifts’ as seems to be an interesting tradition you perform to your own kind when they’ve moved into their new home. However we will have to intervene unfortunately if you cannot sort out the differences between your own kind in that time. We wouldn’t be able to accept a solar sibling rivalry after all, since this could damage our creation. And that would be unacceptable since your civilization is still a long way from having the ability to repay us for the damages.

Live long and prosper humans.

In theory then, it may be possible to, knowing the Sun’s composition in detail, find other stars born with it based on their age and spectroscopic signatures. These stars, although scattered throughout the galaxy, should roughly maintain some elements of their orbit, so we can narrow down where to search somewhat. There are astronomers working on this very problem as we speak!
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Perhaps I’m jumping a few steps ahead, but wouldn’t these also be good candidates for habitable planets? If they formed around the same time as the Sun and have roughly the same composition, it would seem to follow that they’d have the same proportions of rocky planets and gas giants that we have, plus more than enough time for life to form.

Thank you for the picture of the pretty and for reminding me to look up.

I got the information from the Wikipedia pages for all the local stars. It’s entirely possible that Wiki is wrong and/or I misread the numbers – both of which are easily corrected. But if Barnard’s Star and Wolf 359 are indeed geriatric instead of infants, it still backs up my main point which is that our stellar neighbors are mostly not close to the age of Sol and thus wouldn’t have been part of a cluster with it. What I was really trying to understand is whether or not a cluster’s children would disperse over 4.6 billion years, which Woof and Astrofiend answered.

Though now I’m curious about your answer for Sirius – are we certain that A and B formed at the same time? If stars are as mobile as some of the posters here are saying, couldn’t the pup be a captured dwarf that formed in a different place and time? Or at least a Sirius Cybernetics Corporation product gone horribly wrong?

a but over 300 million

Spectroscope, do I detect a New Zealand accent there?

vaccinefree, what you have to realise is that, in many cases, the people/companies promoting anti-vax are trying to do exactly the same as the pharmaceutical companies – sell their products. The big difference (besides the fact that most of the products don’t work!) is that their R & D costs are much smaller.

Trust a real drama queen, vaccinefree is a wannabe drama princess!

I was wondering the same thing. The Centauri system is close to the right age range – about 4.8 billion years old. However, Sirius, Bernard’s Star and Wolf 359 are all toddlers at 100-350 million years old,

I’d like to know where you got those figures from because I’m not sure all are right.

Sirius is definitely a much younger star because being an A1 type Sirian dwarf it is much more massive and thus shorter-lived.* The main-sequence lifespan of A type stars ranges form 300 million for A0 stars to 1.8 billion for A9 stars so Sirius at A1 could be at most a but over 300 million – while our Sun is five billion years old. In fact Sirius is a way into its lifespan given it is accompanied by “the Pup” a white dwarf star.

Now to have evolved into a white dwarf, Sirius B the Pup must have began life as a star much more massive and shorter-lived than the “Dogstar” – but also not quite massive enough to go supernova and thus end life as a neutron star or black hole. So we think Sirius B was originally probably a B3 star with 5 solar masses shining super bright for 101 to 126 million years before becoming the white dwarf it is today.

(See Kaler’s estimate see http://www.astro.uiuc.edu/~kaler/sow/sirius.html)

This means Sirius must indeed be between 130 and 350 million years old. Incidentally, Sirius is sometimes considered to be a possible member of another dispersed cluster – the Ursa Major moving group which includes most of the stars in the eponymous “Big Dipper” – although whether Sirius actually is a member of this group is uncertain & it may well not be.

