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Everyone loves twinkling stars and moonlit nights—EXCEPT astronomers. But astronomers are crafty people, so they’ve come up with ways to mitigate the distortion that Earth’s thick atmosphere causes for ground based telescopes (from which stars appear to twinkle). And now, a new image-correction technique has delivered the sharpest whole-planet ground-based picture ever. The Very Large Telescope (VLT) performed a record two-hour observation of Jupiter using a breakthrough technique to remove atmospheric blur. And what a result! Just take a look at that gorgeous image…And this new image reveals changes in Jupiter’s smog-like haze, probably in response to a planet-wide upheaval more than a year ago.
Being able to correct wide field images for atmospheric distortions has been the dream of scientists and engineers for decades. Astronomers used a new device called the Multi-Conjugate Adaptive Optics Demonstrator (MAD) prototype instrument mounted on ESO’s Very Large Telescope (VLT)
The new images of Jupiter prove the value of the advanced technology used by MAD, which uses two or more guide stars instead of one as references to remove the blur caused by atmospheric turbulence over a field of view thirty times larger than existing techniques.
“This type of adaptive optics has a big advantage for looking at large objects, such as planets, star clusters or nebulae,” says lead researcher Franck Marchis, from UC Berkeley and the SETI Institute in Mountain View, California, USA. “While regular adaptive optics provides excellent correction in a small field of view, MAD provides good correction over a larger area of sky. And in fact, were it not for MAD, we would not have been able to perform these amazing observations.”
MAD allowed the researchers to observe Jupiter for almost two hours on 16 and 17 August 2008, a record duration, according to the observing team. They were able to take a series of 265 snapshots. Conventional adaptive optics systems using a single Jupiter moon as reference cannot monitor Jupiter for so long because the moon moves too far from the planet. The Hubble Space Telescope cannot observe Jupiter continuously for more than about 50 minutes, because its view is regularly blocked by the Earth during Hubble’s 96-minute orbit.
Using MAD, ESO astronomer Paola Amico, MAD project manager Enrico Marchetti and Sébastien Tordo from the MAD team tracked two of Jupiter’s largest moons, Europa and Io – one on each side of the planet – to provide a good correction across the full disc of the planet. “It was the most challenging observation we performed with MAD, because we had to track with high accuracy two moons moving at different speeds, while simultaneously chasing Jupiter,” says Marchetti.
With this unique series of images, the team found a major alteration in the brightness of the equatorial haze, which lies in a 16,000-kilometer wide belt over Jupiter’s equator. More sunlight reflecting off upper atmospheric haze means that the amount of haze has increased, or that it has moved up to higher altitudes. “The brightest portion had shifted south by more than 6,000 kilometers,” explains team member Mike Wong.
This conclusion came after comparison with images taken in 2005 by Wong and colleague Imke de Pater using the Hubble Space Telescope. The Hubble images, taken at infrared wavelengths very close to those used for the VLT study, show more haze in the northern half of the bright Equatorial Zone, while the 2008 VLT images show a clear shift to the south.
“The change we see in the haze could be related to big changes in cloud patterns associated with last year’s planet-wide upheaval, but we need to look at more data to narrow down precisely when the changes occurred,” declares Wong
Source: ESO
I don’t get it. Jupiter does nearly a quarter of a rotation in two hours – why isn’t it smeared in longitude?
“Not sure the FAA would be too happy to have thousands of powerful lasers pointing into the night’s sky all over the country! “
Yes, because only in USA you’ll get to use this technology (should it be mass marketed)… Come on, get your heads out of your “country”.
Sorry, my bad… Bad day and I just had it with “america” being the only country in the world.
Would be something to have adaptive optic technology advance to a point where it could be used for 12″+ amateur scopes, and affordable as well.
…dream dream dream!
why does it look mishapen?
is there a link to the planet-wide upheaval mentioned? I missed the upheaval.
I wonder how clear images of the Earth from space would be with this technology? I also wonder what the various countries spy agencies are using in spy satelites to photograph us.
