For our advanced class in March 2022, we took advantage of a very good presentation given by RATPAC. The presentation was Ham Radio Science Citizen Investigation, Measuring the Ionosphere with Amateur Radio.
In the presentation, given by Dr. Nathaniel A. Frissell (W2NAF), who is a Space Physicist at the University of Scranton. Dr. Frissell discussed how space weather (by which we mean mostly solar output, flares, sunspots, etc.) affect the ionosphere layers and, by extension, HF communications. He first showed how existing ham radio resources, the Reverse Beacon Network, WSPRnet, and PSKreporter have been collecting information about propagation of radio waves and the condition of the ionosphere. He then discussed several projects that are in progress to allow ham radio operators to build/implement and operate their own personal space weather observatories, and how to contribute that information to scientific research.
This was a bit more advanced than many of the topics we have covered, but provided great insight into how the ionosphere works, how HF radio propagation works, and how space weather impacts our communications on the HF bands (and others).
While we did not record the class ourselves, this presentation, and all of the other RATPAC presentations, are available online for your viewing pleasure. See the links above for more information.