Astronomy Picture of the Day——哈雷彗星的尘埃与银河
Halley Dust and Milky Way
Image Credit & Copyright: Gang Li
Explanation: Grains of cosmic dust streakedthrough the mostly moonless night skies of May 7. Swept up as planet Earthplowed through the debris streams left behind by periodic Comet Halley, theannual meteor shower is known as the Eta Aquarids. Though it was made about aday after the shower's predicted maximum, this composite image still captures20 meteors in exposures taken over a 2 hour period, registered on a backgroundexposure of the sky. The meteor trails point back to the shower radiant neareponymous faint star Eta Aquarii close to the horizon, seen from 100 kilometerssouth of Sydney Australia. Known for speed, Eta Aquarid meteors move fast,entering the atmosphere at about 66 kilometers per second. Brilliant Jupitershines near the central bulge of the Milky Way high above the horizon. TheSouthern Cross is just tucked in to the upper right corner of the frame.
哈雷彗星的尘埃与银河
5月7日，宇宙尘埃颗粒划过了几乎没有月光的夜空。地球在哈雷彗星遗留的碎片流中穿过，这个一年一度的流星雨被称为宝瓶座η流星雨。虽然这幅合成图像是在流星雨达到极大期后一天拍摄到的，但是它仍在2个小时内捕捉到了20颗流星，并呈现在以天空为背景的曝光图像中。从澳大利亚悉尼以南100公里处看去，流星余迹指向的辐射点靠近地平线，是与流星雨同名的暗星宝瓶座η星。以速度著称的宝瓶η流星移动速度极快，可达每秒66公里。明亮的木星在地平线上空、银河系的中央凸起处闪耀，而南十字恰好位于图像的右上角。
参考文献：
https://apod.nasa.gov/apod/image/1905/eta_aquarids_Gang.jpg
近期文章：
Astronomy Picture of the Day——梅西耶第五天体