Was it a sonic boom? Axiom 3 crew splashes down off Florida coast

After spending an extra six days in space because of stormy weather near Florida, the first all-European private astronaut mission returned home to Earth early Friday morning.

The crew finally separated from the International Space Station on Wednesday morning, beginning their two-day journey back to Earth. It came splashing down off the Florida coast around 8:30 a.m. EST. 

FOX 35 News received several phone calls and emails reporting a "sonic boom" or "explosion" after the splashdown caused a large noise. Some said it even shook their homes. 

A sonic boom is defined as "a sound resembling an explosion produced when a shock wave formed at the nose of an aircraft traveling at supersonic speed reaches the ground," according to the Merriam-Webster dictionary. 

The Federal Aviation Adminstration (FAA) told FOX 35 in a statement, "only military aircraft create sonic booms."

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The crew was originally scheduled to come home Saturday, but SpaceX announced that the crew of four would spend additional days in space due to poor weather conditions this week in the recovery zone off Florida

SpaceX can retrieve the Crew Dragon spacecraft and its crew from seven potential landing sites off both Florida's Gulf and Atlantic coasts. However, wave height, wind and rain must meet NASA's recovery criteria for the safe return and retrieval of the Dragon spacecraft.

After days of weather delays, the storm system causing problems for the Ax-3 return moved up the East Coast, clearing the way for the crew's departure. 

After 20 days in space, the Dragon pushed itself away from the station on Wednesday at 9:20 a.m. ET as it was over the South Pacific Ocean

"We hope you had a wonderful time on station, and we’re looking forward to seeing your smiling faces," SpaceX ground control told the crew.

The Ax-3 crew spent two more days in low gravity as Dragon orbited the Earth, setting up for the splashdown off the coast of Daytona Beach, Florida about 47.5 hours later. The time between departure from the ISS and when the Dragon arrives on Earth depends on where the station is in relation to the landing zone and weather conditions.  

The spacecraft re-entered Earth's atmosphere at 17,500 mph, using a parachute system to slow down to a few mph before landing. Dragon then softly plopped down in the ocean off Florida's coast where NASA and SpaceX recovery teams were waiting. 

While in orbit, the crew conducted more than 30 experiments in microgravity. The Ax-3 experiment topics included biomedical research, sleep, bone health, space weather and cooking pasta in space. With their extra days in space, the private astronauts conducted more research and spent time doing outreach events with their home countries. 

The mission marked the first all-European human spaceflight to the ISS with a crew from Italy, Turkey and Sweden. The spaceflight marked the second Axiom Space mission for López-Alegría who is the company's chief astronaut and a former NASA astronaut. He was also the commander on Axiom Space's inaugural mission to the ISS in April 2022.