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Magellan II's Adaptive Optics Top Hubble's Resolution
muon-catalyzed writes "The incredible 'first light' images captured by the new adaptive optics system called Magellan|AO for "Magellan Adaptive Optics" in the Magellan II 6.5-meter telescope are at least twice as sharp in the visible light spectrum as those from the NASA's Hubble Space Telescope. 'We can, for the first time, make long-exposure images that resolve objects just 0.02 arcseconds across — the equivalent of a dime viewed from more than a hundred miles away,' said Laird Close (University of Arizona), the project's principal scientist. The 6.5-meter Magellan telescopes in the high desert of Chile were widely considered to be the best natural imaging telescopes in the world and this new technology upgraded them to the whole new level. With its 21-foot diameter mirror, the Magellan telescope is much larger than Hubble with its 8-foot mirror. Until now, Hubble always produced the best visible light images, since even large ground-based telescope with complex adaptive optics imaging cameras could only make blurry images in visible light. The core of the new optics system, the so-called Adaptive Secondary Mirror (ASM) that can change its shape at 585 points on its surface 1,000 times each second, counteracts the blurring effects of the atmosphere."
Is it me, or is that summary incredibly difficult to read?
Try again after a cup of coffee.
Right in the summary we have a comparison between the 6.5 m Magellan telescope and the 8 ft Hubble.
I found it easy to read and don't feed the trolls!
I suspect it will take a bit more than coffee.
Science advances one funeral at a time- Max Planck
"The 6.5-meter Magellan telescopes in the high desert of Chile were widely considered to be the best natural imaging telescopes in the world "
WTF is natural imaging ?
Are other telescopes unnatural ?
Despite this, I'd still like to see the images of a 30m lunar orbit space telescope.
They probably meant 'natural' as in 'direct imaging', instead of post-capture image processing to correct artifacts.
I think they're referring to visible light, not radio, IR, UV or X-Ray.
Help I am stuck in a signature factory!
As to the above drama about mixing measuring units, the article says:
These images are also at least twice as sharp as what the Hubble Space Telescope (HST) can make because the 6.5m Magellan telescope is much larger than the 2.4m HST.
So there you go. Both measurements in Imperial European Units.
But then I read on, and was pretty stoked to see them discovering things like this.
MagAO was then used to map out all the positions of the brightest nearby Orion Trapezium cluster stars and was able to detect very small motions compared to older LBT data, a result of the stars slowly revolving around each other. Indeed, a small group of stars called Theta 1 Ori B1-B4 was proved to be likely a bound “mini-cluster” of stars that will likely eject the lowest mass star in the near future (see figure 4). This result has just been published in the Astrophysical Journal.
Nice! I'd love to see a time-lapse video over the course of the next million years watching this black sheep star get flung out of its little flock.
fifth sigma, inc.
Hubble was sent into space with a major glitch in its primary mirror. While yes, we were able to give it, achem, corrective lenses for its near-sightedness, it was never able to perform to original specifications. This project, by comparison... doesn't have a defect in one of its most important components. So I don't know if this is an entirely fair comparison to make...
The fact is, they solve problems in two separate ways -- Hubble is a direct observation. There's no distortion, the light is the original and it's not smeared by atmospheric effect. Adaptive optics are amazing, but they're still additive in nature; You can photoshop, cut, and paste, but it'll never be quite as accurate as direct observation can be. That said, quite a lot can be done with it, and its a welcome addition especially in the age of limited scientific budgets for astronomy! I guess all I'm trying to say is... it's supplimentary, it is not a replacement for the kind of work Hubble did. We still need a replacement Hubble (obviously... with updated tech) for some observations.
#fuckbeta #iamslashdot #dicemustdie
What they rarely mention in these sorts of press releases (everyone with AO system has a "better than Hubble" press release) is that the cost of getting to that resolution is losing most of the light along the way. It's not hard to beat HST with perfect atmospheric correction, as Hubble is only a 2.4 m aperture, and nearly every AO system is on a larger telescope. It's just that the correction is achieved by sufficient optical contortions that only a small fraction of the original light actually makes it to the detector.
