![ESO on Twitter: "@IDLofficial 7/ ESO's #VLT has a cutting-edge Laser Guide Star Facility (4LGSF), that produce four artificial stars by exciting sodium atoms at an altitude of 90 km. Read more ESO on Twitter: "@IDLofficial 7/ ESO's #VLT has a cutting-edge Laser Guide Star Facility (4LGSF), that produce four artificial stars by exciting sodium atoms at an altitude of 90 km. Read more](https://pbs.twimg.com/media/FwPPW3CX0AE5Oth.jpg:large)
ESO on Twitter: "@IDLofficial 7/ ESO's #VLT has a cutting-edge Laser Guide Star Facility (4LGSF), that produce four artificial stars by exciting sodium atoms at an altitude of 90 km. Read more
![From ESO: “Active Optics – Inventing a game changer” Nothing Really New, but Important Thanks to ESO | sciencesprings From ESO: “Active Optics – Inventing a game changer” Nothing Really New, but Important Thanks to ESO | sciencesprings](https://i0.wp.com/cdn.eso.org/images/screen/eso9940b.jpg)
From ESO: “Active Optics – Inventing a game changer” Nothing Really New, but Important Thanks to ESO | sciencesprings
![ESO on Twitter: "ESO's #VLT counteracts the blurriness of stars caused by the atmosphere through use of the 4 Laser Guide Star Facility (4LGSF), which creates artificial stars acting as reference points ESO on Twitter: "ESO's #VLT counteracts the blurriness of stars caused by the atmosphere through use of the 4 Laser Guide Star Facility (4LGSF), which creates artificial stars acting as reference points](https://pbs.twimg.com/media/EAgQfC8W4AI2AYj.jpg:large)