OUR GALAXY

Laser images of Milky Way centre

UCLA astronomers and colleagues have taken the first clear picture of the center of our Milky Way galaxy, including the area surrounding the supermassive black hole, using a new laser virtual star at the W.M. Keck observatory in Hawaii.
"Everything is much clearer now," said Andrea Ghez, UCLA professor of physics and astronomy, who headed the research team. "We used a laser to improve the telescope's vision — a spectacular breakthrough that will help us understand the black hole's environment and physics."
Astronomers are used to working with images that are blurred by the Earth's atmosphere. However, a laser virtual star, launched from the Keck telescope, can be used to correct the atmosphere's distortions and clear up the picture.
This new technology, called Laser Guide Star adaptive optics, will lead to important advances for the study of planets in our solar system and outside of our solar system, as well as galaxies, black holes, and how the universe formed and evolved, Ghez said.
"We have worked for years on techniques for 'beating the distortions in the atmosphere' and producing high-resolution images," she said.

[Ghez and her colleagues took "snapshots" of the center of the galaxy, targeting the supermassive black hole 26,000 light years away, at different wavelengths. This approach allowed them to study the infrared light emanating from very hot material just outside the black hole's "event horizon," about to be pulled through.]