April is a wonderful time to enjoy the night sky. The winter constellations still hang in the west, offering a chance to enjoy their splendors without braving the January cold. Meanwhile, the spring constellations become ever more prominent in the evening sky each night bringing exciting new sights. April begins with the “realm of the galaxies” high in the SE. With the moon out of the way for the first half of the month, there are dozens of bright clusters, nebulae, and galaxies to be enjoyed with your binoculars, your telescope, or even naked eye.
Not to be missed is the Great Orion Nebula below the belt of Orion. This is our last chance to enjoy it before next winter! Look for it in the western evening sky during the first half of the month. On any April evening, with a good star map, you can find your way to about two dozen of the Messier objects including the Crab Nebula, near the tip of one of Taurus the Bull’s horns. It’s the first object in Charles Messier’s famous catalog.
Some really bright Messier galaxies are well placed: The Whirlpool (M51), The Cigar Galaxy (M82), the Sunflower Galaxy (M63) and the Sombrero Galaxy (M104) are among April’s treasures. The northern sky’s best globular clusters make great targets too: M3, M5, and the Great Globular in Hercules, M13, are all marvelous in a telescope. Easiest to enjoy, perhaps, are the numerous open clusters in the April sky. They include bright favorites like M35 in Gemini, the string of three pretty clusters in Auriga (M36, M37 and M38), and M47 in Puppis that is bright enough to see with your unaided eye. Next door is one of my personal favorites, M46; see if you can detect the faint planetary nebula that lies amongst its splash of a hundred or more stars.
And speaking of planetary nebulae, spring is the perfect time to seek out the Owl Nebula, M97, that hangs just outside of the Big Dipper’s bowl. Viewing its round face and two dark “eyes” does indeed remind one of an owl.
Mars is the only prominent planet in the evening sky. Look for it in the west. While it remains pretty bright, it will appear quite tiny in a telescope. Compare its ruddy color to the two bright reddish stars, Aldebaran and Betelgeuse, and watch as it speeds eastward night to night. At mid-month, Mars forms the apex of an equilateral triangle with the two similarly colored stars.
The hour before dawn is the time to enjoy Saturn and Jupiter. Look for especially pleasing pairings with a crescent moon on April 6 and 7. Saturn is now gaining enough altitude before sunrise to show decently in a telescope. Its magnificent ring system is tilted open more than 17 degrees! Jupiter too, is reaching high enough in the morning twilight to display its colorful system of pastel bands and dark zones.
April will mark the return of “Public Night” at the Patterson Observatory. The Patterson Observatory, located on the campus of the University of Arizona, Sierra Vista, is owned by the University South Foundation and operated by volunteers from the Huachuca Astronomy Club. It has been closed to the public for the past year.
Resumption of the monthly open house observing events at the observatory begins on Thursday April 22 with a hybrid event. Doors open at 7pm. Admission is free, but space is limited for the in-person part of the program, so guests are required to register in advance, on-line, at https://www.universitysouthfoundation.com/patterson-observatory. Telescopes equipped with cameras will deliver live images of the moon and a few deep sky objects. Amateur astronomers will be on hand to describe the objects and conduct laser guided tours of the visible constellations. Patterson’s resident researcher, Tom Kaye, will be available to describe his observing project. He is employing the observatory’s main telescope to make observations in support of NASA’s TESS satellite mission.
The event will be shared virtually as well. Guests can participate over Zoom. You can get your Zoom invitation by emailing firstname.lastname@example.org at least 24 hours in advance.
The event is weather dependent and will be canceled if the sky is cloudy. You can call (520) 458-8278 extension 2214 after 4:30 pm that day to check for a cancelation announcement. For more information, dial extension 2129 during normal working hours to reach the foundation office.
There will be a companion event hosted by the Henry F. Hauser Museum where guests can participate via Zoom from the Mona Bishop Room at the Sierra Vista Library. To kick things off there, HAC member Penny Brondum will deliver a short talk on the constellations starting at 7 p.m. For more information follow the City of Sierra Vista on Facebook or call the Museum at 439-2306.