If you've ever taken a look at the Moon (even with your naked eye, but especially through a telescope or satellite photos), then you know that its surface is covered in marks.
Craters dot the Moon like freckles, or chocolate chips on a cookie. Many of them are thousands, millions, even billions of years old.
But at least one was made only one month ago!
Astronomer Daichi Fujii, who works at the Hiratsuka City Museum in Japan, used his own home equipment to capture video of a meteor striking the surface of the Moon. This impact is known as a lunar flash. You can see it in the video below as a brief burst in the lower right of the frame.
— 藤井大地 (@dfuji1) February 24, 2023
Different world, different rules
Meteors are out there all the time, and the Earth actually encounters them often. The reason we don't really have to deal with them that much? They are small enough that our atmosphere takes care of them. They burn up in a brilliant fireball long before they ever reach the surface.
But the Moon is different. It has zero atmosphere, so there's nothing for a meteor to pass through as it approaches. It flies toward the Moon at rapid speeds (try about 60 km, or 40 miles, per second, meaning they travel the same distance in a second that a city car does in an hour). And when it hits, the impact of even a basketball-sized meteor is tremendous. Here is how Fujii explained it himself in his tweet:
"This is a picture of the lunar impact flash that appeared at 20:14:30.8 on February 23, 2023, taken from my home in Hiratsuka (replayed at actual speed). It was a huge flash that continued to shine for more than 1 second. Since the moon has no atmosphere, meteors and fireballs cannot be seen, and the moment a crater is formed, it glows."
And we're glowing just looking at it. So amazing!