The crews of Discovery and the International Space Station bid one other farewell, closing the hatch between the two spacecraft at 3:42 p.m.

Before exiting the station, the shuttle crew installed a backup drive for the Kibo laboratory’s robotic arm and transferred last minute experiment samples and equipment to Discovery.

The astronauts also enjoyed a few of hours of off-duty time before gathering in the Harmony module at 2:55 p.m. to say goodbye.

The crew begins its sleep period at 7:02 p.m. and awakens at 3:02 a.m. Wednesday.

Undocking from the International Space Station is set for 6:42 a.m.