Posted on 02/03/2012 7:27:00 PM PST by Clintonfatigued
That's what its inhabitants said when they discovered the mini planet Earth....
I don't know. I think it would mean much more if someone invented warp drive so we can get there. A planet that's in range is worth the whole rest of the universe in the bush. ;)
How do you know that?
Your premise has no basis what so ever
“The Drake equation says otherwise.”
The Drake Equation is B.S., It seems simple with everything appearing to be proportional, But indeed they are not. The devil is in the details... It’s not solvable without making stuff up.
Thanks. I was thinking white dwarfs. Red Dwarfs are the energy efficient lightbulbs of the universe. Not much light but they’ll last a long time.
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I don’t know the whole story. Stars in the sky come in various sizes and colors. The Sun we have is a medium-sized yellow star.
If the star is light on heavy metals, does it manke it more unstable?
Or do we know enough about stars to determine that?
I know - Wiki should have been my first stop.
But digging through a H-R Diagram is such a puzzle for me I was hoping a science chatterbox would lay it all out in a couple of simple sentences.
Learned several cool new things, though, which you may already know.....
Red dwarfs convect helium throughout the star, thus there is no helium ash build up in the core.
The smallest red dwarfs can theoretically burn for more than a trillion years.
Alpha Centauri B is an orange dwarf.
Good question. I don’t know.
An all helium star wouldn’t last long; a helium core can’t sustain a star very long because helium burns faster than hydrogen. Once hydrogen is used up at a star’s core, it’s on its last legs.
If a star somehow formed in a super iron-rich cloud, such that the star was largely iron from the get go, that would probably cause some funny behavior.
I don’t know if we know enough about stars to answer your question, but I know that I don’t! :-)
bump
thanks
Stars are plotted according to their temperature (horizontal axis) and luminosity (vertical axis). Because temperature and color are correlated, you will sometimes see the horizontal axis represented as a color axis instead of a temperature axis. This comes as no surprise. We know from everyday life that color and temperature are correlated; if you heat a coat hanger on a stove top it will first glow red. Then as it gets hotter, orange, yellow, and if you can get it hot enough, blue and white. Same with stars.
Another popular horizontal axis that you'll often see has to do with a star's spectral classification: O,B,A,F,G,K,M (Oh, be a fine girl, kiss me). Type O stars are the hottest, type M the coolest. The Sun is a type G star.
Likewise with the vertical axis. Luminosity and absolute magnitude are directly related. So you'll often see the vertical axis represented as absolute magnitude instead of luminosity.
When you plot all the stars within 25 parsecs of the Sun, a surprising pattern emerges. First, there is the swervy-curvy line that stretches from the upper left to the lower right. It turns out that this is where stable, mid-life stars, called "main sequence" stars, reside.
As stars like the Sun move into old age, they nova, blow off their outer layers and migrate off the main sequence into the upper-right region of the H-R diagram. These are the red giants. What remains of the star, the part that didn't blow off into space, collapses down to a dense hot object called a "white dwarf," or perhaps, if the original star was massive enough, to a neutron star.
There is so much more. I'd encourage you to Google H-R diagrams and to do a Google image search for them as well, and check out all the different forms. You can tell a lot about a star from it's position on an H-R diagram.
Well, I'm about chatterboxed out! And you are as well, I imagine. Ask a chatterbox for a few sentences and you'll get paragraphs! :-)
I did not know there is no helium ash build-up at a red dwarf's core, thanks!
I can still remember the nightly tears of math desperation.
I pretty much avoided the subject until 2005.
My local education channel carries excellent college level astronomy courses, and the University of Washington chips in with several lecture series each year.
I still cannot believe how little I knew about the universe before then!
And - realized why I'd never heard of red and orange dwarfs...
I think I always saw them called M stars and K stars before.
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