Four astronauts reestablished contact with Mission Control after an expected 40-minute communications blackout — among the longest in human spaceflight history — as they passed behind the moon.

The Orion spacecraft just came within about 4,067 miles of the moon, marking its closest approach.

Over the next few hours, the spacecraft is going to arc around the moon’s far side — sometimes called the “dark side” because it never faces us on Earth.