NASA's SDO (Solar Dynamics Observatory) has been observing
the sun for three years. Now, with this video, you can
view all of it in just three minutes. It is a really beautiful video.
Some explanatory text for the video is as follows:
SDO's Atmospheric Imaging Assembly (AIA) captures a shot of the sun every
12 seconds in 10 different wavelengths, but the images shown here are
based on a wavelength of 171 Angstroms, which is in the extreme ultraviolet
range. It shows solar material at around 600,000 Kelvin. In this wavelength
it is easy to see the Sun's 25-day rotation as well as how solar activity
has increased over three years as the Sun's solar cycle has ramped up
towards the peak of activity in its 11-year cycle.
You'll also notice that during the course of the video, the Sun subtly
increases and decreases in apparent size. This is because the distance
between the SDO spacecraft and the Sun varies over time. The image is,
however, remarkably consistent and stable despite the fact that SDO orbits
the Earth at 6,876 miles per hour and the Earth orbits the sun at
67,062 miles per hour.