太空站、日珥与太阳

2021年05月04日

Space Station, Solar Prominences, Sun
Image Credit & Copyright: Mehmet Ergün

Explanation: That’s no sunspot. It’s the International Space Station (ISS) caught passing in front of the Sun. Sunspots, individually, have a dark central umbra, a lighter surrounding penumbra, and no Dragon capsules attached. By contrast, the ISS is a complex and multi-spired mechanism, one of the largest and most complicated spacecraft ever created by humanity. Also, sunspots circle the Sun, whereas the ISS orbits the Earth. Transiting the Sun is not very unusual for the ISS, which orbits the Earth about every 90 minutes, but getting one’s location, timing and equipment just right for a great image is rare. The featured picture combined three images all taken from the same location and at nearly the same time. One image — overexposed — captured the faint prominences seen across the top of the Sun, a second image — underexposed — captured the complex texture of the Sun’s chromosphere, while the third image — the hardest to get — captured the space station as it shot across the Sun in a fraction of a second. Close inspection of the space station’s silhouette even reveals a docked Dragon Crew capsule.

Tomorrow’s picture: all sky STEVE

太空站、日珥与太阳
影像提供与版权: Mehmet Ergün

说明: 那不是太阳黑子，而是凌越太阳前方的国际太空站（ISS）。因为，太阳黑子有黝黑的中心本影，周围环拱着较淡的半影，而且不会有定泊在旁的飞龙号模组舱。此外，ISS有槎桠的多重结构，是人类至今建造过最大最复杂的太空船。还有，太阳黑子环绕太阳，国际太空站则绕行地球。国际太空站每90分钟绕行地球一圈，所以太空站凌日是相对常见的景观，不过要精确掌握它凌日的位置和时机，并拍下精采的影像难度不低。这幅主题影像，整合了3张摄于相同地点和取像时间几乎相同的照片。其中一张过曝，以记录太阳盘面上缘的昏暗日珥。另一张曝光不足，以拍下太阳色球层复杂的纹理。最后一张照片的难度最高，必须在国际太空站掠过日盘的转瞬间捕捉到它的身影。如仔细检视国际太空站的剪影，可发现停泊在该处的飞龙号载人模组舱。

明日的图片: all sky STEVE