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Hubble's Upgrade: Pretty Pictures
EReidJ writes "The Hubble Space Telescope has come out with astonishing new pictures, our "deepest glimpse[s] into the depths of space and time". An article on the photos is here. These are striking in their beauty, and are sure to become commonplace desktop images in the next month. The official site to view all of the photos is here, but the site's already going pretty slow. washingtonpost.com has the four photos in series on its home page." There are also stories on space.com and MSNBC.
Neat! Also noteworthy is apod, Astronomy Picture of the Day, which also has a brief explanation of all the stuff they post. Of course, most of those pictures are as much a work of human art as photos, since few of the pictures are made of stuff in the visible spectrum, so all those vibrant colours are quite fake. Still looks nice, though. :)
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Go here... Ill get as many as i can, these are sweet :)
Cybie! aka Ralph Bonnell
http://www.msnbc.com/c/0/77/999/ssMain.asp?fmt=Chi ld&0ss=N%r0077999
It's going pretty fast still, and MSNBC did a serious upgrade for the Olympics, so I doubt it will get Slashdotted.
modern choral music...
The pictures are also available on Yahoo, which I'd bet will be able to handle a slashdotting.
Here they are.
-- Have you ever noticed that at trade shows, Microsoft is always the company that is handing out stress balls?
If all continues to go well, the camera will also spend some time on an improbable quest to take the first picture of a planet outside our solar system.
I don't think that HST is going to be the first telescope to successfully image an extrasolar planet. It's magnification and capabilities are just barely at the point where it would be able to spot one. I think the first telescope to image an extrasolar planet will be SIM (Space Interferometry Mission), which is currently slated to go up some time around 2009. It uses optical interferometry to gain tremendous increase in magnification and precision. It will be ~100,000x more precise than HST with an accuracy of 1-4 Microarcseconds. Of course, it is made to have a very small field of view so it won't make HST or other medium to wide field of view scopes obsolete. But I can't wait to find some of the results that come out of that project.
I drink to prepare for a fight; tonight I'm very prepared. -Soda Popinksi
This will get us by until the Hubble Heritage Site gets ahold of them or the main site becomes un-/.ed.
There is a technology called active optics that can be applied to ground-based observations to 'clean up' the optical distortions (seeing) caused by the atmosphere.
Most research-grade telescopes these days are Cassegrain telescopes, which means they have two distinct mirrors, the big primary mirror (When you hear sizes of telescopes, they are making reference to the diameter of this mirror: Keck = 10M, UKIRT=4M, etc.), and the smaller secondary mirror which further focuses the beam from the primary into a tight beam suitable for an eyepiece or camera. Basically how active optics works is there are is an extra camera that picks up the wavefronts of the light as it comes through the atmosphere. It then flexes and bends the secondary mirror (much smaller than the primary) in slight ways in order to accomodate for the atmospheric distortions.
The results are drastic. Images that have been created using active optics are much clearer than non-AO images. However, AO is very expensive to use, and to some extent, degrades the quality of the image. Since some of the light is taken away from the original image as it is sent to the wavefront-detecting camera, it reduces the overall light-gathering power of the telescope. Thus, when a telescope is in AO mode, it creates clearer images, but it isn't as sensitive to deeper/fainter sources as when it isn't in AO mode.
I don't think that AO will make earth-based telescopes behave like Space-based ones, but it will indeed help earth-based telescopy to create better images.
I drink to prepare for a fight; tonight I'm very prepared. -Soda Popinksi
Check this animations:
m at ion.html
http://oposite.stsci.edu/pubinfo/pr/2002/11/ani
Right now I'm watching my new desktop image of the tadpole galaxy. And like another poster said, it is amazing and scary to watch all those other galaxies in the background of that image.
'Wallpaper' of these four photos has been generated and can be found on http://hubblesite.org .
they have the full images available on the site. 2.2meg jpegs and 39 meg tiff's
The reason why distant planets, asteroids, and comets are so difficult to see is because they must first reflect light from the sun (going as 1 / r1^2, where r1 is the distance from the sun to the object) and then that reflected light must travel from the object to us (going as 1 / r2^2, where r2 is the distance from the object to us). That means the apparent luminosity scales as
1 / (r1^2 r2^2)
For objects in the outer solar system, r1 ~ r2, so the scaling goes as the inverse fourth power of the distance, as opposed to the usual inverse square law for directly emitted light. When you throw in the additional fact that many of those outer solar system objects like Pluto and Kuiper belt objects are extremely tiny in comparison to the giant planets, thereby reducing their reflecting power even more, you can see why it is difficult to see such distant objects.
