In a rare cosmic occurrence, Mercury is moving across the sun.
It’s called the transit of Mercury, and it started at around 7 a.m. local time in Washington.
During the event, the smallest planet will move across the sun for about 7.5 hours.
The last transit was in 2006, and the next one will be in 2019 and then again in 2032. Transits happen around 13 times each century, according to astronomers.
The transit are rare because Mercury’s orbit is tilted relative to Earth. Mercury orbits the Sun once every 88 days.
Mercury is one third the size of Earth.
Sky watchers in eastern North America, Western Europe, Northwestern Africa and South America should have the best views of the event. To see it, you’ll want to make sure your binoculars and telescopes have filters to protect your eyes from the sun’s brightness.
NASA is also live streaming the event.
Here's a video about the event: