Here's one sight I'd sure like to see! A comet the size of a mountain traveling at 126,000 miles per hour.
It passed 86,000 miles from the surface of mars, which by space standards, is pretty close.
In fact, it's so close, NASA had to hide its orbiters and rovers that are exploring mars behind the planet, to protect them from dust kicked up by the comet.
The machines are fine, and even managed to capture some pretty incredible photos of the comet as it passed by. Scientists will use the photos to learn more about comets like this one.