Abstract
Mars has a well-formed ionosphere that is formed mainly by photoionization and photochemistry of its neutral atmosphere, and some relatively minor processes such as electron impact ionization and day-to-night transport. MAVEN has been studying the Martian system since its orbit insertion in 2014, and has returned the most complete dataset for aeronomy science at the red planet.
While sampling the dayside ionosphere, MAVEN has found several instances when the ionospheric densities drop significantly before being restored back, hinting at localized structures that are formed by thus far poorly understood physical mechanisms. In this contribution, we study specific test cases in detail, using a combination of in-situ particles and fields data from the MAVEN spacecraft to provide a context of the environment surrounding these structures and help understand the possible physical mechanisms behind them.