Watch a ‘Gorilla’ on the Loose in the International Space Station

American astronaut Scott Kelly, who has a knack for keeping things interesting aboard the International Space Station, recently dressed up in a giant gorilla suit and chased after his fellow astronauts.

In a video posted by his brother on Twitter on Monday, Kelly is shown wearing the gorilla suit and chasing down another astronaut, who quickly flees from the unexpected passenger.

Multiple media outlets reported that the suit was sent to Kelly by his twin brother, retired astronaut Mark Kelly.

Scott Kelly is nearing the end of his year in space, a mission that aims to help understand the effects of prolonged zero-gravity exposure on the human body. TIME has been following Kelly throughout for a series of videos that can be watched here.