January 10, 2013
Gemini Observatory Has New Instrument To Study Universe With Such Clarity, Detail
redOrbit Staff & Wire Reports - Your Universe Online
Researchers at the Gemini Observatory in Chile are touting a new instrument that they claim will allow astronomers to “study the universe with an unprecedented level of clarity and detail.”
The system is called GeMS, and it is an advanced adaptive optics system that has been installed on the Gemini South telescope. According to a statement released by representatives of the facility on Wednesday, it is the first instrument of its kind “to use laser guide stars and a technology called Multi-Conjugate Adaptive Optics (MCAO) to image the sky.”
To demonstrate their point, the observatory released a new image of the outskirts of the Orion Nebula, captured at night last December 28. The picture provides a field-of-view that is 85 arcseconds across that “demonstrates the system's extreme resolution and uniform correction across the entire field.”
Three filters were used for the image — [Fe II] for the blue layer, H2 for the orange layer, and K(short)-continuum (2.093 microns) for the white layer. Each filter had a total exposure of 600 seconds, they added.
So how does it work? According to the observatory, the MCAO currently installed in the GeMS system used five laser guide stars and three deformable mirrors to sample atmospheric distortions and then cancel them out instantly while imaging data is being collected. It uses algorithms similar in nature to those used for medical tomographic imaging to create a 3D snapshot of atmospheric turbulence up to 1000 times per second, which results in a 16-fold increase in the amount of area that can be observed or photographed by the telescope.
"The combination of a constellation of five laser guide stars with multiple deformable mirrors allows us to expand significantly on what has previously been possible using adaptive optics in astronomy," Benoit Neichel, the head of Gemini´s adaptive optics program, said in a statement.
Former Gemini scientist FranÃ§ois Rigaut, who originally came up with the idea for the GeMS system before departing the team for the Australian National University, said that is was “a great feeling to see this system on the sky and doing cutting-edge science. When it's all theoretical you dream of what it will someday do to improve our vision of the cosmos. An image like this makes it so real — it´s worth all the mental sweat!"
The advances with the Gemini South telescope could also be good news for future ground-based observatories, such as the 30-Meter Telescope (TMT) Project. TMT Project Manager Gary Sanders said that the MCAO “makes the next generation of large telescopes“¦ justifiable,” because it shows researchers how to use collected light more efficiently and avoid distortions caused by air turbulence.