A spent SpaceX rocket stage that has been drifting through space since launching two lunar landers more than a year ago is expected to crash into the moon on Wednesday, which will create a new impact crater and a cloud of dust and debris.

According to space tracking expert Bill Gray, the rocket stage is projected to strike the lunar surface at roughly 5,400 mph (8,700 kph), or about seven times the speed of sound, Reuters reported.

The impact is expected to occur near Einstein Crater along the moon’s sunlit western edge.

Astronomers and skywatchers are hoping to witness the collision and the plume of material that will be blasted into space. 

Since the impact is expected to take place during the early morning hours, observers in the eastern United States, eastern Canada and much of South America are expected to have the best opportunity to see the event, weather permitting.

The collision was not planned and involves the rocket’s upper stage, which remained in space after completing its mission to send a pair of lunar landers toward the moon.