Straight to the Milky Way's heart

The Laser Guide Star (LGS) is launched from the VLT's 8.2-metre Yepun Telescope and aims at the centre of our galaxy, in the heart of the brightest part of the Milky Way. The laser beam is part of the VLT's adaptive optics system. It creates an artificial star at 90 km altitude in the Earth´s mesosphere. This star is used as reference to correct images and spectra for the blurring effect of the atmosphere. The plane of the Milky Way is crossed by prominent dark lanes, huge clouds of interstellar dust that block the visible light. Thanks to the infrared instruments mounted in the Yepun Telescope, astronomers can “see through” and study the complex and turbulent core of our galaxy, where a supermassive black hole is lurking. The ESO's Very Large Telescope is composed by four 8.2-metre Unit Telescopes (UTs, where Yepun is UT4) plus four 1.8-metre movable Auxiliary Telescopes (ATs).