万圣节与鬼头星云

2021年10月24日

Halloween and the Ghost Head Nebula
Image Credit: Mohammad Heydari-Malayeri (Observatoire de Paris) et al., ESA, NASA

Explanation: Halloween’s origin is ancient and astronomical. Since the fifth century BC, Halloween has been celebrated as a cross-quarter day, a day halfway between an equinox (equal day / equal night) and a solstice (minimum day / maximum night in the northern hemisphere). With a modern calendar however, even though Halloween occurs next week, the real cross-quarter day will occur the week after. Another cross-quarter day is Groundhog Day. Halloween’s modern celebration retains historic roots in dressing to scare away the spirits of the dead. Perhaps a fitting tribute to this ancient holiday is this view of the Ghost Head Nebula taken with the Hubble Space Telescope. Similar to the icon of a fictional ghost, NGC 2080 is actually a star forming region in the Large Magellanic Cloud, a satellite galaxy of our own Milky Way Galaxy. The Ghost Head Nebula (NGC 2080) spans about 50 light-years and is shown in representative colors.

Tomorrow’s picture: highway to hole

万圣节与鬼头星云
影像提供: Mohammad Heydari-Malayeri (Observatoire de Paris) et al., ESA, NASA

说明: 万圣节的起源很古老而且和天文学有关。从西元前五世纪起，万圣节是越区节的一个庆典，这种节日恰好介于北半球日夜等长的春/秋分，以及昼夜差异最大的夏/冬至之间。不过在现代历法里，纵然万圣节是在下星期，但真正的越区节则是要再晚一星期。对了，另一个越区节是土拨鼠 日。现代庆祝万圣节的服饰，是另一项古代遗留下来的习俗，目的在于吓走在人间游荡的鬼魂。所以上面这张由哈伯太空望远镜所拍摄的鬼头星云影像，对这个古老节日是一项很适当的献礼。外观上很像个虚构鬼魂图案的NGC 2080，实际上是个位在我们银河系伴星系─大麦哲伦星系之内的恒星形成区。上面这幅代表色影像所呈现的鬼头星云（NGC 2080），大小约有50光年。

明日的图片: highway to hole