双子座流星

双子座流星

2022年12月16日 The Geminid Image Credit & Copyright: Jeff Dai (TWAN) Explanation: Returning from beyond the Moon, on December 11 the Orion spacecraft entered Earth’s atmosphere at almost 11 kilometers per second. That’s half the speed of the grain of dust that created this long fireball meteor when it entered the atmosphere on December 13, near the peak of the annual Geminid meteor shower. As our fair planet makes its yearly pass through the dust trail of mysterious asteroid 3200 Phaethon, the parallel tracks of all Geminid meteors appear to radiate from a point in the constellation Gemini. But the twin stars of Gemini hide just behind the trees on the left in this night skyscape from the beautiful Blue Moon Valley, Yunnan, China. Reflected in…

双子流星雨

双子流星雨

2021年11月16日 Geminids from Gemini Image Credit & Copyright: Wang Jin Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Gemini. That is why the major meteor shower in December is known as the Geminids — because shower meteors all appear to come from a radiant toward Gemini. Three dimensionally, however, sand-sized debris expelled from the unusual asteroid 3200 Phaethon follows a well-defined orbit about our Sun, and the part of the orbit that approaches Earth is superposed in front of the constellation of Gemini. Therefore, when Earth crosses this orbit, the radiant point of falling debris appears in Gemini. Featured here, a composite of many images taken during the 2020 Geminids…

双子流星

双子流星

2020年12月17日 Gemini’s Meteors Image Credit & Copyright: Stefano Pellegrini Explanation: Taken over the course of an hour shortly after local midnight on December 13, 35 exposures were used to create this postcard from Earth. The composited night scene spans dark skies above the snowy Italian Dolomites during our fair planet’s annual Geminid meteor shower. Sirius, alpha star of Canis Major and the brightest star in the night, is grazed by a meteor streak on the right. The Praesepe star cluster, also known as M44 or the Beehive cluster, itself contains about a thousand stars but appears as a smudge of light far above the southern alpine peaks near the top. The shower’s radiant is off the top of the frame though, near Castor and Pollux…

兴隆观测站上空的双子流星

兴隆观测站上空的双子流星

2020年12月13日 Geminid Meteors over Xinglong Observatory Image Credit & Copyright: Steed Yu and NightChina.net Explanation: Where do Geminid meteors come from? In terms of location on the sky, as the featured image composite beautifully demonstrates, the sand-sized bits of rock that create the streaks of the Geminids meteor shower appear to flow out from the constellation of Gemini. In terms of parent body, Solar System trajectories point to the asteroid 3200 Phaethon — but this results in a bit of a mystery since that unusual object appears mostly dormant. Perhaps, 3200 Phaethon undergoes greater dust-liberating events than we know. Over 50 meteors including a bright fireball were captured during the peak of the 2015 Geminids Meteor Shower streaking above Xinglong Observatory in China. The Geminids…