太阳之舞

Sun Dance
Video Credit: NASA, SDO; Processing: Alan Watson via Helioviewer

Explanation: Sometimes, the surface of our Sun seems to dance. In the middle of 2012, for example, NASA’s Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence that seemed to perform a running dive roll like an acrobatic dancer. The dramatic explosion was captured in ultraviolet light in the featured time-lapse video covering about three hours. A looping magnetic field directed the flow of hot plasma on the Sun. The scale of the dancing prominence is huge — the entire Earth would easily fit under the flowing arch of hot gas. A quiescent prominence typically lasts about a month and may erupt in a Coronal Mass Ejection (CME), expelling hot gas into the Solar System. The energy mechanism that creates a solar prominence is still a topic of research. Like in 2012, this year the Sun’s surface is again quite active and features many filaments and prominences.

Tomorrow’s picture: milky way mound

太阳之舞
影片提供: NASA, SDO; 影片处理: Alan Watson via Helioviewer

说明: 有时候，我们太阳表面像是在婆娑起舞。举例来说，在2012年中，美国国家航空航天局绕行太阳的太阳动力学天文台，拍到一个看似在进行类似杂技表演者的鱼跃前滚翻之壮观日珥。而这部延时主题影片，在紫外光波段记录了这个戏剧性事件于大约3小时期间的变化。如影片所示，太阳表面的环状磁场会导引炽热电浆/等离子体的流动。这个跳动日珥的尺度极为庞大，整个地球可轻易塞到拱状炽热流动气体的下方。一个宁静的日珥，通常可持续约1个月，然后或许会爆发日冕物质抛射（CME），把炽热的气体喷入太阳系。然而，生成日珥的能量机制为何，目前仍是研究的课题。不过类似在2012年，今年太阳的表面也是非常的活跃，出现了大量的暗条和日珥。