NASA Video: Three Years of the Sun in Three Minutes
Posted on April 22, 2013
NASA's Solar Dynamics Observatory (SDO) has maintained nearly unbroken coverage of the sun over the past three years. This video shows three years of the sun at a pace of two images per day. In the video the sun subtly increases and decreases in apparent size. NASA says this is because the distance between the SDO spacecraft and the sun varies over time. The SDO's Atmospheric Imaging Assembly captures a shot of the sun every 12 seconds in 10 different wavelengths. The images shown in the video are based on a wavelength of 171 angstroms. Take a look:
The image above is a composite of 25 separate images spanning the period of April 16, 2012, to April 15, 2013.