Observing Comets
and the
Association of Lunar and Planetary Observers


Comets come from the deepest reaches of outer space. Some of them visit Earth’s neighborhood only once in a lifetime, or even only once in a thousand years or more. Hunting them makes the proverbial needle in a haystack seem easier to find than the nose on your own face. Yet, Carl Hergenrother has discovered four comets and a more than a dozen asteroids. Some of the more interesting comets discovered in recent years are presented in this lecture as well as the science contributed by observers with modest backyard equipment. The mission and structure of the Association of Lunar and Planetary Observers (ALPO) is also explained.

Carl Hergenrother is the Coordinator of the Comets Section of ALPO, and has just begun a term as Executive Director. 2022 will mark ALPO’s 75th anniversary devoted to the study of all bodies in our solar system and of planets in alien systems. Their primary goals are to stimulate, coordinate, and promote the study of these bodies using methods and instruments that are available to both amateur and professional astronomers. The ALPO Comets Section has been at the forefront of citizen science comet research since the late 1950s.

Carl spent most of the past decade working on NASA’s OSIRIS-REx mission to retrieve samples from near-Earth asteroid Bennu. His two primary contributions to OSIRIS-REx were the selection of Bennu as the target and the novel and surprising discovery that Bennu is routinely ejecting small particles of itself into space. He has since moved on to Ascending Node Technologies, LLC, a small business developing spacecraft planning and operations software..


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