On July 26, NASA’s Solar Dynamics Observatory (SDO) noticed something peculiar about its normally uninterrupted view of the sun — a chunk was missing. But never fear, a black hole didn’t just show up swallowing some of our nearest star’s superhot plasma, it was just the moon photobombing the sun’s portrait.
The SDO has been continuously watching the sun since 2009. The high-definition space observatory orbits the Earth in a very special way that our planet rarely slips into shot (though, occasionally, even that happens during “eclipse season”). The moon, however, is a more regular visitor in the SDO’s observations. Approximately twice a year, the moon’s orbit around the Earth causes it to drift in front of the sun creating a lunar transit.
As can be seen from this transit, the edge of the moon is very sharp and defined as our planet’s only natural satellite has no atmosphere. Compare this to when the Earth blocks the solar view and you can see the hazy upper atmosphere allowing some of the brightest active regions penetrate.