Star close to us in milkyway ready to go supernova?

Originally posted by azdude1804
i think ur wrong about the years there buddy. i think i might be getting a little confused. but if it was 425 lightyears away, then it would be, probably thousands of years before we saw it, because 1 lightyear equals 4 earth years. so what ever amount of lightyears u have, quadruple it in earth years.

No, one light year is the same one earth year. They both last one year. A light year is just a unit of measurment of how far light travels during one year.

Originally posted by ChrisRT

Thats not true, your thinking the wrong way round, it would just mean it actually happened 425 years ago and we can only see it starting to blow up now.

That is what I said. Also, it wouldn�t have the same luminance as our Moon...

Ok, after carefully re-reading your post, I believe you got your logic right after all, my mistake. I stand by my statement about the moon, obviously not as big though.

Gazrok, i was always inclined to think there was more 'control' behind that guiding star, but you could be equally right, good point.

Originally posted by azdude1804
i think ur wrong about the years there buddy. i think i might be getting a little confused. but if it was 425 lightyears away, then it would be, probably thousands of years before we saw it, because 1 lightyear equals 4 earth years. so what ever amount of lightyears u have, quadruple it in earth years.

Erm. No.

A lightyear is approximately 5,869,713,600,000 miles (5 trillion eight hundred sixty nine billion seven hundred thirteen million six hundred thousand miles), the distance that light travels (on average) during one earth year.

You can calculate this by taking
186,000 (miles per second, the speed of light)
times 60 (seconds in one minute)
times 60 (minutes in one hour)
times 24 (hours in one day)
times 365.25 (days in one year)

Technically, lightyear as a unit of measurement is frowned upon, but it's easy shorthand for newspaper articles. Saying a star is 425 lightyears away is a lot more digestable than saying it's 2,494,628,280,000,000 miles, or 3,991,405,248,000,000 km away

Originally posted by PanzerDiv
You have to take into account the pure distance! It might have already happened and we havent seen the light from the Supernova yet!

the person who discovered a star that is about to go supernova would have obseverved it at this great distance, so the distance is irrelevant. lets say they predict that it'll go supernova a year from now by observation. If its 2 million light years away it went supernova 1,999,999 years ago, but it will still happen for us a year from now.

Maybe you heard about the star Eta Carinae. Very recently, it was the subject of the APOD.

There may be others actually, but that's all I have at the moment...

``

that supernova you've all been referencing
was that the one in 1066 AD ???

if your really into it
there was a very close (in cosmic neighborhood) Nova
about 2 million years ago
in fact our whole solar system is in a molecular cloud 'tunnel'
or void area blasted out by that super-nova

maybe that GammaRayBurst from that super-Nova affected
our primitive ancestors.......for example the branch of Homo
of which the fossile named "Lucy" is about that old....

maybe the GRB mutated the DNA that eventually led to modern man?

(its difficult to favor one science [anthropology,astronomy] over another as a career choice...?eh)

Originally posted by Croat56
I dont think it would kill us. I think itll just be one hell of a light show. Just to clarify how bright would it be. Will it be like a sun and turn the night into day or just look like a bigger star?

In 1987 was the last supernova that I know of that could be seen without a telescope supernova 1987A. A supernova would be a million times brighter then a normal sun.

Heres a pic of 1987a

This explosion actually took place 170,000 years ago (about the time Cavemen were living on Earth) we just saw it in 1987

www.windows.ucar.edu...=/cool_stuff/tourstars_45.html

[edit on 18-12-2004 by ShadowXIX]

Originally posted by PanzerDiv
I remember a documentry i watched that said if a supernova would occur within 25 lightyears of earth, That the earth would Fry!

The nearest star besides are own is 11 light years away from us (possibly nine?). I sure hope none of them go anytime soon.

Originally posted by faddinglight
The nearest star besides are own is 11 light years away from us (possibly nine?). I sure hope none of them go anytime soon.

Wrong, only ~4 LYs away.

www.astro.wisc.edu...
www.dudeman.net...
www.cosmobrain.com...

Fact that this data could have been found with google simply using words "closest" and "stars" kinda makes me skeptical about future of mankind.

Originally posted by E_T

Originally posted by faddinglight
The nearest star besides are own is 11 light years away from us (possibly nine?). I sure hope none of them go anytime soon.

Wrong, only ~4 LYs away.

www.astro.wisc.edu...
www.dudeman.net...
www.cosmobrain.com...

Fact that this data could have been found with google simply using words "closest" and "stars" kinda makes me skeptical about future of mankind.

yes, this person is right. its called Proxima Centauri

Originally posted by ShadowXIX

Originally posted by Croat56
I dont think it would kill us. I think itll just be one hell of a light show. Just to clarify how bright would it be. Will it be like a sun and turn the night into day or just look like a bigger star?

In 1987 was the last supernova that I know of that could be seen without a telescope supernova 1987A. A supernova would be a million times brighter then a normal sun.

Heres a pic of 1987a

This explosion actually took place 170,000 years ago (about the time Cavemen were living on Earth) we just saw it in 1987

www.windows.ucar.edu...=/cool_stuff/tourstars_45.html

[edit on 18-12-2004 by ShadowXIX]

yes, it would be millions of time brighter than a sun, but by the time it gets to us, it wont be.

Well it all depends on how far away it is If that one 4 light years away goes we might be in for a world of hurt 4 years after it happens.

Originally posted by ShadowXIX
Well it all depends on how far away it is

If that one 4 light years away goes we might be in for a world of hurt 4 years after it happens.

Maybe not as soon as 4 years later (see my last link), but it is certain that we would be in great problems... See a few of supernova remant sizes (10 light-years, 30 l-y, 60 l-y,...) in a few nice links from APOD:

Cassiopea A
Tycho's Supernova remnant
N49
N63
Crab nebula

Do a search in APOD for "supernova remnants" and you'll find a lot more of interesting stuff.

[Edit:]
Don't go and believe that I am sponsored by APOD or that I sponsor them , but I just love that great source of very nice pics, interesting info and tons of very good links!

[edit on 21-12-2004 by SpookyVince]

Be lucky that you guyz wont be around when our life giving sun decideds to Nova! Of course earth would already be gone b/c of the Big red giant transformation!/
What is the limit on how close a supernova would be to destroy earth? 25 lightyears?