Defying gravity, albeit only for a few seconds... It is possible on Earth, using CNES zero-G plane. Its parabolic trajectories allows microgravity experiments during 22 seconds, 31 times per flight. For cold atoms microwave atom clocks, the benefit is to get longer interrogation times, and therefore get narrower atomic fringes.

Rubiclock has been installed inside the Airbus A-300 operated by Novespace, with support by CNES, to test its functions in space. Tha campaign lasted from 10 to 14 march 2014, based at Mérignac near Bordeaux. The on-site team was composed of
David Holleville, Luigi De Sarlo, Mehdi Langlois (SYRTE), Jean François Schaff (muQuanS), Simon Bernon (LP2N), François-Xavier Esnault, Philippe Guillemot et Jérôme Delporte (CNES), who particpated to the flights. Technical teams from SYRTE have provided precious support.

Data processing is ongoing, but the campaign is already a success. Scientists have observed 1.25 Hz width fringes, i.e. 8 times better than what is observed in the lab. Fringe width in microgravity is thus comparable to what is obtained by atomic fountains on the ground, but with a device that is 20 times more compact.