ATLAS survey

ATLAS (for Asteroid Terrestrial-impact Last Alert System) is a NASA-funded survey to warn of impending impacts by asteroids (near-Earth objects, i.e., NEOs). Observations are carried out on four dedicated 0.5-m telescopes: two in Hawaii (ATLAS-MLO at Mauna Loa and ATLAS-HKO at the Haleakala Observatory), one at South African Astronomical Observatory (SAAO), and one at El Sauce Observatory in Chile. The four cover the whole sky, with double coverage for a portion. The cadence is much shorter than that of Pan-STARRS, to increase the chance of spotting any impending impact. The survey began operation with one telescope in 2015, subsequently expanded to the four. In addition to minor planets, it has discovered other transients such as supernovae.