Copyright:
Sean M. Sabatini
原文:
There was a shower over Monument Valley — but not water. Meteors. The featured image — actually a composite of six exposures of about 30 seconds each — was taken in 2001, a year when there was a very active Leonids shower. At that time, Earth was moving through a particularly dense swarm of sand-sized debris from Comet Tempel-Tuttle, so that meteor rates approached one visible streak per second. The meteors appear parallel because they all fall to Earth from the meteor shower radiant — a point on the sky towards the constellation of the Lion (Leo). The yearly Leonids meteor shower peaks again this week. Although the Moon’s glow should not obstruct the visibility of many meteors, this year’s shower will peak with perhaps 15 meteors visible in an hour, a rate which is good but not expected to rival the 2001 Leonids. By the way — how many meteors can you identify in the featured image?
中文翻譯:
在紀念谷上方發生了一場流星雨——不過不是水，而是流星。這幅特別的圖像——實際上是六幅約30秒的曝光合成而成——拍攝於2001年，那是一個流星雨活躍的年份。當年，地球正好穿越了彗星Tempel-Tuttle釋放的密集沙粒大小的塵埃雲，流星的出現率達到每秒一條可見的流星。流星之所以看起來是平行的，是因為它們都是從流星雨的輻射點——在天空中朝向獅子座（Leo）的方向落向地球。今年的年度獵戶座流星雨將在這一週達到極點。儘管月光不會對許多流星的能見度造成太大妨礙，但今年的流星雨預計每小時可見約15顆流星，這個速度不錯，但與2001年的獵戶座流星雨相比尚有距離。對了，你能在這幅特別的圖像中識別出多少顆流星呢？
#流星雨 #獵戶座流星雨 #紀念谷 #夜空奇觀 #攝影 #宇宙奇跡 #流星 #觀星 #天文學
來源:NASA每日圖片
