Astronomy Picture of the Day——拉帕尔马上空的流星、彗星和北斗七星
Meteors, Comet, and Big Dipper over LaPalma
Image Credit & Copyright: VincentDuparc
Explanation: Meteor showers are caused bystreams of solid particles, dust size and larger, moving as a group throughspace. In most cases, the orbits of these meteor streams can be identified withdust expelled from a comet. When the Earth passes through a stream, theparticles leave brilliant trails through the night sky as they disintegrate inEarth\\\'s atmosphere. The meteor paths are all parallel to each other, but, liketrain tracks, the effect of perspective causes them to appear to originate froma radiant point in the distance. The featured image composite was taken duringJanuary\\\'s Quadrantid meteor shower from La Palma, one of Spain\\\'s CanaryIslands, off the northwest coast of Africa. The Quadrantids radiant is visiblejust below the handle of the Big Dipper. A careful eye will also discern thefaint green coma of Comet Wirtanen. Tonight is the peak of the modest Lyridmeteor shower, with several meteors per hour visible from dark locations withclear skies.
拉帕尔马上空的流星、彗星和北斗七星
流星雨是由固体的颗粒流引起的，成群的尘埃般大小的颗粒在太空中移动。在大多情况下，流星群的轨道可以通过彗星释放的尘埃来确定。当地球穿过流星群时，这些颗粒在地球大气中燃烧，它们会在夜空中留下明亮的流星余迹。流星的轨迹都是平行的，就像火车轨道一样，视觉上感觉它们好像来源于一个远处的辐射点。这幅合成的特征图片拍摄于一月份象限仪座流星雨期间，地点是位于非洲西北海岸外的西班牙拉帕尔马。象限仪座流星雨的辐射点在北斗七星勺柄下方可见。仔细观察还会发现维尔塔宁彗星的黯淡绿色彗发。今晚是美丽的天琴座流星雨极大期，从黑暗宽敞的地方、晴朗天空中每小时可以看到数颗流星。
原图地址：
https://apod.nasa.gov/apod/image/1904/Quadrantids_Duparc_1830.jpg
近期文章：
Astronomy Picture of the Day——火星上甲烷深藏的秘密