寻找月亮

寻找月亮

ByNASA中文

2021年7月11日 Find the Moon Image Credit & Copyright: Jimmy Westlake (Colorado Mountain College) Explanation: Where’s the Moon? Somewhere in this image, the Earth’s Moon is hiding. The entire Moon is visible, in its completely full phase, in plain sight. Even the photographer’s keen eye couldn’t find it even though he knew exactly where to look — only the long exposure of his camera picked it up — barely. Although by now you might be congratulating yourself on finding it, why was it so difficult to see? For one reason, this photograph was taken during a total lunar eclipse, when the Earth’s shadow made the Moon much dimmer than a normal full Moon. For another, the image, taken in Colorado, USA, was captured just before sunrise….

两个半球的夜空

两个半球的夜空

ByNASA中文

2020 February 27 Two Hemisphere Night Sky Image Credit & Copyright: Petr Horálek/ESO, Juan Carlos Casado/IAC (TWAN) Explanation: The Sun is hidden by a horizon that runs across the middle in this two hemisphere view of Earth’s night sky. The digitally stitched mosaics were recorded from corresponding latitudes, one 29 degrees north and one 29 degrees south of the planet’s equator. On top is the northern view from the IAC observatory at La Palma taken in February 2020. Below is a well-matched southern scene from the ESO La Silla Observatory recorded in April 2016. In this projection, the Milky Way runs almost vertically above and below the horizon. Its dark clouds and and bright nebulae are prominent near the galactic center in the lower half…