流星与对日照
2021年05月12日 A Meteor and the Gegenschein Image Credit: J.C. Casado, StarryEarth, EELabs, TWAN Explanation: Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for “counter glow”) can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles. These dust particles are millimeter sized splinters from asteroids and orbit in the ecliptic plane of the planets. Pictured here from last March is one of the more spectacular pictures of the gegenschein yet taken. The deep exposure of an extremely dark sky over Teide Observatory in Spain’s Canary Islands shows the gegenschein as part of extended zodiacal light. Notable…