My personal experience is that even the largest and most sensitive AO system in the world (NIRC II on Keck II with laser guide star) still really struggles make an observation in 20 minutes that Hubble can do in 5 minutes. If anyone were to launch a >3 m aperture visual-band space telescope (NOT JWST, that's IR), it would blow all these AO systems out of the water.
the Magellan II 6.5-meter telescope... [w]ith its 21-foot diameter mirror
Oh, for... one or the other, c'mon.
systemd is Roko's Basilisk.
It wouldn't need adaptive optics. Those correct for atmospheric aberration, and the moon doesn't have any atmosphere.
However, I don't see the point of lunar rather than orbiting. Lunar has gravity, which must be compensated for in pointing the telescope, and half the sky is invisible at any instant. Orbiting has full access to the whole sky, and no pesky stray forces on the mirror.
Consciousness is an illusion caused by an excess of self consciousness.
Just another reason we need space less and less. We can explore this vast and empty vacuum just fine from right here.
But without space, we wouldn't be able to enjoy heroic stories about the maintenence staff using up an eight hour spacewalk to MacGyver open an access panel on the telescope. What fun is that?
It wasn't dummed-down, and nearly everything is these days.
stay FUCKING AWSOME Anonymous Coward!
All of these things are why the James Webb is going to go to the Lagrange point, rather than orbit.
Orbit is a dumb place to be for a telescope. :-)
I thought the reason for the JWT to be at the Lagrange point was shielding from the sun. With supercooled IR sensors, the less sunlight the better. The life of the JWT is determined by how long its coolant lasts, And the Earth makes a good sunshield. The same is not true for an optical telescope - though any darkness is good, and coolness probably helps. But there is not the same driving need for an optical telescope to be kept cold as there is for an IR one.
Consciousness is an illusion caused by an excess of self consciousness.
I think naturel imaging is used to rules out interferometry
I suspect it will take a bit more than coffee.
Try adding just a touch of Ketamine, it takes that caffeine jitter away...
CAUTION:
Ketamine is not intended for use by humans and may be unlawful in your area. Additionally, some people do experience the side effect of waking up with their pants around their ankles.
You have the right to remain sentient. If you give up the right to remain sentient, you will be elected to public office
You do realize there's just a bit of time lag here?
The Hubble was supposed to launch in 1983 (delays in building and the Challenger disaster held it up till 1990). So, it's at best 30 year old tech (and actually since it was space rated, a good bit older than that).
The Magellan II is brand spiffy new and can take advantage of many things that Hubble can't since it needs to be at least somewhat rad hard.
Granted that Hubble has been upgraded, but I don't think it's a fair comparison.
If we ever get the James Webb Telescope launched, that might be a fairer comparison.
Did you actually read his comment? Or just reply to the subject line?
Not to mention, only the ignorant think that "price" is only reckoned in dollars.
I don't know what the current state of the art is, but once upon a time it was only possible to correct a for atmospheric variations over a very narrow field of view. You will notice that the first light images are of binary stars and not of whole nebulae or galaxies. I don't think this is an accident.
We can finally quiet the "moon landing was a hoax" nutjobs. With the ability to make long-exposure images that resolve objects just 0.02 arcseconds across — the equivalent of a dime viewed from more than a hundred miles away", we can actually take pictures of all the junk we left behind as proof that we were actually there.
Veritas patesco per quaestio questio. Truth is revealed through questions.
It's you.
So when do we get the really cool pictures from Magelan II, in higher resolution than we got from Hubble?
