Still from video showing SDO's view of the sun being partially blocked by Earth. Credit: NASA/SDO

(Phys.org)—Twice a year, for three weeks near the equinox, NASA's Solar Dynamics Observatory (SDO) moves into its eclipse season—a time when Earth blocks its view of the sun for a period of time each day.

Any spacecraft observing the sun from an orbit around Earth has to contend with such eclipses, but SDO's orbit is designed to minimize them as much as possible.


Video: NASA's Solar Dynamics Observatory (SDO) has moved into its second season of 2012. This movie from SDO shows Earth moving across the sun from 2:25 to 3:25 a.m. EDT on Sept. 6, 2012. Credit: NASA/SDO/S. Hill

The boundaries of the shadow of Earth on the sun are not perfectly sharp since can see some light from the sun coming through Earth's atmosphere.

Provided by NASA