Abstract The Venusian O( 1 S– 1 D) 5577 Å “oxygen green line” has been an enigmatic feature of the Venusian atmosphere since its first attempted observation by the Venera spacecraft. Its first detection in 1999 and subsequent detections point to a unique auroral phenomena. However, the lack of ( 1 D– 3 P) 6300 Å “oxygen red line” emission suggests that the green line originates from deep in the ionosphere, much lower than current models predict. Here, we present 16 years of ground‐based observations of the Venusia…

Abstract Launched in 2003, the European Space Agency’s Mars Express (MEX) has been orbiting Mars for 20 years and its instruments have performed continuous monitoring of the conditions in the Martian atmosphere, providing one of the most complete datasets of atmospheric parameters ever collected for Mars. This article provides an overview of the observations of the vertical structure of the Martian atmosphere performed by MEx, which led to the identification of peculiar phenomena that affect the atmospheric circul…

Venus exhibits strong and changing contrasts at ultraviolet wavelengths apparently related to the clouds and the dynamics in the cloud layer, but to date their origin continues to be unknown. We investigate the nature of the UV contrasts exhibited by Venus clouds by examining possible correlations between the thermal structure inferred from radio occultation data and UV brightness from imagery data, both observed with Venus Express. We analyse Venus Express images obtained from 11 hours before to a few hours after…

Radio occultation measurements at Venus have provided invaluable insights into the planet's atmospheric properties. One particularly intriguing phenomenon observed during these measurements is radio scintillations, characterized by rapid fluctuations in signal intensity. Radio scintillations are caused by small-scale irregularities in the refractive index associated with small-scale variations of the atmospheric density. A possible source of these density variations is vertical propagating internal gravity waves, …

The Martian magnetosphere is unique in our Solar system because it contains components of an induced and an intrinsic magnetosphere. Since we can not get a global snapshot of the magnetosphere at a given time we use a statistical picture based on a large number of plasma measurements. Depending on the choice of coordinate system used and the selection of the data we can observe different features of the Martian magnetosphere. If, for example, we map data in the Martian Solar Electric (MSE) coordinate system with a…