Butch Wilmore and Suni Williams, two veteran NASA astronauts, have been stuck in space for seven weeks longer than initially expected.

Dr Sarah Webb, astrophysicist at Swinburne University of Technology, spoke to 6PR Afternoons host Julie-anne Sprague on the reasons behind the delay.

“They are making sure these astronauts are going to return safely and taking their time to do so,” she said.

Click PLAY to hear the full conversation.