Laser trial run kickstarts new era of interferometry

Four lasers were projected into the skies above the European Southern Observatory’s (ESO’s) Paranal site in Chile. The lasers are each used to create an artificial star, which astronomers use to measure and then correct the blur caused by Earth's atmosphere. The striking launch of these lasers, one from each of the eight-metre telescopes at Paranal, is a significant milestone of the GRAVITY+ project — a large and complex upgrade to ESO’s Very Large Telescope Interferometer (VLTI). GRAVITY+ unlocks a greater observing power and a much wider sky coverage for the VLTI than previously possible.