2025年2月23日
Saturn in Infrared from Cassini
Image Credit: NASA, JPL-Caltech, SSI; Processing: Maksim Kakitsev
Explanation: Saturn looks slightly different in infrared light. Bands of clouds show great structure, including long stretching storms. Also quite striking in infrared is the unusual hexagonal cloud pattern surrounding Saturn‘s North Pole. Each side of the dark hexagon spans roughly the width of our Earth. The hexagon‘s existence was not predicted, and its origin and likely stability remain a topics of research. Saturn’s famous rings circle the planet and cast shadows below the equator. The featured image was taken by the robotic Cassini spacecraft in 2014 in several infrared colors. In 2017 September, the Cassini mission was brought to a dramatic conclusion when the spacecraft was directed to dive into the ringed giant.
Your Sky Surprise: What picture did APOD feature on your birthday? (post 1995)
Tomorrow’s picture: lava sky
卡西尼号影像: 红外光波段的土星
影像提供: NASA, JPL-Caltech, SSI; 影像处理: Maksim Kakitsev
说明: 在红外光波段，土星看起来有些许不同。其一，云带上头有大型的结构体，包括颀长的风暴系统。在红外光波段格外醒目的，还有环绕土星北极的不寻常六角云，而这个暗沉的六角形系统，边长和地球之直径相当。六角云发现之前，并无其存在的预测，所以它的起源及稳定度目前仍然是研究的课题。影像中，环拱着土星的著名行星环，投射出土星赤道下方的暗影。这张主题影像，是在2014年由卡西尼号探测器摄于数个红外光波段。在2017年9月，卡西尼号接获指令跃入土星，为卡西尼任务划下戏剧性的句点。
你的天空惊喜: 你生日那天APOD展示了什么照片？（1995年后）
明日的图片: lava sky
