This Week's Sky at a Glance
Some daily events in the changing sky for February 18 – 26.
by Alan M. MacRobert
Friday, February 18
Look for Regulus about afist-width above the Moon this evening. Regulus marks the bottom-rightend of the Sickle pattern in Leo. It's the bottom of the Sickle'shandle.
Saturday, February 19
This is the time ofyear when Orion stands at his highest due south in early evening. Upperright of him is Taurus with orange Aldebaran and, farther on, thePleiades cluster. Lower left of Orion is Canis Major with bright Sirius.
Late these nights the waning Moon guides the way to Saturn and Spica, while Corvus, the Crow, looks on.
Sky & Telescope diagram
Sunday, February 20
These next two weeks, when there's no moonlight in the sky at the end of twilight, it's a fine time to look for the
zodiacal lightfrom mid-northern latitudes if you have a very clear, unpolluted sky.As the last of twilight is fading away, look for a vague but huge, tall,narrow pyramid of pearly light extending up from the western horizon.It slopes to the left, following the ecliptic, with Jupiter near itsbase. What you're seeing is interplanetary dust near the plane of thesolar system, lit by the Sun.
By about 10:30 or 11p.m. the waning gibbous Moon is well up in the east-southeast. Look leftof it for Saturn, and lower left of it for slightly fainter Spica.They're higher by midnight, as shown at right. The three of them crossthe sky together for the rest of the night to pose in the southwest atdawn Monday morning, as shown at lower right.
The scene for early risers on Monday morning the 21st.
Sky & Telescope diagram
Monday, February 21
Sirius transits themeridian of the sky (i.e. is due south) around 8 or 9 p.m. this week,depending on where you live east or west in your time zone. Sirius isthe brightest star in all the sky (after the Sun). The secondbrightest is far-southern Canopus. By coincidence, Canopus and Siriustransit at nearly the same time. If you live at least as far south asAtlanta, Phoenix, or Los Angeles, see if you can spot Canopus just abovethe south point on your horizon when Sirius is approaching themeridian. (Canopus transits 20 minutes before Sirius.)
Tuesday, February 22
You may know of thefine winter star cluster M41, visible in binoculars about one binocularfield south of Sirius. But what about the cluster M50? Follow a linefrom Sirius to the tip of Canis Major's nose (Theta Canis Majoris),continue nearly as far exactly straight onward, and there you are. M50is magnitude 5.9, quite a bit fainter than M41's magnitude 4.5.
In the same field with M50 is another, fainter cluster: NGC 2343. It's atougher catch at magnitude 6.7. For a finder chart and more about theseobjects, see Gary Seronik's Binocular Highlight column in the February
Sky & Telescope, page 45.
Wednesday, February 23
Have you ever done athorough telescopic explore around the horns of Taurus? Starting withthe Crab Nebula, use French's Deep-Sky Wonders column and chart in theFebruary
Sky & Telescope page 60.
Thursday, February 24
After the last-quarter Moon rises around 2 or 3 a.m. Friday morning,look to its right for Antares and the head of Scorpius. They're high inthe south by dawn, as shown below.
Before and during dawn on the 25th, the Moon hangs with Antares.
Sky & Telescope diagram
Friday, February 25
By 8 or 9 p.m. thisweek (depending on where you live in your time zone), the Big Dipper hasrisen to the same height in the northeast as Cassiopeia has descendedto in the northwest. Their seasonal dominance is reversing; spring is onthe way.
Saturday, February 26
After dinnertime atthis time of year, four big carnivore constellations are on the march ina row from northeast to south. They're all seen in profile with theirnoses pointed up and their feet (if any) to the right: Ursa Major theGreat Bear in the northeast (with the Big Dipper as his brightest part),Leo in the east, Hydra the Sea Serpent in the southeast, and CanisMajor in the south.
Early Sunday morning the asteroid38 Leda occults an 8.7-magnitude star at the Virgo-Centaurus border forup to 31 seconds as seen from a track crossing from southern Mexicothrough Texas to Montana.
Path map, finder charts, and other details.