NASA says a sonic boom from Artemis2 could happen, but it's not a guarantee, as the Orion Spacecraft gets closer to splashdown off the coast of San Diego Friday afternoon.
Officials say there's a lot of science behind the boom. It happens when shock waves from an aircraft outruns its own sound wave at 760 miles per hour.
That causes the waves to compress and then a boom. If it happens, NASA says it will be heard and felt in a radius of at least 30 miles.
Residents can experience a loud bang, windows rattling and an occasional picture askew. The boom will happen anytime from 4:53 p.m. and 5 pm. Pacific Time.
KOGO will cover the splashdown live Friday afternoon.