Leland Melvin claims he came across the object - which NASA said was a piece of ice - while he was working on the Space Shuttle Atlantis
A NASA astronaut has claimed he once saw an "alien-like, organic object" floating outside his space shuttle.
Leland Melvin, 54, worked as an engineer on board Atlantis when he spotted the "translucent" item while orbiting Earth.
The US astronaut said he saw an 'alien-like, organic' object while he was in space
He admits that NASA said the incident was just ice breaking away from the vessel.
In a chat on Twitter with fans about his experiences in space he was asked if he had ever seen any aliens or UFOs.
Melvin revealed that he had seen "something, organic, alien-like" in the payload bay of the shuttle when he was working with colleague Randy Bresnik.
The astronaut said the object he saw was "translucent, curved, organic looking" – ending his tweet with an alien emoji.