Over 4000 planets are now known to exist outside our Solar System. Known as exoplanets, this milestone was passed last month, as recorded by NASA's Exoplanet Archive. The featured video highlights these exoplanets in sound and light, starting chronologically from the first confirmed detection in 1992.

SNR 0104 is a supernova remnant with an unusual shape. Found 190,000 light-years away in our neighboring galaxy the Small Magellanic Cloud, SNR 0104 is suspected of being the expanding debris cloud from a Type 1a supernova - the catastrophic thermonuclear explosion of a white dwarf star.

Where else might life exist? One of humanity's great outstanding questions, locating planets where extrasolar life might survive took a step forward in 2019 with the discovery of a significant amount of water vapor in the atmosphere of distant exoplanet K2-18b.