Are the Colors of Nebulae Truly Visible?

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Dessgeega

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<p>Hey guys!&nbsp; I know this is probably a rudimentary question, but I'd love an answer to this:</p><p>You know how images of nebulae from the Hubbell are always black and white; well, what does the color represent in the edited representations of the nebulae?&nbsp; If you were to, say, hop in your car, and fly it through a nebula, would there be any color visible besides black and white? &nbsp;</p><p>Thanks in advance to everyone for their input, and I'd love to hear what all of you have to say!</p><p>Sincerely,<br />&nbsp; &nbsp;&nbsp; Dessgeega </p>
 
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CalliArcale

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hey guys!&nbsp; I know this is probably a rudimentary question, but I'd love an answer to this:You know how images of nebulae from the Hubbell are always black and white; well, what does the color represent in the edited representations of the nebulae?&nbsp; If you were to, say, hop in your car, and fly it through a nebula, would there be any color visible besides black and white? &nbsp;Thanks in advance to everyone for their input, and I'd love to hear what all of you have to say!Sincerely,&nbsp; &nbsp;&nbsp; Dessgeega <br /> Posted by Dessgeega</DIV></p><p>Alas no, the colors are not as they seem.&nbsp; For one thing, the Hubble pictures are not always true color -- sometimes false color is used to highlight certain spectra for scientific purposes.&nbsp; Also, it can be easier to distinguish contrast if the colors are tweaked a bit.&nbsp; But even in the "true color" images, it's not what you'd see with the naked eye, for two reasons:</p><p>1) These are VERY long exposures.&nbsp; To the naked eye, nebulae appear white.&nbsp; There simply isn't enough light to activate the color-sensing cones in your retinas, so you instead see it only with your more sensitive rods, which are effectively colorblind.</p><p>2) These are seen at large distances.&nbsp; Nebulae cover very large areas and are very diffuse; if you got up close to them, they would seem to fade out and disappear, much as haze on Earth is visible in the distance but seems to disappear when you drive into it.&nbsp; At most, you might notice that distant stars are fainter than they ought to be. </p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
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weeman

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hey guys!&nbsp; I know this is probably a rudimentary question, but I'd love an answer to this:You know how images of nebulae from the Hubbell are always black and white; well, what does the color represent in the edited representations of the nebulae?&nbsp; If you were to, say, hop in your car, and fly it through a nebula, would there be any color visible besides black and white? &nbsp;Thanks in advance to everyone for their input, and I'd love to hear what all of you have to say!Sincerely,&nbsp; &nbsp;&nbsp; Dessgeega <br />Posted by Dessgeega</DIV><br /><br />Calli is right. The only argument that I have is the Orion Nebula. I've looked at it many times through my small 4.5" telescope and I can definitely pick out some color. Not a lot, but I can usually distinguish sort of a pale amber/pale pink through my scope. Of course, it more than likely looks different when viewed from Earth versus being viewed from space (no atmosphere). </p><p>Nebulae are very large, often spread out over distances much larger than our solar system, and even several light years. So just as Calli said, when you're within the nebula, you would hardly notice it. </p><p>In the long run, if the Hubble pictures are published in books and websites, then they are definitely enhanced for our viewing pleasure! Also take note of which spectrum that Hubble is looking at when viewing a particular nebula. Is it visible light or infrared light? Ultraviolet or x-ray? etc. </p> <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>
 
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bearack

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Alas no, the colors are not as they seem.&nbsp; For one thing, the Hubble pictures are not always true color -- sometimes false color is used to highlight certain spectra for scientific purposes.&nbsp; Also, it can be easier to distinguish contrast if the colors are tweaked a bit.&nbsp; But even in the "true color" images, it's not what you'd see with the naked eye, for two reasons:1) These are VERY long exposures.&nbsp; To the naked eye, nebulae appear white.&nbsp; There simply isn't enough light to activate the color-sensing cones in your retinas, so you instead see it only with your more sensitive rods, which are effectively colorblind.2) These are seen at large distances.&nbsp; Nebulae cover very large areas and are very diffuse; if you got up close to them, they would seem to fade out and disappear, much as haze on Earth is visible in the distance but seems to disappear when you drive into it.&nbsp; At most, you might notice that distant stars are fainter than they ought to be. <br />Posted by CalliArcale</DIV></p><p>Brilliant question and an even more brilliant answer.&nbsp; I truly never knew this.</p> <div class="Discussion_UserSignature"> <p><br /><img id="06322a8d-f18d-4ab1-8ea7-150275a4cb53" src="http://sitelife.space.com/ver1.0/Content/images/store/6/14/06322a8d-f18d-4ab1-8ea7-150275a4cb53.Large.jpg" alt="blog post photo" /></p> </div>
 
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crazyeddie

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Calli is right. The only argument that I have is the Orion Nebula. I've looked at it many times through my small 4.5" telescope and I can definitely pick out some color. Not a lot, but I can usually distinguish sort of a pale amber/pale pink through my scope.&nbsp;<br /> Posted by weeman</DIV></p><p>I once looked at the Orion nebula through a 22-inch reflector at Lick Observatory. &nbsp;Perhaps everyone's eyes are different, but even through that relatively large instrument, the only color I saw was bluish-green. &nbsp;That's the only color I ever see when I view nebula, even in my 11" reflector.&nbsp;</p> <div class="Discussion_UserSignature"> </div>
 
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derekmcd

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I once looked at the Orion nebula through a 22-inch reflector at Lick Observatory. &nbsp;Perhaps everyone's eyes are different, but even through that relatively large instrument, the only color I saw was bluish-green. &nbsp;That's the only color I ever see when I view nebula, even in my 11" reflector.&nbsp; <br /> Posted by crazyeddie</DIV></p><p>Color is in the eye of the beholder. <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-smile.gif" border="0" alt="Smile" title="Smile" /> </p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Color is in the eye of the beholder. <br />Posted by derekmcd</DIV><br /><br />If it's bright enough. When photons are few only the rods can respond, that data is in black and white. When it is bright enough, there are enough photons for the cones (which provide color vision) to respond.</p><p>For most people that transition occurs at about a +2 magnitude meteor., which is a point source; i.e. lots of photons in one spot. For a nebula, whether close or far, it's difficult. I think I have seen a faint greenish glow in the Orion nebula through a scope with the image moderately magnified. It's so close to the detection level that it could just as easily be my imagination.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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