FARMINGTON — On a Friday evening in October, the San Juan College Planetarium will dim its lights and turn the night sky into a kind of literary scavenger hunt. The show is called "The Astronomy of Harry Potter," and its premise is simple: many of the names J.K. Rowling gave her wizards and witches were borrowed from the real heavens, and most readers never noticed.
The presentation, part of the planetarium's monthly AstroFriday series, will be held at 6:30 p.m. and again at 7:30 p.m. in the planetarium on the San Juan College campus. Admission is free. After the second show, weather permitting, the planetarium will host a free public stargaze at 8:30 p.m. in the courtyard behind the building, near the Connie Gotsch Theatre.
The show was developed by David Mayeux, the planetarium's director and an astronomy instructor at the college. Mayeux said the idea came to him when he realized how many astronomical objects share names with characters in the series.
"Did you know that the character of Sirius Black, Harry's godfather in the series, was named for the brightest star in the night sky as seen from Earth?" Mayeux said. "And that it is also the chief star in the constellation of the Great Dog, and he isn't the only character with an astronomical name."
That pairing is no accident. Sirius is the Dog Star, the brightest point of light in the constellation Canis Major — the Great Dog — and in the books Sirius Black is an Animagus who transforms into a large black dog. The Black family, in particular, was written as a dynasty that named its children after the stars, a detail the planetarium show will unpack.
Mayeux's presentation is fully live — not a recorded film — and he will do more than point at a screen. He will show the audience how to find the same objects in the actual sky with their own eyes, a skill that carries over to the stargaze an hour later.
The stargaze is the second half of the evening and the part with no capacity limit. The planetarium itself seats only 60 people, and seating is first-come, first-served, with no late admittance once a show begins — a rule meant to preserve viewers' dark adaptation. The courtyard gathering, by contrast, is open to anyone who shows up, and telescopes will be set up for up to an hour.
Mayeux said the waxing gibbous Moon and Saturn should be visible that night. The telescope targets include several binary stars: Albireo, a celebrated gold-and-blue pair; 61 Cygni, a double star of two orange suns that is also known as Bessel's Star; and Polaris, the north star, which is itself a binary system. If conditions are especially favorable, Mayeux said, the group may also catch the globular cluster M13 in Hercules, the Ring Nebula (M57) in Lyra, the Wild Duck Cluster (M11) in Aquila, the Dumbbell Nebula (M27) in Cygnus, and possibly even M31, the Andromeda Galaxy.
The name "Bessel's Star" is a nod to the German astronomer Friedrich Bessel, who in 1838 used 61 Cygni to make the first successful measurement of a star's distance from Earth, calculating its parallax and arriving at a figure close to the modern value of about 11.4 light-years. The star is nicknamed the "Flying Star" for its unusually rapid apparent motion across the sky. Albireo, meanwhile, is a favorite of amateur astronomers because its two components — a brighter golden star and a fainter blue companion — show a striking color contrast in a small telescope.
The planetarium itself is a modest facility that punches above its size. It houses a 24-foot dome with a seating capacity of 60 and a digital star projector, and it charges no admission for any of its presentations. It runs school shows on Tuesdays, Wednesdays and Thursdays from September through May, monthly daytime solar viewing sessions on Friday mornings, and public shows once a month on Friday evenings. The AstroFriday series is described by the city's tourism office as "a huge hit with local stargazers."
The courtyard where the stargaze will be held sits outside the Connie Gotsch Theatre, a venue with its own local history. Formerly known as the Little Theatre, it was renamed and renovated in 2021 in honor of Connie Gotsch, who worked at the college's radio station, KSJE 90.9 FM, from 1990 until 2012 and hosted a long-running arts program called "Roving with the Arts." After her death in 2012, her estate established the Connie Gotsch Arts Foundation, which helped fund the theater's renovation. The art-deco lobby now includes a display case honoring her work.
Mayeux is a familiar figure in the Four Corners astronomy community. When an annular "ring of fire" solar eclipse passed directly over Farmington in October 2023, he hosted a public viewing event in the same courtyard, setting up one telescope with a solar filter and a digital eyepiece to share the image on screen, and another projecting the eclipse onto a light-colored surface so several people could watch at once. He has also spoken publicly about the Artemis program.
For the Harry Potter show, sky maps will be available while supplies last. The planetarium notes that it reserves the right to substitute shows, and that a date change is possible, though unlikely.
The event's appeal may lie in that collision of worlds — a children's book series and the actual physics of the night sky. Rowling's wizarding families drew their names from the same stars that will be overhead in Farmington that night, and for one hour the planetarium will treat the two as what they always were: the same map, read two different ways.
For more information, visit the planetarium's website at sanjuancollege.edu/planetarium or call David Mayeux at (505) 566-3361.