A document by Charles Lougheed Bennett. Click on the document to view its contents.

Using data from the Van Allen Probe and Swarm-Bravo satellites, evidence for a persistent population of slow magnetosonic waves in the ionosphere is presented. Dispersion relations from two-fluid analyses of waves in warm plasma are used to interpret and explicate these observations. These waves appear to be continuously present and globally distributed. Their amplitudes systematically decrease with increasing altitude. The amplitudes are also correlated with longitude in a manner consistent with the global distribution of lightning strikes. Evidence for narrow resonances in the Swarm data consistent with doppler shifted Schumann resonance frequencies is presented. In addition, nearly dispersionless fast magnetosonic waves are sometimes also seen. A new method for the analysis of these waves suggests they show the existence of “foamy” plasma bubble “roots” at the base of the ionosphere.

We present a new approach for the analysis of high-resolution digital camera photographs taken by photographers who have fortuitously been able to capture rare events such as the glowing sky phenomenon known as STEVE. This method is especially effective with a time lapse series of images of the night sky taken under constant camera settings with a steady pointing. Stars, planets and satellites seen in such images can be used to determine precise and accurate registration of camera pixels to coordinates of angular altitude and azimuth. The location of satellites in the image enables precise and accurate synchronization of the images. We apply these techniques to the series of photographs of STEVE taken on 25 July 2016. We confirm the altitude structure previously found for STEVE. We find it most likely that the green picket fence features often seen during STEVE events are produced by auroral electron precipitation. With the precipitation assumption, we are able to extract novel information about the energy spectrum of the particles responsible for the production of STEVE luminosity in this particular event. Similar analyses of archived digital photographs may constitute a treasure trove of important data for improved understanding of rare and transient events such as STEVE.

A search for ultraviolet (UV) emissions in satellite data during known STEVE (Strong Thermal Emission Velocity Enhancement) events found that simultaneous subauroral UV arcs (SUA) were not always present in the Southern Hemisphere despite coverage of the conjugate STEVE location. Over the years 2005 to 2020 a total of 108 SUA and STEVE cases were found. A theory is presented in which MeV solar protons guided by the interplanetary magnetic field (IMF) produce these arcs along with STEVE as they precipitate into the atmosphere. Numerous aspects of STEVE and SUA are explained by this theory.

Numerous objects in the ionosphere, including both satellites and meteors, having rapidly varying light intensity and color have been observed in photographs taken during an active aurora. It is suggested that theses variations may be attributed to Auroral Bombardment-induced Light Emission and Sputtering produced by auroral particles striking these objects. This phenomenon is found to increase the brightness of some objects by more than a thousand-fold. It is hypothesized that this phenomenon acting on a remnant dust cloud from ablated meteoric material left along the path of its trajectory through the ionosphere could produce the optical emissions known as STEVE (Strong Thermal Emission Velocity Enhancement). The July 25, 2016 STEVE event is very closely aligned in 3-dimensional direction with the location of the radiant for the Southern Delta Aquariid meteor shower. The best alignment in time with the radiant direction coincides with the appearance of rising flashes of light that occurred 5 minutes before STEVE’s initial visibility. These rising flashes of light might also be caused by the hypothetical meteor.