金星的位相

金星的位相

2024年1月8日 The Phases of Venus Image Credit & License: Stéphane Gonzales Explanation: Venus goes through phases. Just like our Moon, Venus can appear as a full circular disk, a thin crescent, or anything in between. Venus, frequently the brightest object in the post-sunset or pre-sunrise sky, appears so small, however, that it usually requires binoculars or a small telescope to clearly see its current phase. The featured time-lapse sequence was taken over the course of six months in 2015 from Surgères, Charente-Maritime, France, and shows not only how Venus changes phase, but changes angular size as well. When Venus is on the far side of the Sun from the Earth, it appears angularly smallest and nearest to full phase, while when Venus and Earth are…

阿波罗17号影像: 蛾眉相的地球

阿波罗17号影像: 蛾眉相的地球

2023年5月13日 Apollo 17: The Crescent Earth Image Credit: Apollo 17, NASA; Restoration – Toby Ord Explanation: Our fair planet sports a curved, sunlit crescent against the black backdrop of space in this stunning photograph. From the unfamiliar perspective, the Earth is small and, like a telescopic image of a distant planet, the entire horizon is completely within the field of view. Enjoyed by crews on board the International Space Station, only much closer views of the planet are possible from low Earth orbit. Orbiting the planet once every 90 minutes, a spectacle of clouds, oceans, and continents scrolls beneath them with the partial arc of the planet’s edge in the distance. But this digitally restored image presents a view so far only achieved by 24…

寻找新月

寻找新月

2022年7月25日 Find the New Moon Image Credit & Copyright: Mohamad Soltanolkotabi Explanation: Can you find the Moon? This usually simple task can be quite difficult. Even though the Moon is above your horizon half of the time, its phase can be anything from crescent to full. The featured image was taken in late May from Sant Martí d’Empúries, Spain, over the Mediterranean Sea in the early morning. One reason you can’t find this moon is because it is very near to its new phase, when very little of the half illuminated by the Sun is visible to the Earth. Another reason is because this moon is near the horizon and so seen through a long path of Earth’s atmosphere — a path which dims the…

金星与月亮

金星与月亮

2022年2月3日 Embraced by Sunlight Image Credit & Copyright: Juan Luis Cánovas Pérez Explanation: Even though Venus (left) was the brightest planet in the sky it was less than 1/30th the apparent size of the Moon on January 29. But as both rose before the Sun they shared a crescent phase. For a moment their visible disks were each about 12 percent illuminated as they stood above the southeastern horizon. The similar sunlit crescents were captured in these two separate images. Made at different magnifications, each panel is a composite of stacked video frames taken with a small telescope. Venus goes through a range of phases like the Moon as the inner planet wanders from evening sky to morning sky and back again with a period…

即将卸任昏星的金星

即将卸任昏星的金星

2022年1月6日 The Last Days of Venus as the Evening Star Image Credit & Copyright: Tamas Ladanyi (TWAN) Explanation: That’s not a young crescent Moon posing behind cathedral towers after sunset. It’s Venus in a crescent phase. About 40 million kilometers away and about 2 percent illuminated by sunlight, it was captured with camera and telephoto lens in this series of exposures as it set in western skies on January 1 from Veszprem, Hungary. The bright celestial beacon was languishing in the evening twilight, its days as the Evening Star coming to a close as 2022 began. But it was also growing larger in apparent size and becoming an ever thinner crescent in telescopic views. Heading toward a (non-judgemental) inferior conjunction, the inner planet will be…

阿波罗17号:蛾眉相的地球

阿波罗17号:蛾眉相的地球

2021年04月29日 Apollo 17: The Crescent Earth Image Credit: Apollo 17, NASA; Restoration – Toby Ord Explanation: Our fair planet sports a curved, sunlit crescent against the black backdrop of space in this stunning photograph. From the unfamiliar perspective, the Earth is small and, like a telescopic image of a distant planet, the entire horizon is completely within the field of view. Enjoyed by crews on board the International Space Station, only much closer views of the planet are possible from low Earth orbit. Orbiting the planet once every 90 minutes, a spectacle of clouds, oceans, and continents scrolls beneath them with the partial arc of the planet’s edge in the distance. But this digitally restored image presents a view so far only achieved by 24…