Happy “Star Wars Day” from PhysicsCentral! In a case of seriously excellent timing, the European Southern Observatory recently released a photo of their telescope being calibrated. Is it just us, or does it look suspiciously familiar?
|At the ESO’s Panaral observatory, powerful lasers are used to create an artificial “star” in the upper atmosphere, to help calibrate a telescope’s optical systems.
Image Credit: F. Kamphues, ESO.
While it certainly looks like the primary firing sequence of a Death Star, this array of four lasers is no weapon. Focused at a point high up in the atmosphere, it creates a hot region of ionized sodium atoms, which give off light of their own. The artificial “star” created by this process—known as a laser guide star
—is used to calibrate telescopes like the Very Large Telescope
by allowing astronomers to correct for distortions caused by Earth’s atmosphere.