保护地球，探索宇宙，发现文明
2024年1月13日 Circling the Sun Image Credit & Copyright: Radoslav Zboran Explanation: Earth’s orbit around the Sun is not a circle, it’s an ellipse. The point along its elliptical orbit where our fair planet is closest to the Sun is called perihelion. This year, perihelion was on January 2 at 01:00 UTC, with the Earth about 3 million miles close...
2021年12月28日 Sun Halo over Sweden Video Credit & Copyright: Håkan Hammar (Vemdalen Ski Resort, SkiStar) Explanation: What’s happened to the Sun? Sometimes it looks like the Sun is being viewed through a giant lens. In the featured video, however, there are actually millions of tiny lenses: ice crystals. Water may freeze in the atmosphere into small...
2021年06月10日 Circular Sun Halo Image Credit & Copyright: Vincenzo Mirabella Explanation: Want to see a ring around the Sun? It’s easy to do in daytime skies around the world. Created by randomly oriented ice crystals in thin high cirrus clouds, circular 22 degree halos are visible much more often than rainbows. This one was captured by smart phone ...