A Long Snaking Filament on the Sun
Image Credit & Copyright: Alan Friedman (Averted Imagination)
Explanation: Earlier this month, the Sun exhibited one of the longer filaments on record. Visible as the bright curving streak around the image center, the snaking filament’s full extent was estimated to be over half of the Sun’s radius — more than 350,000 kilometers long. A filament is composed of hot gas held aloft by the Sun’s magnetic field, so that viewed from the side it would appear as a raised prominence. A different, smaller prominence is simultaneously visible at the Sun’s edge. The featured image is in false-color and color-inverted to highlight not only the filament but the Sun’s carpet chromosphere. The bright dot on the upper right is actually a dark sunspot about the size of the Earth. Solar filaments typically last from hours to days, eventually collapsing to return hot plasma back to the Sun. Sometimes, though, they explode and expel particles into the Solar System, some of which trigger auroras on Earth. The pictured filament appeared in early September and continued to hold steady for about a week.
Tomorrow’s picture: waving space lizard
影像提供与版权: Alan Friedman (Averted Imagination)
说明: 在这个月初，太阳出现了有记录以来最长的暗条（filament）之一。如上面这幅影像所示，影像中心周围有一道弯曲的亮纹，而这道宛如长蛇的暗条，绵延了将近350,000公里，约莫是太阳半径之半。暗条是被太阳磁场抬升腾空的炽热气体，因此从侧面观看，它是突起于太阳表面的日珥 。在这幅影像里，太阳的临边还可见到另一个较小的日珥。这幅明暗反转的假色主题影像，不仅突显了暗条，也呈现了太阳宛如地毯的色球层。影像右上角的亮斑，其实上是一个大小与地球相近的太阳黑子。太阳暗条通常可存在数小时到数天，最终会坍塌把炽热的电浆释回太阳。不过，有时它们会发生爆发并把粒子射入太阳系里，其中有些甚至会触发地球上的极光。这幅影像里的暗条出现在9月初，并稳定悬浮了约一星期之久。
稳定悬浮: waving space lizard