60秒后的绿闪日落

60秒后的绿闪日落

ByNASA中文

2023年10月25日 Gone in 60 Seconds: A Green Flash Sunset Video Credit & Copyright: Tengyu Cai Explanation: In 60 seconds, this setting Sun will turn green. Actually, the top of the Sun already appears not only green, but wavey — along with all of its edges. The Sun itself is unchanged — both effects are caused by looking along hot and cold layers in Earth’s atmosphere. The unusual color is known as a green flash and occurs because these atmospheric layers not only shift background images but disperse colors into slightly different directions, like a prism. The featured video was captured earlier this month off the coast of Hawaii, USA. After waiting those 60 seconds, at the video’s end, the upper part of the Sun seems…

落日的多重绿闪

落日的多重绿闪

ByNASA中文

2023年3月28日 A Multiple Green Flash Sunset Image Credit & Copyright: T. Slovinský & P. Horálek (IoP Opava); CTIO, NOIRLab, NSF, AURA Explanation: Yes, but can your green flash do this? A green flash at sunset is a rare event that many Sun watchers pride themselves on having seen. Once thought to be a myth, a green flash is now understood to occur when the Earth’s atmosphere acts like both a prism and a lens. Different atmospheric layers create altitude-variable refraction that takes light from the top of the Sun and disperses its colors, creates two images, and magnifies it in just the right way to make a thin sliver appear green just before it disappears. Pictured, though, is an even more unusual sunset. From the…

太阳绿闪的影片

太阳绿闪的影片

ByNASA中文

2021年11月10日 Video of a Green Flash Video Credit & Copyright: Paolo Lazzarotti Explanation: Many think it is just a myth. Others think it is true but its cause isn’t known. Adventurers pride themselves on having seen it. It’s a green flash from the Sun. The truth is the green flash does exist and its cause is well understood. Just as the setting Sun disappears completely from view, a last glimmer appears startlingly green. The effect is typically visible only from locations with a low, distant horizon, and lasts just a few seconds. A green flash is also visible for a rising Sun, but takes better timing to spot. A dramatic green flash was caught on video last month as the Sun set beyond the Ligurian…

太阳、月亮、金星及水星的绿闪

太阳、月亮、金星及水星的绿闪

ByNASA中文

2020 May 30 Green Flashes: Sun, Moon, Venus, Mercury Image Credit & Copyright: Marcella Giulia Pace Explanation: Follow a sunset on a clear day against a distant horizon and you might glimpse green just as the Sun disappears from view. The green flash is caused by refraction of light rays traveling to the eye over a long path through the atmosphere. Shorter wavelengths refract more strongly than longer redder wavelengths and the separation of colors lends a green hue to the last visible vestige of the solar disk. It’s harder to see a green flash from the Moon, not to mention the diminutive disks of Venus and Mercury. But a telescope or telephoto lens and camera can help catch this tantalizing result of atmospheric refraction…