Conjugate observations on board a satellite and on the ground of a remarkable MLR-like event

F. Němec (1, 2) , T. Raita , Michel Parrot (1) , O. Santolik (2) , T. Turunen (3)

1 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
2 IAP - Institute of Atmospheric Physics [Prague]
3 Sodankylä Geophysical Observatory

Electromagnetic waves observed by low-altitude satellites and on the ground have sometimes-when represented as a frequency-time spectrogram-a form of several nearly parallel and almost equidistant clearly defined lines at frequencies between 1 and 8 kHz. These may drift in frequency and they are usually called Magnetospheric Line Radiation (MLR). Although they have been known for a long time, their origin is still unclear. We present an experimental study using both ground-based and satellite data, showing for the first time a detailed analysis of the simultaneous observations of an MLR-like event on the ground and in the conjugate region. We demonstrate that the individual lines forming the event result (at least in this particular case) from elements reflected between the northern and southern hemispheres.

Domaines: Planète et Univers [physics]

F. Němec, T. Raita, Michel Parrot, O. Santolik, T. Turunen. Conjugate observations on board a satellite and on the ground of a remarkable MLR-like event. Geophysical Research Letters, 2009, 36, ⟨10.1029/2009gl040974⟩. ⟨insu-03036134⟩