Why can't we see this?

[Leovinus]

A picture of the Sombrero Galaxy M104 was in my Space Page-a-day calendar yesterday. It said that it has an apparent size of 1/5 the diameter of the full moon. So why do we need a telescope to see it if it so big? <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

It still makes me wonder how something so big can be so dim. <div class="Discussion_UserSignature"> </div>

 

[bbrock]

I have news for you. The Andromeda Galaxy is about 30 times closer and many times brighter then M104. A full 4 1/2 degrees wide. This is about 8 to 9 times larger then the moon. On a crystal clear night, you may just be able to see a faint smudge of its center. <br /><br />Clear Skies<br />Bill

 

[jcdenton]

At 8th magnitude you probably could see a slight trace of it with some binoculars. <div class="Discussion_UserSignature"> </div>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>It still makes me wonder how something so big can be so dim.<p><hr /></p></p></blockquote><br /><br />Light follows the inverse square law; the Sombrero Galaxy is very far away, so it's light is very very very diffuse by the time it finally gets here. You can only make out such incredible detail with long exposures. Even the biggest telescopes don't get this much detail unless they keep the shutter open for a long time. That's probably the biggest source of disappointment for beginner stargazers; the spectacular pictures you see in magazines are all long exposures.<br /><br />If you want to see a galaxy's structure fairly clearly with the naked eye, you'll have to travel to the Southern Hemisphere to get a look at the Magellanic Clouds. <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>

 

[Saiph]

It's a matter of surface brightness. It's putting out a lot of light, but its spread across the entire surface. As such no single area (or in the case of andromeda only a single area) crosses the physical threshold of the eye's sensitivity.<br /><br />you have to remember, galaxies are an entirely different class of distance compared to everything else you see. <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>

 

[tom_hobbes]

Have you seen the massive full size Hubble image?<br /><br />http://hubblesite.org/newscenter/newsdesk/archive/releases/2003/28/image/a+warn<br /><br />A lovely 211 meg.<br /><br />When you see it in the foreground with all those tiny dots of galaxies arrayed behind it, sure does give one a sense of scale.... <div class="Discussion_UserSignature"> <p><font size="2" color="#339966"> I wish I could remember<br /> But my selective memory<br /> Won't let me</font><font size="2" color="#99cc00"> </font><font size="3" color="#339966"><font size="2">- </font></font><font size="1" color="#339966">Mark Oliver Everett</font></p><p> </p> </div>

 

[jcdenton]

<font color="yellow">When you see it in the foreground with all those tiny dots of galaxies arrayed behind it, sure does give one a sense of scale....</font><br /><br />Makes one feel very humble doesn't it? <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

Deep images like that are what make me convinced that we can't possibly be the only intelligent beings in the universe. <div class="Discussion_UserSignature"> </div>

 

[majornature]

There is not enough light energy to "bounce off" since it is far away. Nice Picture! I like it alot. <div class="Discussion_UserSignature"> <font size="2" color="#14ea50"><strong><font size="1">We are born.  We live.  We experiment.  We rot.  We die.  and the whole process starts all over again!  Imagine That!</font><br /><br /><br /><img id="6e5c6b4c-0657-47dd-9476-1fbb47938264" style="width:176px;height:247px" src="http://sitelife.space.com/ver1.0/Content/images/store/14/4/6e5c6b4c-0657-47dd-9476-1fbb47938264.Large.jpg" alt="blog post photo" width="276" height="440" /><br /></strong></font> </div>

 

[tom_hobbes]

Yes, it's inconceivable that The Earth contains the only life in all of this, and that we represent the only intelligent life.<br />I've said it before but it's still true, looking at that image makes me feel like all the parties in the world are going on out there, all those little lights, and I’m not invited. <div class="Discussion_UserSignature"> <p><font size="2" color="#339966"> I wish I could remember<br /> But my selective memory<br /> Won't let me</font><font size="2" color="#99cc00"> </font><font size="3" color="#339966"><font size="2">- </font></font><font size="1" color="#339966">Mark Oliver Everett</font></p><p> </p> </div>

 

[Leovinus]

And the saddest part is that light from any of those remote civilizations took so long to get here that they are all extinguished. <div class="Discussion_UserSignature"> </div>

 

[tom_hobbes]

Aye, being self aware is ultimately a melancholly business... <div class="Discussion_UserSignature"> <p><font size="2" color="#339966"> I wish I could remember<br /> But my selective memory<br /> Won't let me</font><font size="2" color="#99cc00"> </font><font size="3" color="#339966"><font size="2">- </font></font><font size="1" color="#339966">Mark Oliver Everett</font></p><p> </p> </div>

 

[Saiph]

Thus the Hitchikers Guide character Marvin. <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>