“Lucky Camera” takes sharpest ever images of stars
A team of astronomers have taken pictures of the stars that are sharper than anything produced by the Hubble telescope, at 50 thousandths of the cost.
The researchers, from the University of Cambridge and the California Institute of Technology (Caltech), used a technique called “Lucky Imaging” to take the most detailed pictures of stars and nebulae ever produced – using a camera based on the ground.
Images from ground-based telescopes are usually blurred by the Earth’s atmosphere – the same effect that makes the stars appear to twinkle when we look at them with the naked eye.
The Cambridge/Caltech team, however, surpassed the quality of images taken from space by using a high-speed camera to take numerous images of the same stars at a rate of 20 frames per second. Because of fluctuations in the atmosphere, some of these were less smeared than others. The team then used computer software to choose the best images, and these were combined to create pictures far sharper than anything that has been taken from space.
I thought such procedures were “standard?” Must have been an early edition of Science Today I read about it==along with all those micromirror focus mirrors that can change angles based upon the “twinkle?” Expect sharper pictures from that when these two techniques are combines.
Interesting that this technique would “not work” with Hubble as that is limited by optics instead of interference??
Hooray for ground based cheap/intelligent science. Means more (other) things can be done.
#1, Bobbo, Hooray for ground based cheap/intelligent science. Means more (other) things can be done.
This is only good for visible light. Other spectra still require orbital scopes or probes, as the Earth’s atmosphere severely attenuates infrared and freqs. ultraviolet and above.
Solar research, so important today with the global warming questions, requires capturing data in all wavelengths for which we can design instruments. Here’s one of the best set of probes in service:
http://stereo.jhuapl.edu/
I read this same story with the opposite slant. The adaptive optics photos were crap compared to the Hubble stuff.
Oh I see #3 beat me to it. Hubble FTW!
And just to totally monopolize this thread, take at look at the Picture Of The Day here, taken with a small 10 inch catadioptric scope using some amazing imaging technology:
http://tinyurl.com/22bsjw
Well worth a look!
2==Bubba, THATS the other stuff!! But yeah, optical viewing is a small part of program and I wasn’t thinking of the other stuff to be honest.
Still highlights though being “thoughtful” on how to spend the money? Should optics be put into space if way cheaper technology can do it earth bound? Theres always a lag time before such things are “accepted.”
This technique may produce superior narrow field images of stars, but Hubble is still the best for wide field images. Compare the images above of the Cat’s Eye Nebula with Hubble’s ’94 image:
Hubble Cat’s Eye
Sorry, I see others posted the image already. It would be nice if there were a preview function that also prints the latest comments. A number of blogging and bulletin board sites have this ability. That way you can withdraw a comment if it’s redundant.
#7, Bobbo, so far, even with the projected results expected from the VLTI and other earth based optical scopes there is no substitute for space-based instrumentation. The earth-based instruments are useful in many, many areas, but can’t compete with results from Hubble, Spitzer, STEREO, et al.
Many areas of research today are extremely time-constrained (gamma ray bursts, supernovae, etc.), and on Earth, when you’re “rained out”, your grant money disappears and there are no second chances. And I’ve found it’s difficult to observe the Sun with the McMath – Pierce scope at midnight.
That said, it sure is a lot easier to travel to Hawaii or Cerro Tololo to fix scope problems when they occur.
Hubble just lost another gyroscope in the last few days
Amateur astronomers have been doing this for years with digital cameras and Photoshop. Meh.
The question lurking in this layman’s mind is that with all the computer/optical massaging of the data just exactly where is the true image? Digital data is just that, and how do we know that the beautiful image we see with all the swirling colors are anywhere close to the actual shape or appearance of the celestial object? And anyway, all the light we receive from the deep cosmos is so twenty billion years ago, anyway.
#12, Omar, here’s a good explanation of how color is used with the Hubble. Visible light photos are often processed to enhance detail, but with spectra beyond the eye’s ability to process, false color is mandatory. Too bad we can’t see infrared and ultraviolet.
NASA official Hubble site:
http://tinyurl.com/2cvwf2
Can you imagine if we could see the EM spectrum in the radio or microwave bands? Your house would never be dark if you live in a city!
The “Let’s grab 20 frames/second” only works if you have enough light.
In Astronomy, a long exposure time is where you get to see the things that are really faint. Another way you can be photon limited is if you only want to look at a certain wavelength, or you only want to look at polarized light. To have a long exposure on Earth, you have to have Adaptive Optics (where you are moving parts of the mirrors around to correct for the atmosphere).
One huge advantage for Hubble that is often over looked is that it can stare at the same point for days or weeks. On Earth, because of the rotation, we can’t do that. This is what gives us some of the Deep field images, where you get to see hundreds of galaxies.
#11 – john
“Amateur astronomers have been doing this for years with digital cameras and Photoshop. Meh.”
So much for the wonders of the universe! Anything smaller and more insignificant you’re not impressed with experiencing? Well, probably this post – but other than this post?
#1 Bobbo:
The mirror technique you mentioned is called active optics. Adaptive optics, which was combined with lucky imaging, as opposed to speckle imaging in the past, was used in this recent experiment.
#11 – john –
Amateurs have been working with the shift and add speckle imaging method for years using webcams. Lucky imaging requires a much higher speed camera.