木卫二

木卫二

2023年5月20日 Galileo’s Europa Image Credit: NASA, JPL-Caltech, SETI Institute, Cynthia Phillips, Marty Valenti Explanation: Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon’s icy surface likely hides a deep, global ocean. Galileo’s Europa image data has been remastered here, with improved calibrations to produce a color image approximating what the human eye might see. Europa’s long curving fractures hint at the subsurface liquid water. The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support life, making Europa one…

木卫一的真实色彩

木卫一的真实色彩

2022年12月11日 Io in True Color Image Credit: NASA, JPL, Galileo Project Explanation: The strangest moon in the Solar System is bright yellow. The featured picture, an attempt to show how Io would appear in the “true colors” perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003. Io’s colors derive from sulfur and molten silicate rock. The unusual surface of Io is kept very young by its system of active volcanoes. The intense tidal gravity of Jupiter stretches Io and damps wobbles caused by Jupiter’s other Galilean moons. The resulting friction greatly heats Io’s interior, causing molten rock to explode through the surface. Io’s volcanoes are so active that they are effectively turning…

斜塔与活跃红日

斜塔与活跃红日

2022年4月1日 Leaning Tower, Active Sun Image Credit & Copyright: Antonio Tartarini Explanation: The natural filter of a hazy atmosphere offered this recognizable architecture and sunset view on March 27. Dark against the solar disk, large sunspots in solar active regions 2975 and 2976 are wedged between the Duomo of Pisa and its famous Leaning Tower. Only one day later, Sun-staring spacecraft watched active region 2975 unleash a frenzy of solar flares along with two coronal mass ejections. The largest impacted the magnetosphere on March 31 triggering a geomagnetic storm and aurorae in high-latitude night skies. On March 30, active region 2975 erupted again with a powerful X-class solar flare that caused a temporary radio blackout on planet Earth. Tomorrow’s picture: a colour out of space…

木卫二

木卫二

2022年1月15日 Galileo’s Europa Image Credit: NASA, JPL-Caltech, SETI Institute, Cynthia Phillips, Marty Valenti Explanation: Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon’s icy surface likely hides a deep, global ocean. Galileo’s Europa image data has been remastered here, with improved calibrations to produce a color image approximating what the human eye might see. Europa’s long curving fractures hint at the subsurface liquid water. The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support life, making Europa one…

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…

银河

银河

2021年07月03日 Along the Milky Way Image Credit & Copyright: Rolf Weisenfeld Explanation: You can’t walk along the Milky Way. Still, under a dark sky you can explore it. To the eye the pale luminous trail of light arcing through the sky on a dark, moonless night does appear to be a path through the heavens. The glowing celestial band is the faint, collective light of distant stars cut by swaths of obscuring interstellar dust clouds. It lies along the plane of our home galaxy, so named because it looks like a milky way. Since Galileo’s time, the Milky Way has been revealed to telescopic skygazers to be filled with congeries of innumerable stars and cosmic wonders. Tomorrow’s picture: Facing Mars 银河 影像提供与版权: Rolf Weisenfeld 说明:…

木卫二的重制影像

木卫二的重制影像

2019 November 29 Galileo’s Europa Remastered Image Credit: NASA, JPL-Caltech, SETI Institute, Cynthia Phillips, Marty Valenti Explanation: Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon’s icy surface likely hides a deep, global ocean. Galileo’s Europa image data has been remastered here, using improved new calibrations to produce a color image approximating what the human eye might see. Europa’s long curving fractures hint at the subsurface liquid water. The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support…