Backyard Stargazer April 2018
By Francis Parnell
After a few months as the “morning star”, Venus returns to the western sky for the next six months as the brilliant “evening star.” It’s called the twin of Earth, but with 90 times the atmospheric pressure, sulfur dioxide clouds with sulfuric acid droplets, and a surface temperature of 864-degrees, it’s the poster planet for the runaway greenhouse effect. Earth is warming; Venus warns us of what a greenhouse effect can do.
Looking low in the southeast just before dawn on the 2nd, and above the Teapot of SAGITTARIUS, the Archer, the ringed planet Saturn and red Mars are at conjunction, separated by only 1.3-degrees. Scan to the right toward the Moon and spot bright Jupiter in LIBRA, the Scales. The waning crescent Moon joins the pair on the 7th, when all of them will be visible in a standard binocular field of view. When we look towards Sagittarius, we’re looking towards the center of the Milky Way galaxy, 25,000 light-years away.
Looking west on the 17th at dusk, the waxing crescent Moon is 6-degrees to the left of sparkling white Venus.
At sunset on the 18th, the thin sliver of the waxing crescent Moon is in the “V” of the Hyades, an open cluster of stars that make up the face of TAURUS, the Bull. Aldebaran, the eye of TAURUS, is less than 2-degrees to the upper left of the Moon. The Hyades are 151 light-years away; Aldebaran only 67 light-years distant. It’s a chance alignment.
Eventually, Aldebaran’s space motion will carry it away from the Hyades and the “Bull” will lose its eye!
On the 22nd, the 1st quarter Moon is in CANCER, the Crab, about 3-degrees below the Beehive Star Cluster (M44), an open star cluster that’s 590 light-years away. It’s called the Beehive Cluster because it sort of looks like a bunch of bees around a hive. Use binoculars for a good view of M44.
From the 22nd through the 28th, Venus is within 5-degrees of the Pleiades (the seven sisters), a beautiful open star cluster in TAURUS, the Bull. On the 25th, the separation is only 3.5-degrees. Binoculars will give a great view! Many people that aren’t familiar with the night sky mistakenly identify the Pleiades as the “Little Dipper.” Actually, the Little Dipper is in the northern sky, and is a circumpolar constellation better known as URSA MINOR, the Little Bear. The end star in the handle of the Little Bear is Polaris, the North Star. It’s a Super-giant star, 45 times the solar diameter, 430 light-years away, and 2,500 times the Sun’s luminosity.
After sunset on the 24th, spot the waxing gibbous Moon 3-degrees to the left of Regulus, the brightest star in LEO, the Lion, as the two travel westward together.
In LIBRA, the full Moon and bright Jupiter vie for our attention on the night of the 30th.
You can tell light pollution is bad when you can see your hometown from space, but you can’t see space from your hometown. Let’s reduce light pollution and “Keep looking up!”
Francis Parnell of Darlington has been an amateur astronomer for over 46 years, and was on the staff and helped out at the Francis Marion University Observatory from 1982 until 2006 by showing visitors “what’s out there.” With the help of a friend, Mr. Ernest Lowry, he built his own telescope in 1986. And, because of light pollution, for the last 31 years he has been advocating for the advantages of using fully-shielded lighting at night.
