Scientists say a leak of fluid in the International Space Station may have been caused by a tiny meteor no larger than a grain of sand. 

They continued to say the leak does not pose a threat to any astronauts aboard the station, which is orbiting about 254 miles above the planet and moving at a speed  up to 17,000 miles per hour. At that speed, a grain of sand would have the impact of a small caliber bullet.

An astronaut was able to plug the leak with his finger while his counterparts struggled for a permanent way to stop the liquid from leaking out into space. The leak could also have allowed all of the oxygen astronauts need to live in just 18 days. It created a hole about two millimeters wide. 

Eventually, they used epoxy on a gauze wipe to seal the hole and more air was pumped in to equalize the pressure from the Progress 70 Spacecraft.

A meteor or space debris 1 cm in size could cause critical damage to the space station but debris 10cm or larger could completely destroy the craft.

-Tony Lee