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# Space
NASA has watched the sun for three years...here's what it has seen
Scientists are using the data in their efforts to predict space weather.
THREE YEARS AGO, NASA started to watch the sun through its Solar Dynamics Observatory (SDO) so its astronauts and scientists could learn more about Earth’s closest star.
The images caught by SDO reveal types of space weather, such as solar flares and coronal mass ejections (CMEs), which impact life on Earth. The events can send radiation and solar material towards us, interfering with satellites in space on the way.
The images of the “violent dance on the sun” help NASA to understand what causes these giant explosions so it can continue in its aim to one day be able to predict space weather.
SDO’s Atmospheric Imaging Assembly captures a shot of the sun every 12 seconds in 10 different wavelengths. It has provided “virtually unbroken coverage” of the sun’s rise toward solar maximum, the peak of solar activity in its regular 11-year cycle.
The following video shows those three years of the sun at a pace of two images per day. You may notice the sun’s apparent size increases and decreases subtly. This is because the distance between the SDO spacecraft and the sun varies over time. According to NASA thought, the image is “remarkably consistent and stable” despite the fact that SDO orbits Earth at 6,876 mph and Earth orbits the sun at 67,062 mph.
(YouTube: NASAexplorer)
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 kelvins (about 1.08 million F). 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.
Related: Earth isn’t so special anymore, apparently
More: The sun emitted its biggest flare of 2013 today
See: Here’s what dinner looks like in space
