( CNN ) -- A meteoroid struck the surface of the moon recently , causing an explosion that was visible on Earth without the aid of a telescope , NASA reported Friday . But do n't be alarmed if you did n't see it ; it only lasted about a second . `` It exploded in a flash nearly 10 times as bright as anything we 've ever seen before , '' said Bill Cooke , of NASA 's Meteoroid Environment Office . NASA astronomers have been monitoring the moon for the past eight years , looking for explosions caused by meteoroids hitting the lunar surface . It 's part of a program to find new fields of space debris that could hit Earth . NASA says it sees hundreds of detectable lunar meteoroid impacts a year . Meteor lights up East Coast and social media . None however can match the size of the explosion they say they saw March 17 . NASA says the meteoroid was about 40 kilograms and less than a meter wide , and it hit the moon 's surface at 56,000 mph . It glowed like a 4th magnitude star , NASA says , thanks to an explosion equivalent to 5 tons of TNT . `` It jumped right out at me , it was so bright , '' said Ron Suggs of the Marshall Space Flight Center . Cooke says Earth was pelted by meteoroids at about the same time , but they hit the moon because it has no atmosphere to protect it . Opinion : Meteor shows why it 's crucial to keep an eye on the sky . `` We 'll be keeping an eye out for signs of a repeat performance next year when the Earth-moon system passes through the same region of space , '' Cooke said . If you 're wondering how there can be an explosion on the moon , without oxygen , NASA has the answer for you . It says the flash of light comes not from any type of combustion -- as we typically think of explosions -- but rather by the glowing molten rock at the impact site . Read more space news on CNN Light Years .
The explosion was caused by a meteoroid that hit the lunar surface . It was visible on Earth without a telescope . Comment: The meteoroid was traveling 56,000 mph when it banged into the moon .