Launched on February 11, 2010, the mission of NASA’s SDO is to observe the Sun for at least five years in order to understand how our planet’s closest star impacts us on Earth and in the space surrounding the planet.
The Atmospheric Imaging Assembly (AIA) onboard the SDO produced an image every 12 seconds for every day over this three-year period; with each image consisting of ten different wavelengths of radiation.
However, the video only shows two images per day during this same period, with the one wavelength being at 171 Angstroms (which is in the extreme ultraviolet range of the electromagnetic spectrum).
NASA states, “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.”
Besides observing the Sun, the SDO also saw during these three years the following activities:
- a transit of Venus, seen in the video at 01:51:07, on June 5, 2012
- two partial eclipses of the Sun by the Moon; one at 00:30:24, and another one at 02:28:13
- the comet Lovejoy; at 01:28:07, on December 15, 2011
- several large solar flares; one at 01:11:02 on August 9, 2011, the largest flare of this solar cycle, called X6.9 Flare
- two roll maneuvers; one at 00:31:16, and another one at 01:42:29
Check out the YouTube video “SDO - Three Years of SDO Images”, which is also provided above (http://www.youtube.com/watch?v=piuKlpJmjfg).