My local astronomical society ran a survey to find out what subjects members might want covered. One member requested something about chemistry and I decided to prepare an introduction to astrochemistry as a series of short talks looking at one element at a time, its basic chemistry and aspects of interest to astronomers.
The series began in 2016 with the first short talk on hydrogen, and this was followed by a second short talk on the heavy hydrogen isotopes deuterium and tritium. The final short talk in 2016 was about helium and the noble gases.
The series will continue well into 2017 (possibly beyond) with the next short talk provisionally about lithium and the alkali metals. This will be followed by talks on beryllium, boron, carbon, nitrogen, oxygen, fluorine and their corresponding groups, with subsequent talks on selected transition metals, lanthanides and actinides.
I also regularly present talks for astronomical societies on chemical, biological and historical aspects of astronomy and astronautics.