May 2023
The Backyard Astronomer
Adam England

Spring Serpents and Clusters

Spring has sprung in northern Arizona, and with it comes the return of budding flora and emerging fauna. The sky also graces us with clusters in bloom, and the slithering serpents that herald their homecoming.

The constellation Serpens is often depicted as two halves of a snake, as held by Asclepius, the Greek god of medicine, aka Ophiuchus. The snake was observed to shed its skin, an act seen by the ancients as a sort of rebirth and resurrection, and the return of the constellation Serpens brings the rebirth of the plant and animal life that lay dormant through the winter. The serpent begins to rise in the eastern sky during May, bringing with it a host of deep-sky objects for your viewing pleasure.

M5 position projected for May15 this year

Messier 5 (M5) is a globular cluster near the head of the Serpent, where more than 100,000 stars densely pack into a ball of space about 165 light-years in diameter. Despite having so many individual stars, its distance from Earth at around 25,000 light-years makes it appear to the naked eye as a single, faint star. Through your binoculars you’ll be able to see that it’s not a single object, and a larger telescope can resolve many of the brighter individuals, which include 105 variable stars, two millisecond pulsars and a dwarf nova. The entirety of M5 is speeding away from our solar system at more than 50km/s, so by the time you finish reading this article it will have moved a full Earth diameter farther from your backyard telescope.

M5 imaged by the 32-inch Schulman scope on Mt. Lemmon

The most daring backyard astronomers can also hunt galaxies off the head of the Serpent. Hoag’s Object is an extremely rare ring galaxy, and Seyfert’s Sextet is a group of six galaxies that are gravitationally bound like a globular cluster, albeit over a grander scale.

Hoag's Object imaged by Hubble Space Telescope, 2001

For early-bird astronomers Jupiter and the moon will be dancing together on the morning of May 17. Jupiter will be hidden behind the moon as it rises from the eastern horizon, in what is known as a lunar occultation. Jupiter will reemerge at 5:17am, with sunrise just a few minutes later at 5:26, potentially obscuring the view for all but the most astute observers.

If you would like to learn more about the sky, telescopes, or socialize with other amateur astronomers, visit us at prescottastronomyclub.org or Facebook @PrescottAstronomyClub to find the next star party, Star Talk, or event.

Adam England is the owner of Manzanita Financial and moonlights as an amateur astronomer, writer, and interplanetary conquest consultant. Follow his rants and exploits on Twitter @AZSalesman or at Facebook.com/insuredbyadam.