Cape Canaveral, Florida - On Friday, four astronauts took off with a SpaceX rocket to the International Space Station. They were reminded of the potential dangers of space travel on their flight when they almost collided with an unknown flying object!

Last Friday morning, four astronauts on board one of SpaceX's Dragon Capsules took off from the Cape Canaveral spaceport in Florida in the direction of the International Space Station (ISS).

The launch was successful, but at 1:43 PM ET, after the astronauts had already been orbiting the earth for about seven hours and were just getting ready to go to sleep, they got an urgent call from Mission Control.

A calm, steady voice instructed them to put on their space suits, get into their seats, and brace for a potential collision with an unknown object. They had no idea how big, only a brief window of time for when the object could potentially hit the capsule.

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NASA spokesperson Kelly Humphries told the science website Futurism, "The NASA/SpaceX team was informed of the possible conjunction by US Space Command," a conjunction being the scientific term for a collision. "The object being tracked is classified as 'unknown'."

US Space Command spokesperson Erin Dick also informed Futurism that NASA had received their notification about the potential collision just minutes before from the Pentagon.

However, there was no time to initiate an evasive maneuver, as reported via Twitter by reporter Jamie Groh, who followed the capsule's flight live.

As Space.com reported, it ended up being a sit and wait situation. The astronauts needed to be in their suits should the collision break the capsule open.

Even if the unidentified object was relatively tiny, space junk reaches speeds of 18,000 miles per hour in orbit, which is seven times faster than a bullet.

This would make even a fleck of paint or shard of metal capable of causing significant damage to the Dragon Capsule.

"After further analysis, the 18th Space Control Squadron quickly determined there was no conjunction threat, all aboard are safe and the spacecraft was not at risk," Erin Dick said.

According to Kelly Humphries, NASA found out afterwards that there had always been a distance of at least 45 kilometers between the Dragon Capsule and the UFO.

This may sound like a relatively long distance, but at the fast speeds of objects in orbit, it's no more than a stone's throw in space, and the flight could have ended badly.

It's still a mystery what the unknown flying object was that almost got in the way of the SpaceX crew.