A roughly five-ton piece of a SpaceX Falcon 9 rocket, known as ET, is expected to collide with the moon at approximately 5,400 miles per hour near the crater Einstein on the western lunar limb. Bill Gray, who runs Project Pluto and develops astronomical tracking software, first calculated the impending impact and has been monitoring the object since.

Benjamin Fernando, a postdoctoral researcher at Los Alamos National Laboratory in New Mexico and lead author of a recent study on the event, told ABC News, "We expect that to vaporize the booster, create a flash of light, probably a plume of ejecta -- dust, regolith, other stuff mixed into it -- and of course excavate a fresh crater on the lunar surface."

Fernando emphasized that the impact presents a unique scientific opportunity. Unlike natural meteoroid strikes, whose mass and speed are often unknown, the known parameters of this rocket stage allow researchers to use the event as a "calibration event to test all of the techniques that we use for studying natural impacts."

With NASA planning to return astronauts to the moon as early as 2028 and eventually establish a permanent lunar base, Fernando noted that this impact also provides a chance to study the risks lunar impacts pose to people and equipment. He added, "These sorts of things are going to happen more and more often. And as we have more astronauts on the lunar surface, more lunar infrastructure habitats, for example, we need to understand how much of a risk these impact events actually pose."

The upper stage was abandoned in a moon-crossing high-Earth orbit after its mission delivering two lunar landers. This event follows the crash of the lander Resilience, which lost communication 90 seconds before landing on the lunar surface.

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