loading page

Multi-point measurements of the plasma properties inside an aurora from the SPIDER sounding rocket
  • +1
  • Gabriel Giono,
  • Nickolay Ivchenko,
  • Tima Sergienko,
  • Brändström Urban
Gabriel Giono
Royal Institute of Technology

Corresponding Author:ggiono@kth.se

Author Profile
Nickolay Ivchenko
Royal Institute of Technology (KTH)
Author Profile
Tima Sergienko
Swedish Institute of Space Physics
Author Profile
Brändström Urban
Institute of Space Physics
Author Profile


The Small Payloads for Investigation of Disturbances in Electrojet by Rockets (SPIDER) sounding rocket was launched on February 2nd 2016 (21:09 UT), deploying ten free falling units (FFUs) inside a westward travelling auroral surge. Each FFUs deployed spherical electric field and Langmuir probes on wire-booms, providing in situ multi-point recordings of the electric field and plasma properties. The analytical retrieval of the plasma parameters, namely the electron density, electron temperature and plasma potential, from the Langmuir probe measurements was non-trivial due to sheath effects and detailed explanation are discussed in this article. An empirical assumption on the sheath thickness was required, which was confirmed by simulating the plasma environment around the FFU using the Spacecraft Plasma Interaction Software (SPIS). In addition, the retrieved electron density and temperature are also in agreement with the simultaneous incoherent scatter radar measurements from the EISCAT facility. These two independent confirmations provided a good level of confidence in the plasma parameters obtained from the FFUs, and events observed during the flight are discussed in more details. Hints of drift-wave instabilities and Hall current introduced by increased electron precipitation inside a region of enhanced density were observed by the FFUs.