Mercury’s dark, barely reflective surface has long been a mystery to scientists. Now, researchers believe that a steady rain of carbon over billions of years from comets crumbling near the Sun has coated the innermost planet.
Astronomers using large telescopes in South Africa and Chile identify the closest known flyby of a star to our Solar System: a low-mass star system nicknamed “Scholz’s Star” that passed through the Oort Cloud 70,000 years ago.