Pluie coronale sur le Soleil
Does it rain on the
Sun?
Yes, although what falls is not water but extremely hot
plasma.
An example occurred
in mid-July 2012 after an eruption on the Sun that produced both a
Coronal Mass Ejection
and a moderate solar flare.
What was more unusual, however, was what happened next.
Plasma in the nearby
solar corona
was imaged cooling and falling back, a phenomenon known as
coronal rain.
Because they are electrically charged,
electrons,
protons, and
ions in the rain were
gracefully channeled along existing
magnetic loops near the Sun's surface,
making the scene appear as a surreal three-dimensional sourceless waterfall.
The resulting
surprisingly-serene spectacle is shown in
ultraviolet light
and highlights matter glowing at a temperature of about 50,000
Kelvin.
Each second in the
featured time lapse video
takes about 6 minutes in real time, so that the entire
coronal rain sequence lasted about 10 hours.
Recent observations have confirmed that that coronal rain can also occur in smaller loops for as long as 30 hours.