(report 2015)

The funding obtained from ESEP made it possible to carry out a series of tests on the variation of the electrical potential of a nano-satellite when a Langmuir probe is in operation. These tests took place in October 2015 in the ONERA JONAS set-up. It was necessary to mechanically and electronically adapt the emission device for a CubeSat. The team involved was able to perform five days of tests using JONAS.

During these tests, three types of experiments were carried out :

• the test of the OML (Orbital Motion Limited) theory with respect to the length of the Langmuir probes ;
• the operation of the electron emitter in a plasma cage ;
• the operation of Langmuir probes on a CubeSat and the impact of electron emission on the measurement.

For now, only steps 1 and 2 have been successfully completed. Step 3 requires data analysis work that has not yet been done. The main conclusions at this stage are that :

• the tests of the OML theory confirm the role of the length of the probe ;
• the electron emitter emitted for several hours without difficulty and with very good performance (emission of a few tens of μA for a power consumption of less than 8 mW with a variation of less than 5%).

Contact : François Leblanc, Francois.Leblanc @ latmos.ipsl.fr