NASA - National Aeronautics and Space Administration

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.

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

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

Karen C. Fox
NASA's Goddard Space Flight Center