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Ultraviolet Light

Electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays. Ultraviolet observations are crucial for studying hot astronomical objects like accretion disks around black holes.

Source: science.nasa.gov

APODs including "Ultraviolet Light"

A Solar Ballet

15/01/2013

Video Credit: NASA Astronomy Picture of the Day

Sometimes, the Sun itself seems to dance. On just this past New Year's Eve, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence erupting from the Sun's surface. The dramatic explosion was captured in ultraviolet light in the above time lapse video covering four hours. Of particular interest is the tangled magnetic field that directs a type of solar ballet for the hot plasma as it falls back to the Sun. The scale of the disintegrating prominence is huge -- the entire Earth would easily fit under the flowing curtain 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. As the Sun nears Solar Maximum this year, solar activity like eruptive prominences should be common.