McNeil Nebula

[claywoman]

Okay...I was looking at the pictures of the McNeil Nebula and I want to congratulate him on his extraordinary find! However, I do have a question that puzzles me. I've been reading more and more on stars and their colors, and they call this a 'newborn' star, but I thought new stars were hot and thus blue, but this one is red, which I thought denoted an 'old' cooling star. I'm confused here...

 

[claywoman]

Could someone please help me here? I know I'm not a scientist, I'm a historian but very interested in this subject and I'm confused here...

 

[thalion]

There are two kinds of star colors. One is related to a star's spectral class, which falls into one of seven categories (nine, if you include brown dwarf classes): O, B, A, F, G, K, M. The hottest are the massive O stars, which are blue-white, and the coolest are the low-mass M stars, which are reddish. Our Sun is a G2 star, making it a kind of yellow--of course, only noticeable if we could see it from a distance. <br /><br />The other color of a star is its apparent color, which depends largely on how much dust is obscuring a star's light. Interstellar and nebular dust preferentially absorbs blue light, making stars look redder than they really are.<br /><br />The short answer to the question is: A star's intrinsic color is dependent mainly on its mass and age. A new star, one that has actually fired up fusion in its core, can be any color from red to blue-white, depending on its mass. "Red" only denotes old when it comes to red giant and supergiant stars, which one would never see still cloaked in the dust of their formation.<br /><br />More on spectral classes:<br />http://www.astro.uiuc.edu/projects/sow/spectra.html

 

[Saiph]

thalion: Good post.<br /><br />Claywoman: Don't get frustrated at a long time for a response. This board (especially the science sections) can be slow. Many people don't feel up to the task of answering, or don't know. And so they wait.<br /><br />I think they're more qualified than they think, and should pipe up. And if they're mistaken a bit, another persons response should help clear it up. <br /><br /><br />But, as thalion says, color is an indication of temperature (which is intimately related with spectral type) not age. At least, not a direct indication of age.<br /><br />From that, and other clues, mass and age can be estimated. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[claywoman]

I want to thank all of you for helping me out here. If I weren't a historian my second choice would have been astronomy except I'm math deficit!! I got A's and B's in Algebra and stats but I knew any higher and I'd be in big trouble!!! I just found this site and I come back to it everyday and alway, always find new and interesting stories and pictures! I am so happy here!!

 

[Saiph]

glad we could be of service.<br /><br />Feel free to kick up your feet, take off your hat and make yourself at home! <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>