Astronauts take one more spacewalk before SpaceX crew prepares for return to Earth. 

For the fourth time in about a month, astronauts aboard the International Space Station ventured outside their module to conduct a variety of maintenance activities. 

NASA's Bob Behnken and Chris Cassidy floated out of the International Space Station for more than five hours on Tuesday.

Behnken and fellow SpaceX crew member Doug Hurley, who monitored the spacewalk from inside the capsule, will return to Earth early next month. 

They blasted off from Cape Canaveral on May 30. Cassidy and two Russian cosmonauts will remain on the ISS for several more months.