However, Barnard’s Star and Wolf 359 are, I would think, much older. These stars are dim red dwrafs which began life as more active flare stars such as UV Ceti aka Luyten’s Flare Star & EV Lacertae (the “red dwraf that roared” in a past BA blog thread. See : http://blogs.discovermagazine.com/badastronomy/2008/05/19/the-red-dwarf-that-roared/)

So flaring is an indication of youth in red dwarfs (& stars generally I think) and “stellar toddlers” at the relatively new born ages of 100- 350 million years old – a tiny fraction of the trillion year lifespan of type M red dwrafs – would be expected to show plenty of flare activity and be considered variable flare stars. Yet neither Barnard’s Star nor Wolf 359 show much if any flare activity – just one flare for Barnard’s star that I know of. This stability and their orbits which suggest they are part of the galaxy’s thick disk or even the galactic halo indicates that they may well be much older than our Sun – many billions of years.

Also comparing Proxima Centauri’s flare activity suggests it is younger than them and if Proxima was born at the same time as the other other components of Alpha Centauri then it would be slightly older than our Sun. Thus Barnard’s Star and Wolf 359 would in my estimation be at least seven or eight billion years old if not much older still.

So, please toasterhead, those age estimates have me quite puzzled – could you kindly clear up my confusion here and tell me where you got the figures from & check again that they’re accurate? Because to me they just don’t add up – at least not for the two red dwrafs ?

Lalande 21185 could be as much as 10 billion years old, and Ross 154 is somewhere under 1 billion. So if it formed in a cluster, the sun – or the other stars – would have to have moved really far really quickly. Or can there be a large variation of ages in a cluster?

I would think there may be some variation based on the rate of star formation – some stars forming before others as, for example a wave of star formation moves across a star forming nebula. But I’d also expect all the stars in the cluster to be roughly the same age or within a particular small range of ages.

Oh & I’d also dispute the figure for Ross 154 which once again, I would have thought to be a much more ancient star.

Thanks Bad Astronomer for sharing this spectacular photo and for your always informative & enlightening write up of it! Thanks too IVAN3MAN AT LARGE for your speedy delivery of another superb image! Very much appreciated.

As for #21 Vaccinefree – so you’re getting your asronomy elsewhere but you’re coming here to post about it & say not reading us? What a pratt you are.

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* All stars of the early spectral types O, B, A & F in fact “*must* be younger than our Sun as are all hypergiant, supergiant & bright giant stars. (Ie. luminosity classes 0, Ia, & II.)

7. mike burkhart Says:
October 29th, 2009 at 11:50 am

“I have one question if the sun formed in a star cluster were are the other stars in the cluster? the nearest one to us is 4 light years away unless the distances between stars in clusters is grater than we think ? ”

Consider that the Sun is approximately 4.6 Billion years old. It orbits the centre of our galaxy every 200 million years or so. It has been around the block quite some few times. Also, stars that form together in open clusters are generally all about the same age for reasons I won’t go into.

Now, open clusters like the one our Sun may have been born in are weakly gravitationally bound – they can’t ‘hold on to each other’ for a very long time – maybe a lap or so of the galaxy tops. As such, any stars formed with the Sun will have drifted apart LONG ago – 4.6 billion years is not a short time for this to happen in – it is a veritable eternity.

Does this mean that they are lost forever? Not necessarily. All of the stars formed in an open cluster generally form with the same composition – the same amounts of ‘metals’ (elements heavier than H and He in astronomical parlance). These have the potential to act as a unique identifier or ‘fingerprint’ of the stars from a given cluster. In theory then, it may be possible to, knowing the Sun’s composition in detail, find other stars born with it based on their age and spectroscopic signatures. These stars, although scattered throughout the galaxy, should roughly maintain some elements of their orbit, so we can narrow down where to search somewhat. There are astronomers working on this very problem as we speak!

7. mike burkhart Says:
October 29th, 2009 at 11:50 am

I have one question if the sun formed in a star cluster were are the other stars in the cluster? the nearest one to us is 4 light years away unless the distances between stars in clusters is grater than we think ?

All is ‘splained in the November 2009 Scientific American:
http://www.scientificamerican.com/article.cfm?id=the-long-lost-siblings-of-the-sun

http://www.youtube.com/watch?v=srSbAazoOr8