Iconic photos like Mars:
http://commons.wikimedia.org/wiki/File:Mars_Hubble.jpg
Jupiter:
http://commons.wikimedia.org/wiki/File:An_Ancient_Storm_in_the_Jovian_Atmosphere_-_GPN-2000-000910.jpg
Saturn:
http://commons.wikimedia.org/wiki/File:Saturn_with_auroras.jpg
And the Hubble Deep Field:
http://commons.wikimedia.org/wiki/File:Hubble_ultra_deep_field.jpg
And completely off-topic, how often do you see a color photo of the moon:
http://www.astro.virginia.edu/class/oconnell/astr121/im/moon-color-mosaic-NCarboni.jpg
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Look up the actual original specs of the blah blah arcseconds blah blah nanometers blah blah resolution blah blah detector blah
You're confusing two separate concepts. Angular resolution dictates how well an optical device can differentiate between two objects close together. It's a component of resolution, not resolution itself. Resolution is determined by a variety of things... and spatial resolution is what I'm interested in, not the number of gigamegasuperdoodapixel count. Magellan's an impressive piece of work, but it's not a replacement for putting a telescope in orbit. It's supplimentary, and that's what you and all the other anonymous coward/trolls bitching that "oh she doesn't know what she's talking about!" are continually and epicly failing to understanding.
And the fact that you try to associate adaptive optics as some software trick that fills in data with the same signal to noise ratio shows you fundamentally do not understand what it does.
Adaptive optics reduce wavefront distortions in the incoming signal... think 'funhouse mirror'... adaptive optics measures the distortions and then creates a reverse biased signal to put back together what the image might have looked like before it was warped. In terms of atmospheric distortions, these are continually changing, and adaptive optics relies on fixed points of reference to build a complex topological matrix which the input signal is rendered into and then a normalized output is produced which minimizes the distortion. Good enough of an explaination? Good.
Now let me explain a new concept to you: Heterodyning. Whenever you take two waves and smash them together into any receiver, be it optical, RF, magnetic, whatever... the two signals merge (heterodyne) to form a new signal. This is the fundamental basis that all radio communication is based on -- you create a carrier wave, and then modulate it (heterodyne) with a lower frequency secondary signal, which is then 'carried' by the first one. Radio waves and light waves run on similar physics.
You can do an impressive amount of signal analysis to create an approximation to the original signals (decoupled) but that's all it is: An approximation. Shannon's Law dictates the exact amount of information that can be extracted; it is an absolute theoretical limit that cannot be exceeded by any amount of 'adaptive' trickery.
A telescope in orbit will be capable of a greater degree of receiver sensitivity. Period. This is physics. You cannot argue your way out of this, no matter how hard you troll, or try to rationalize it, or inflate your own ego, or threaten me, or ridicule me, or whatever. Physics says no, ok? Now whether you can actualize that potential, whether it's practical, or eve necessary... those are good questions. But those are engineering questions. Physics dictates anything you put in orbit, all other things being equal, will give you a better image. The end.
I don't know how else to explain to the clueless hordes that have taken over slashdot... you think because you can google something that makes you a genius... but it doesn't. You say the words, but you do not understand. That's the difference between knowledge and wisdom.
#fuckbeta #iamslashdot #dicemustdie
Telescopes on the surface make up for losses in receiver sensitivity by being frickin huge. Sure, if you put the same size mirror in space and on the ground, you'd rather have the one in space. But that's not how it works. The ones on the ground are cheaper, so for the same cost you can get a much bigger one. Sensitivity is NOT why you want space telescopes.
Space telescopes *used* to have an unbeatable advantage in natural image resolution because they didn't have to deal with the atmosphere. Then someone invented adaptive optics.
Space telescopes still have several advantages. There are no clouds, they can (usually) see the whole sky, and they can often do long continuous observations without having to stop for little irritations like daytime. But the biggest advantage is that they can observe wavelengths that are absorbed strongly by the atmosphere.
Astronomers are proposing to build a 100 m ground telescope: http://en.wikipedia.org/wiki/Overwhelmingly_Large_Telescope.
It was also cancelled. But in favour of a 39 m one.
Who said Low orbit? How much can you see from geostationary orbit? Even the Lagrange point has some blind angles - intentionally, to hide the sun. Orbit is not one place.
Consciousness is an illusion caused by an excess of self consciousness.
http://tinyurl.com/k72g6rq
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