Atomic Clock Ensemble in Space

Atomic Clock Ensemble in Space is a project lead by the European Space Agency will place an ultra-stable atomic clock on the International Space Station. Operation in the microgravity environment of the ISS will provide a stable and accurate time base for different areas of research, including general relativity and string theory tests, time and frequency metrology, and very long baseline interferometry. The clock is planned to travel to the space station aboard a Space Shuttle, and is to be externally mounted to the ESA's Columbus Laboratory. The clock is planned to operate in orbit for 18-36 months.
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