Stars

Comments and questions about the APOD on the main view screen.
Em
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Stars

Post by Em » Mon Dec 12, 2005 9:12 am

How big is the largest star on record? And where is it?

harry
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Post by harry » Mon Dec 12, 2005 10:03 am

Do you want size or mass.

Some stars are only a few kilometers across with the same mass as our sun.

While others are 100 times the size of our sun and yet their mass is only a fraction.

Have a nice day
Harry : Smile and live another day.

Em
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Post by Em » Mon Dec 12, 2005 12:09 pm

Thank you for your response Harry :o.

I meant size.

Would you be able to refer me to a website or like that answers all the basic questions on the universe that one might ask e.g how old is the earth? Do we know if there is an order in which our planets were formed? etc.

Empeda2
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Post by Empeda2 » Mon Dec 12, 2005 12:36 pm

Welcome em :D

I find that http://www.nineplanets.org was always a good source for info for the solar system.

As for massive stars - try googling 'Eta Carina' and also 'Wolf-Rayet Stars" - they're pretty big....
The Artist Formerly Known as Empeda

Em
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Post by Em » Mon Dec 12, 2005 9:13 pm

Thanks Empeda 2 :) .

Have a great day!

Dani
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Post by Dani » Mon Dec 12, 2005 9:23 pm


Em
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Post by Em » Mon Dec 12, 2005 10:17 pm

Thanks Dani, that's exactly what i was after!

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Orca
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Post by Orca » Tue Dec 13, 2005 2:40 am

The universe simulator Celestia makes a vivid illustration of the differences in diameters stars can be. I took these screenies from within the program.


Here's the Sun, as seen from Saturn, at about 9 AU (Astronomical Units...1 AU is equal to the distance from the Sun to the Earth):

Image

Just a tiny yellow dot.

Now here's the red giant Betelgeuse (in the constellation Orion) at a distance of 9 AU:

Image

The giant doesn't even fit in the screen. Also, the distances are from the surfaces of the two stars...


:shock: [/list]

harry
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Post by harry » Tue Dec 13, 2005 4:27 am

Hello Dani

Thank you for the links
http://antwrp.gsfc.nasa.gov/apod/ap971008.html
http://www.xs4all.nl/~carlkop/lbv1806.html

These Giant stars are very interesting.
Has anybody calculated or estimated the mass.

I'd love to know the size of the Core.
Harry : Smile and live another day.

Em
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Post by Em » Tue Dec 13, 2005 4:38 am

How is the size of the core calculated?

harry
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Post by harry » Tue Dec 13, 2005 4:48 am

By guesstimate and by the temperature and by the graviational effects on the surrounding space bodies.

The problem with distant giants is that you maybe looking at a multiple of stars looking as one.

My Question is that if you have a star 5 million times the size of our star. Why does it not behave like a black hole.
Harry : Smile and live another day.

Empeda2
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Post by Empeda2 » Tue Dec 13, 2005 9:29 am

Because we're talking about physical diameter/volume - not the mass of the star.
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harry
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Post by harry » Tue Dec 13, 2005 10:03 am

Something fishy is happening with the giant stars. There is more than meets the eye.
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Em
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Post by Em » Tue Dec 13, 2005 10:31 am

What do you mean Harry?

harry
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Post by harry » Tue Dec 13, 2005 11:43 am

In the Links above they are talking about stars 5 to 40 billion times that of our sun.


Something does not add up

I may need sleep

smile,,,,,,,,,,,,,i feel warped out
Harry : Smile and live another day.