A photographic instrument on a space telescope constantly taking photographs of the sun -- to make sure scientists don't miss any changes there -- has snapped its millionth photo, its controllers say.
The Atmospheric Imaging Assembly on NASA's Solar Dynamics Observatory uses four telescopes to take an incredible 57,000 photos of the sun each day.
The instrument racked up its millionth shot at 12:49 p.m. ET on Jan. 19 after 5 years of keeping its eyes -- or lenses -- on the sun.
Every 21 seconds the AIA instrument used its four telescopes working together to take 8 images of the sun at 10 different wavelengths.
The huge number of images gathered in rapid succession and at high definition allows solar physicists to better observe and understand fast-moving and transient events occurring deep within the sun's corona.
The boiling corona surrounding the sun can reach temperatures around 1,000 times hotter than its surface, causing giant eruptions known as solar flares and creating space weather that can slam into Earth's magnetosphere, threatening satellite damage and power outages.
Data from AIA helps physicists understand why the Sun's magnetic fields are always on the move, driving its internal dynamics and the resultant activity that causes solar winds and space weather.
Three instruments on board the SDO -- the AIA, the Extreme Ultraviolet Variability Experiment and the Helioseismic Magnetic Imager -- together beam back an impressive 1.5 terabytes of data to earth each and every day, with the AIA accounting for around half of it.
The Solar Dynamics Observatory was launched on February 11, 2010, from Cape Canaveral Air Force Station in Florida, and was designed for a 10-year mission to study the influence the Sun and its activity have on the Earth.
It studies the sun from a geosynchronous orbit 22,238 miles above the Earth.
To honor the occasion of the 100 millionth image, Dean Pesnell, SDO's project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland and Karel Schrijver, the AIA principal investigator at Lockheed Martin in Palo Alto, California, have selected some of their favorite SDO images produced to date.
The image galley can be viewed here.