The Final Theory? Sorry to go off topic. That google ad caught my attention. Reminds me of when the B.A. had a psychic ad on his site. Silliness.
The actual exposure time was not 2 hours long. The VLT just spent 2 hours dedicated to Jupiter.
While some things are cleared up it isn’t perfect, so you will have some distortion.
With adaptive optics, the reflector is made up of many mirrors working together to form one large reflector. Each piece is actually making many minor corrections per second to clear up the image. Some software applications can work to smooth the image out more.
The make up of imaging satellites and telescopes are quite different. Imaging satellites don’t require adaptive technology in the same sense; what little is done is often performed my software. They are in low earth orbit so light doesn’t have to travel very far, and the subject is often very well illuminated.
Resolution is much finer with satellites. For spy satellites you are looking at less than one meter per pixel; with digitally converted images from space you are looking at kilometers per pixel.
I do the same thing with my webcam and 12″ Meade.
Ok, just stacked images not the fancy adaptive technology though. Heh!
Nice image though! I’m just amazed with how good these ground-based images are getting. Near Hubble quality!
Tom
Aodhhan Says:
“Would be something to have adaptive optic technology advance to a point where it could be used for 12″+ amateur scopes, and affordable as well.
…dream dream dream!”
Yes! That would give amateur astronomy a incredible push.
As the forces of technology thrive …
I had the same thought as Donut – is the oddness of shape due to the optics, or the equatorial bulge caused by rotation?
Todd and Donut — the oblong shape is due to the fast rotation — the planet is actually larger in diameter through the equator than it is through the poles. The same is true of Earth, but to a much smaller degree.
Not sure the FAA would be too happy to have thousands of powerful lasers pointing into the night’s sky all over the country!
As for more practical amateur techniques, perhaps “lucky imaging” might be something for people with small telescopes to try?
I agree with Andre’s perception. I’m very sure I’ve seen not only better, but interesting images of Jove, adquired by GBT.
vg: Here, some (and some old) from Keck http://astro.berkeley.edu/~imke/JupiterSpots/Keck.htm
and Gemini
http://www.gemini.edu/index.php?q=node/196
And even if they aren’t better, yes Andre, they feel better.
Actually, Hapio, I am British and even though I live in the US, I have no plans for becoming an American citizen. 🙂
But, it it makes you happy, I doubt any national aviation regulator would be happy to have thousands of amateur astronomers pointing industrial strength lasers into the skies over their respective countries. Apparently, the big telescopes that use them have to turn them off when a plane gets too close. That’s workable if you only have a few observatories doing that.
I guess it’s possible that we will find a way to do adaptive optics without needing a laser guide star — we can now to a limited degree, if the target is within a few arc minutes of a bright star — then it will open up to us amateurs.
In the meantime, the “lucky imaging” technique is already being use by some pioneering amateurs, and doesn’t need any extra expensive equipment to use it either.
No worries, just today they were talking about the winners of the baseball playoffs becoming the “World Champions” which still grates with me after years of living here. I guess one club is Canadian, but calling it the “Word Championship” is still a bit of a stretch.
So I understand exactly what you mean.
I love you, VLT.
“# Aodhhan Says:
October 2nd, 2008 at 8:28 am
Would be something to have adaptive optic technology advance to a point where it could be used for 12″+ amateur scopes, and affordable as well.
…dream dream dream!”
>> SBIG’s A0-8 is about as close as we’ll come in the near future, I would imagine. Of course, similar technology will allow this basic design to be improved upon, but I can’t see us getting flexible-mirror peizo-actuator equipped telescopes with laser reference stars in the next 50 years!
I checked the original TIFF image, and I have the feeling I´ve seen better images of Jupiter, from ground based telescopes.
The best amateur photos of Jupiter that I have EVER seen are Damien Peach’s images. Have you seen his work? See here – http://tinyurl.com/4nszjt
I’m still scratching my head trying to figure out his tricks!
Tom
Agreed Tom.It sure makes you wonder what he could accomplish with 2 or 3 times the aperture he has at hand..Truly some awesome imaging.
Clear skies.