T Nation

The Hubble Ultra Deep Field in 3D


..simply astonishing: http://www.youtube.com/watch?v=oAVjF_7ensg&feature=player_embedded


Carl Sagan - Pale Blue Dot: http://www.youtube.com/watch?v=p86BPM1GV8M


I've loved Carl Sagan all my life but never heard his voice. Thanks.


Computer animation. Wow!


Umm... the actual images of the galaxies where certainly no computer animation. As for the "3D" bit at the end, it was still complied using actual images. It's not like someone just made it all up...

On a lighter note, why hasn't anyone pointed this thing at the moon!!!?!? If we really did go to the moon in 69, that would shut all the skeptics up.


Made it up? no, but those are not real Hubble images. I prefer the artist renderings anyway.


A standard microscope can magnify objects up to 140X, yet you would not use it to look at the moon to make it bigger. Likewise, a pair of binoculars can magnify an image a hundreds of yards away so you can see clear detail, but you could not view cell structure with it. Just because something can give clear images of objects light years, and trillions of light years away, does not mean it can give high resolution images of objects which are much much closer.



..the reason why i love these clips is the sheer insignificance of us, and the earth. Like Sagan said; we exploit eachother and ravage the planet without realising this, as if somehow we matter in the grand scheme of things...


Umm... it was a joke referring to a thread a few weeks back. Besides, we established that this ISN'T the reason the Hubble can't take clear pictures of the moon. The reason is that the Hubble simply doesn't have the needed resolution to see small things on the moon, and interestingly enough it can be mathematically shown that the stated specs on the Hubble, while not giving it enough resolution for small objects on the moon, do give it enough resolution to take deep space pictures.

In simpler terms the real reason is that although the objects Hubble sees in deep space are REALLY REALLY REALLY far away, they're also REALLY REALLY REALLY big. A better analogy is how a pair of binoculars can pick out craters on the moon, but not, say, read the lettering on a water tank 10 miles away.


it has to do with the angle of the aperture in relation to the object. A good pair of binoculars could read lettering on a water tank 10 miles away and even cancel out transverse motion caused by shaking limbs.

But you guys' scales are WAY, WAY off.

We're talking about stuff that is "billions and billions" (hat tip to Carl Sagan) times as far away and millions and millions times as large. It requires lots of light to make it to the aperture to get a good resolution on these objects.

These objects could never be seen as "3D" once transformed into 2D representations. The finished product has information added to it based on a best guess of what a complete object would look like. It's art.


Wow, I wonder how many times I'll have to do this. No. While things like the aperture affect the sorts of images Hubble can take, the problem with Hubble imaging small objects on the moon is essentially a problem of resolving power. It simply doesn't have good enough resolution to take pictures of anything on the moon near the scale of stuff like the orbital lander. Weren't you even in the thread where we went over this math?

You're reading WAY to much into my binocular comment. My comment was only meant to provide a rough analogy about how Hubble can see some things that are really far away, but yet not see other things that are relatively close by. The reason of course is because those things really far away are proportionally bigger then the things relatively close.

I'm quite well aware of the scale involved, I don't need silly analogies in order to do computations with distances in the million and billion-light-year range. As I said, ultimately the Hubble's problem isn't the design of the aperture, but absolute limitations of its resolving power given the size of its mirror.

I'm no expert, but from what they said in the video it sounds more precise then what you're giving it credit for. It sounds like what they did was take a 2D image of a bunch of galaxies, measure the red shift of each galaxy to calculate distance, and then simply render a 3D (or really, a "two and a half D") video model showing the galaxies at proportionally correct distances from one another. If this is what they did, then there's no real guess work involved... just sound calculations done based on physics. I wouldn't call this "art".


Hahahaha, thanks for this post, you just made me spit out what I was drinking lol


You missed a good thread, ha.


Which thread would that be?


Ah, it's a few weeks old now, but there was one where someone was seriously asking that question. A few people including myself did some searching on the imaging power the Hubble and figured out the stuff I've kinda been summarizing in this thread. It's easy to show that the intuitive argument that "Well, because the Hubble can image galaxies zillions of light years away it must be able to pick up the little old lander on the moon" is just wrong.