Από την/τον Christina Politi | 26 Αυγούστου 2013
Astronomers have built a new astro-camera that, when fitted onto the largest observatories on Earth, can snap photos of the universe twice as sharp as the famed Hubble Space Telescope.
With the newly developed technology, giant telescopes can reach their theoretical limits of resolution in visible light —something that was just not possible, until now, because of atmospheric turbulence causing blurry visible light images. (Related: The Largest Baby Star, Ever?)
“It was very exciting to see this new camera make the night sky look sharper than has ever before been possible,” said Laird Close, the project’s principal scientist at the University of Arizona in a press statement.
Called Adaptive Secondary Mirror (ASM), this new imaging technology sits high above the primary mirror of the telescope, working to counter the atmospheric turbulence by changing the shape of its thin curved glass mirror 1,000 times each second.
“As a result, we can see the visible sky more clearly than ever before,” said Close. “It’s almost like having a telescope with a 21-foot mirror in space.”
The Magellan Telescope with MagAO’s Adaptive Secondary Mirror (ASM) mounted at the top looking down some 30 feet onto the 21-foot diameter primary mirror, which is encased inside the blue mirror cell. Credit: Yuri Beletsky, Las Campanas Observatory
The new imaging package called MagAO (Magellan Adaptive Optics) takes its name from the Magellan 6.5 meter (21 foot) telescope in Chile’s high desert, which has been snapping some pretty stunning images of the Orion nebula. (Related: “Most Massive Star Discovered—Shatters Record.”)
As an initial test of the new camera system, astronomers looked to see if they could split a very tight binary star system buried inside the giant gas cloud. Called Theta 1 Ori C, the two stars are about the same distance from each other as Earth is from planet Uranus.
The power of visible light adaptive optics: On the left is a “normal” photo of the theta 1 Ori C binary star in red light. The middle image shows the same object, but with MagAO’s adaptive optics system turned on. Eliminating the atmospheric blurring, the resulting photo becomes about 17 times sharper, turning a blob into a crisp image of a binary star pair. These are the highest resolution photos taken by a telescope. Credit: Laird Close/UA
“I have been imaging Theta 1 Ori C for more than 20 years and never could directly see that it was in fact two stars,” Close said. “But as soon as we turned on the MagAO system, it was beautifully split into two stars.”
The new photos also reveal surprising details of dust formations associated with the beginnings of planetary systems around the stars. Never-before-seen teardrop shaped clouds carved by strong radiation winds emitted from the baby stars.
“It is important to understand how dust is laid out in these objects because that dust and gas is what nature uses to build planets,” Close explained. “Our new imaging capabilities revealed there is very little dust and gas in the outer part of the disk.”
Posted by Andrew Fazekas in StarStruck