ESA’s Atomic Clock Ensemble in Space (ACES) has arrived at NASA’s Kennedy Space Center in Florida, United States. This cutting-edge European experiment will test fundamental physics from the outside of ESA’s Columbus module on the International Space Station, measuring time from orbit with unprecedented precision.

Earlier this month, ACES departed from Europe for its transatlantic flight. Since its arrival at the Kennedy Space Center, ACES completed critical preparations in the Space Station Processing Facility cleanroom.

Teams from ESA, Airbus and NASA carefully unboxed and unwrapped the payload to check all was well with the precious instrument. After engineers successfully performed these system checks, they wrapped and boxed ACES once more, placing it in a special magnetic “G-iron” shield to protect its sensitive atomic clocks.

ACES will be transported to SpaceX for final integration with the Falcon 9 vehicle ahead of its scheduled launch in less than a month, on 21 April.