April 1 Through 20 (Saturday-Thursday) Comet 41P Tuttle-Giacobini-Kresak. Maybe Visible Naked Eye. This is the closest approach this short period comet will come to Earth since it was discovered in 1858. That’s the good news. The (maybe) not so good news is this comet is small (less than 1 mile wide) and has been notoriously dim during past flybys. As a matter of fact, I knew this comet was out there but thought it wasn’t bright enough to talk about until March 25 when it was reported brightening to magnitude 7. That’s still too dim to see without binoculars or a telescope, but its light curve suggests that it’ll reach naked eye brightness by April 10. Great news…BUT…there will be almost a Full Moon that night spoiling the view of this comet with its intense glare.
April 11 (Tuesday) Full Pink Moon. We’re just 3 weeks and a day into Spring and expecting the countryside to spring into color. This Full Moon is so named because of the flower pink phlox which is an early Spring bloomer. I’ve been watching the area around Mount Sangre Observatory and noticed crocus blooms on March 10. By April’s Full Moon there should be many more awakening from their long winter sleep.
April and May are great months to study an area in the sky we all know well…or think we do! The famous Big Dipper will be high in the northern sky “upside down” pouring out its celestial brew during prime viewing hours. Let’s get better acquainted with this bright asterism in the constellation Ursa Major The Big Bear. Start with the end of the Dipper’s handle, Alkaid (AL-kade) which is Arabic for, “The leader.” In some Arabic traditions, the Big Dipper represented a funeral train with a coffin carrier or bier represented by the ladle of the Big Dipper. The bier had three mourning maidens (stars in the handle) in front of it. This funeral train was called, “Daughters of the Bier” led by Alkaid. The next star in the handle, Mizar (MYE-zahr), is actually two stars. If you have at least 20/30 vision, you can see both. Mizar means, “girdle” in Arabic and it’s dimmer companion Alcor (AL-kor) means, “the cavalier” or “the rider.” Together, they represent the horse and rider with the “girdle” being the shoulder strap that pulls the weight out of the horse’s front legs. Alioth (AL-lee-oth) means “fat tail of a sheep.” It is part of the tail of the Big Bear which I always found odd since bear tails are short and stubby. Megrez (meg-REZ), “the base,” is the attach point of the bear’s tail on it’s body or the corner of the Big Dipper’s ladle that attaches to the handle. The bottom star of the ladle on the handle side is Phecda (FEK-da) or Phad (FODD) which means “thigh of the bear.” Merak (MER-ak), “the loins” is the other bottom star in the ladle with Dubhe (DOOB-huh), “the back of the Great Bear” marking the location of the top of the ladle on the non-handle end. As you can see, most of these Arabic names refer to the anatomy of a bear. Of course, the Arabic mythology is just one of many stories different cultures told about this most prominent star pattern in the northern hemisphere.
These 8 stars look like they belong together and 6 of them do. Those 6 that generally move through space in the same direction are called the Ursa Major Moving Group and are 58 to 84 light years away from us. The two that don’t belong are at both ends of the Dipper, Alkaid at 101 light years and Dubhe at 124. These two stars are moving in opposite directions and if we could live forever, we would see the bowl and handle of the Big Dipper slowly stretch to an unrecognizable shape as the millennia march on.
April’s eastern horizon has two bright binocular sights to share. The brightest, rising in the ESE, is Jupiter with its entourage of four Galilean Moons. Next, is the Coma Cluster, a loose group of stars forming a V shape reminiscent of a flock of ducks or geese. Your binocs may reveal as many as 40 stars, but because it’s so close (“only” 280 light years away), you may have to scan up, down, and sideways to see them all.
At this specific date and time, you’ll see Jupiter’s 4 Galilean Moons equally distributed two on each side. From left to right will be Ganymede, orange/yellow Io, planet Jupiter, Callisto, and Europa. The bright blue-white star Spica is below Jupiter giving you the impression it’s a distant moon of the jovian planet. The Coma Cluster is near top left center in this image. You should be able to see a dim foggy patch of stars in this location and 20 to 40 individual stars through your binoculars. Bright yellow celestial navigation star Arcturus in the constellation Bootes the Sheep Herder is at the left edge of this picture to help you locate this part of the night sky.
April’s southern sky offers a rare view (about 40 degrees below the celestial equator) of what we can see “down under.” Four southern hemisphere constellations Antlia The Air Pump, Vela The Sail, Pyxis The Ship’s Compass, and Puppis The Poop Deck mark a substantial portion of the southern Milky Way. All of these constellations except Antlia represent parts of the mythical ship Argos which Jason and his Argonauts sailed during their many adventures. I selected the 8 PM view because this marks the highest point these constellations will reach before plunging below the southwestern horizon as the night progresses. This is only 45 minutes after sunset, so evening twilight may interfere with your viewing of the two star clusters I’ve marked (NGC 2451 and NGC 2477) in Puppis. If you wait until 8:30 when the sky will be darker, these two clusters will be lower in the sky, but still worth viewing. There is a bright yellow-orange star (C-Puppis) shining in the middle of NGC 2451 that would be 6,600 times brighter than our Sun if it was the same distance away. NGC 2477 (orange circle) is dimmer and 4 times farther away than NGC 2451, but contains a dense group of 300 stars…at least 12 times as many as NGC 2451.
You’ll have to wait until 8:45 PM MDT for evening twilight to fade so you can see the “farewell tour” of two prominent winter constellations. As Spring progresses, Orion The Hunter and Taurus The Bull will sink lower and lower in the western sky until they are gone completely not to rise again until next winter.
As Michael Keaton said in the hit movie, “Betelgeuse,” “It’s Showtime!” The April night sky features three superclusters of galaxies in Leo, Coma Berenices, and Virgo. Together, they provide a lifetime (maybe longer!) of relatively bright galaxy viewing for the amateur astronomer. We got our first introduction to this enormous collection of galaxies in March when Leo appeared above the eastern horizon. Now, Leo is high in the southern sky at prime viewing hours followed by Coma Berenices. The largest group by far is the Virgo Supercluster rising in the east during April. I’m not sure when you are going to view this deluge of island universes, so I’m listing all three starting with the best to view in the early evening hours followed by those in prominent positions later in the night.
Editor’s Note — Gary Zientara of Taos Pines Ranch near Angel Fire is a former teacher and lifelong amateur astronomer. See more viewing tips at mountsangreobservatory.com.