Actually, the disk around a young star could survive so long as the supernova is more than a light year or so away. In fact, there is evidence that a supernova occured very year our solar system while it was forming. This means that our sun probably formed in a cluster, possibly like Orion. See the article from a few years ago:

http://www.space.com/scienceastronomy/061024_sun_sisters.html

In my opinion planetary systems are formed namely in binary systems. Our solar system is no exception to this rule. The role of the second component in it make an underdeveloped Star – the Jupiter, which is formed by special way. Then Jupiter promotes formation of other planets. http://www.thescienceforum.com/viewtopic.php?t=15901&start=0

Is there any clouds nearby that we can’t see? I would suspect that we are outside the cloud that we were originally formed in and in the many years and rotations it’s remnants are probably far far away. Depending on how eccentric our orbit is when we left and what other gravity fields either of us got too close to, it could be closer, further, up meaning closer to one saucer plate, or down meaning closer to the other saucer plate stacked rim to rim, and many other varibles that you probably know much more about and I don’t have the time to list.

How did “Lost” become involved?

I honestly don’t know. Ask Phil. It was he who wrote that. I was just trying to point out to Mr. English teacher Ivan3Man the grammatical validity of the sentence.

Knowing Phil’s proclivity for making pun, it wouldn’t surprise me at all if he was making allusions to Lost.

Hadn’t heard about this – thanks for posting it BA.

@ 8. Metre Says:

@ Stone Age Scientist #6 : True, but I still think the luminance of the nebular material would be low, especially when compared to the brightness of those big stars. The eyes cannot collect light like a camera. You might get hazy patches near a few brighter stars, but I don’t think the whole sky would be bathed in bright, visible, well-defined nebulosity. I could be wrong, but my experience is that nebulas can be made to appear very bright in photographs, but are very hard to see visually (and the bigger they are, the harder they are to see).

I’d second that. The reason we get so many marvellous astrophotos of nebulae I think comes down mainly to two words : Long exposure.

That noted, I have read that the very largest nebulae may still be very impressive. Example : apparently if the Tarantula nebula in the Large Magellanic Cloud (LMC) was located as close as the Orion nebula (M 42) is to us it would be bright enough to cast shadows!

@ 23. Russell : I wonder if there is a star named 867-5309

Probably – if you call that a “name” rather than just a catalogue designation. There’s certainly a (Gliese) 876 which is kind of close … BTW. Gl 876 was one of the first red dwarfs discovered to have exoplanets, the lowest a 7 Earth mass, “Luciferean” or super-Venus / Hot Neptune type world.

@ 27. Keith Harwood :

I don’t think star B would be seen as `an intense red glare’ from star A. If star B is a red dwarf its surface temperature will be more than 3000K. In other words, about the temperature of a tungsten light bulb. Star B would be slightly yellower than star A. (To a human eye, that is.) IIRC, the only stars which really look red are the carbon stars, where the molecular carbon absorbs the blue wavelengths and the spectrum of the star is a long way from black-body. OK, brown dwarfs will also look red, but we are talking about Real stars here. I think Dave Malin wrote a book about this.

Would that book be ‘Colours of the Galaxies’ by David Malin & Paul Murdin (Cambridge Uni. Press, 1984) by any chance?

Carbon stars and red dwarf stars have similar temperatures but, as I understand it, carbon stars have much more carbon in their atmospheres to absorb more blue light making the star appear redder – there are also some rare examples of carbon dwarfs as well.*

@ 19. DrFlimmer :

I think the biggest challenge is the companion star. It is likely that it is up at “night”, so it could be hard to achieve a clear “night” at all on such planets.

Sometimes sure but don’t forget there may be other times when the companion star is up in the daytime instead leaving some nights clear.

Also remember the bright giants, supergiants and O-B type dwarfs all have some pretty impressive absolute magnitudes (intrinsic brightness’s) meaning that from thirty light years away they’ll be as bright or brighter than Venus at its brightest for us or even the crescent Moon. From closer still, well they’ll be very spectacular and able to be seen in the day as well. Rigel for instance has an absolute magnitude of minus seven or eight. So if it’s only a few light-years away and you do the math it may be as bright as the full moon – about minus twelve or so. Perhaps?

Of course, this depends on the exact location of these stars to our binary system … & how much obscuring gas and dust lies in the path of their view.

@ 9. Brent :

I’m amazed we haven’t seen a reference to this being a future home for Tatooine (http://en.wikipedia.org/wiki/Tatooine) yet…I’m guessing because to us the stars appear pretty different to us…or because this isn’t a long time ago, but rather would be in the future and isn’t far far away, but is fairly close by?

There is already an exoplanet nicknamed “Tatooine” that orbits in a triple star system found some years ago now :

“HD 188753 b or “Tatooine” : The first exoplanet found in a system with three stars. It orbits a G9 dwarf in 3.3 days with an orange dwarf binary beyond in an elliptical orbit ranging from 6 to 19 AU. The system lies 145 ly off in Cygnus. ”

(From my personal exoplanet listings compiled from various sources.)

* See “NewsNotes – Dwarf Carbon Stars” , P. 22 ‘Sky & Telescope’ February 2003.

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PS. Why is this post being held for moderation? Odd. No links in it or nothing. I’m curious about this & wondering what if anything I’ve done wrong? Is it too long or too many quotes or … what?

life there could visit the other system!

Heh! I never imagined that the stupid creationist hypothesis of a privileged planet would so soon be torpedoed by facts. [envious] And if we find these close neighbor systems so early on, moving from observing exoplanets to observing exoplanet systems as Jeff notes, they will likely be common. [/envious]

Life seems to require a quite eclectic combination of metals to grow.

So it would seem, but also it seems that every time they find a protein with a specific characteristic they find a variant or a loss. Photosensitive systems have been found using several metals, oxygenating systems likewise or a total loss such as that cold sea fish they found that have no oxygen carrying blood cells at all.

My newest favorite example is prions, I read recently that these proteins are found to have a large part that is “amorphous”, non-rigid, which perhaps is connected to their ability switch to an infective form. Maybe they aren’t the first such proteins found, but if true it seems to me they break the idea that proteins have to find definitive characteristic foldings (and sometimes alternate ones).

At a guess the list of metals used are decided as everything else evolutionary, by contingency.