Airbus Defence and Space

Airbus Defence and Space assembles most precise "clock ensemble" ever for operation in space

ACES to test Einstein’s general theory of relativity

It may not look like a clock, but that’s exactly what it is. By assembling the ACES (AtomicClock Ensemble in Space), Airbus Defence and Space is creating a “super clock” for the European Space Agency (ESA) that comprises two atomic clocks as well as laser and microwave links to the Earth. ACES will run at a precision equal to 1x10-16 a loss of just one second every 300 million years.
ACES is tasked with testing Einstein’s general theory of relativity. As time is linked to gravity, it does this, put simply, by comparing the time recorded by the two space clocks with atomic clocks on Earth; even under different gravity conditions. The ACES experiment payload will also help improve the precision and long-term stability of international atomic time (TAI) and coordinated universal time (UTC). ACES is scheduled to be launched into space in 2017 and will be attached to the exterior of the International Space Station’s European Columbus module.

About Airbus Defence and Space

Airbus Defence and Space is a division of Airbus Group formed by combining the business activities of Cassidian, Astrium and Airbus Military. The new division is Europe’s number one defence and space enterprise, the second largest space business worldwide and among the top ten global defence enterprises. It employs some 40,000 employees generating revenues of approximately €14 billion per year.

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ACES (Atomic Clock Ensemble in Space)ESAAirbus Defence and Space