NASA’s Solar Dynamics Observatory, more commonly known as SDO, has spent the last three years taking pictures of the sun, showing off its steady increase in activity as its latest 11-year cycle nears its peak. As part of the project, NASA has taken some of the images and compiled them into a single 3-minute video, which makes it easy to see the gradual increase in solar activity.
SDO’s Atmospheric Imaging Assembly (AIA) captures a shot of the sun every 12 seconds in 10 different wavelengths. The images shown here are based on a wavelength of 171 Angstroms, which is in the extreme ultraviolet range and 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.
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.
More information about this video, as well as full HD version of all four wavelengths and print-resolution stills are public domain and can be viewed and downloaded at: http://svs.gsfc.nasa.gov/vis/a010000/a011200/a011255/