I am not familiar with any Hubble observations of Pluto, though I am certain you could get an image if you gathered enough light for a long enough duration. Practically speaking, however, Hubble is primarily useful for getting excellent resolution not possible with ground-based telescopes due to atmospheric effects. Furthermore, it is in very high demand, so that it is only used where ground-based instruments cannot work as well. Ground-based telescopes are still much larger, and have a much greater light-gathering ability than Hubble, however, and are still the instruments of choice when every photon counts, as when astronomers gather specta.
Bob
Science, like Nature, must also be tamed, with a view turned towards its preservation.
This NASA story, Hubble's New Camera Delivers Breathtaking Views Of The Universe, has links to the photos. One of the linked sites, Hubblesite.org has stories such as Hubble's Advanced Camera Unveils a Panoramic New View of the Universe, which has thumbnail photos.
Adaptive/Active optics can work in two ways. One way is to use a bright (and it has to be damn bright) star near the target that one's hoping to look at. Then, by seeing how the atmosphere distorts this (supposedly point-source) star, we can adjust the mirror to compensate. There are different ways to do this that involve just moving the image around or re-shaping the mirror altogether, but I won't go into that here. The trouble with this plan is that it's hard to find a star bright enough in the part of the sky that you happen to be observing. It has to be damn bright, since you have to read out the CCD several times a second in order to compensate for the atmosphere fast enough. The second method uses a sodium-type laser that excites a layer in the atmosphere very high up (i.e. above most of the clouds/water vapor/crap). This behaves as a sort of artificial bright star that one can have anywhere in the sky.
The Center for Adaptive Optics (at UCSC) has a decent simple explanation here.
All of this aside, this will probably NOT render HST obsolete any time soon, since this is rediculously hard to do and has yet to really be done convincingly in any large-scale way, as people at my institution are finding out.
I couldn't tell if you were experimenting with poor-man's cryogenics or looking for the orange sherbet.
Yes, there is no question that the ACS will be useful to image closer objects. It was the Hubble that recently imaged the first Kuiper-Belt object that has been detected with it's own moon (once again suggesting that Pluto's claim on 'planethood' is less logical than emotional).
I'd imagine that the ACS is going to make some stunning pics of bodies in our system, but don't expect them terribly soon - time on the ACS is the main restriction, and somehow those deep-field glamour shots get all the attention/resources.
Maybe they could use it to look for the debris from the Mars Impactors that we sent....
-Styopa
Nice advert free gallery of the photos available from WashingtonPost.com. Nice and big too.
Click for Gallery
So close and yet so far from the world's perfect ID number
Actually, the spikes around the stars are caused by the 'spider' supporting the secondary mirror of the telescope. You won't see this effect in refractor (= plain old lens) telescopes, but they are impossible to make in large sizes.
Bas
Do you think that the whole concept of dark matter is in a lot more danger now that billions of new galaxy's will come to light?
It's the density of matter in the universe that requires the existence of dark matter, not how many galaxies there are. Discovering more galaxies doesn't make any difference - we already know the visible-matter density of the universe.
Far more interesting is going to be using these pictures to work out whether the universe is full of "dark energy" which is causing the universe's expansion to accelerate.
We can't see dark energy (duuuh cos it's dark) but we can work out whether the universe is accelerating or not. It's all rather complicated, and relies on an accurate survey of the distances and speeds of very distant galaxies.
Speed is easy, that's measured from spectral red-shift. Distance is hard. Walmart don't make a tape measure 2 billion light years long, so we need a different method.
Recently, someone worked out a trick to measure the distance. Type 1 supernovae are all about the same brightness, and can be identified by their spectrum. So all we have to do is search for galaxies containing type 1 supernovae. Trouble is, you need to look at a lot of galaxies before you find a single supernova that happens to be going off at the time the photo is taken, and you need to look at a lot of supernovae before you can build up a good statistical picture.
In short, people have done this from Earth. Now they can do it from space with Hubble, looking at galaxies much further away and look at lots of them at once. Expect the controversy over whether or not the universe's expansion is accelerating to be resolved within the next 2 years.
Once more unto the breach, dear friends, once more, Or close the wall up with our American dead!
Common Lisp!
You can find some of the details in this paper: COSI: Adding Constraints to the Object-Oriented Paradigm.
Cool stuff!!