2025年4月2日
Jupiter and Ring in Infrared from Webb
Image Credit: NASA, ESA, CSA, STScI; Processing & License: Judy Schmidt
Explanation: Why does Jupiter have rings? Jupiter’s main ring was discovered in 1979 by NASA’s passing Voyager 1 spacecraft, but its origin was then a mystery. Data from NASA’s Galileo spacecraft that orbited Jupiter from 1995 to 2003, however, confirmed the hypothesis that this ring was created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Metis, for example, it will bore into the moon, vaporize, and explode dirt and dust off into a Jovian orbit. The featured image of Jupiter in infrared light by the James Webb Space Telescope shows not only Jupiter and its clouds, but this ring as well. Jupiter’s Great Red Spot (GRS) — in comparatively light color on the right, Jupiter’s large moon Europa — in the center of diffraction spikes on the left, and Europa’s shadow — next to the GRS — are also visible. Several features in the image are not yet well understood, including the seemingly separated cloud layer on Jupiter’s right limb.
Celestial Surprise: What picture did APOD feature on your birthday? (post 1995)
Tomorrow’s picture: open space
韦伯影像: 红外光波段的木星与木星环
影像提供: NASA, ESA, CSA, STScI; 影像处理与授权: Judy Schmidt
说明: 为何木星有环系呢？旅行者1号航天器于1979年路过木星之时，发现了木星的主环，然而它的起源在当时是个谜。后来从1995年到2003年之间绕行木星的伽利略号探测器回传的资料中，方才确认这个环是因为流星体撞击行星环附近的小卫星所产生。例如：当小流星体撞击娇小的木卫十六（Metis）时，会在穿透卫星表面后才汽化爆炸，将土和尘埃扬入绕行木星的轨道里。这幅由韦伯太空望远镜摄于红外光波段的木星主题影像，除了呈现木星及其云层之外，也突显了它的行星环。在影像里，可见右侧以淡斑之姿现身的木星大红斑（GRS）、木星的大卫星木卫二（位于左侧衍射芒的中心）、及大红斑左方的木卫二之影子。影像里还有数个尚未全然了解的特征，其中包括木星右侧邻边上，看似与木星明显分离的云层。
天赐惊喜: APOD在您生日时展示了哪张照片？（1995年后）
明日的图片: open space
