Monday, February 22
By the time darkness falls this evening, Orion the Hunter is well above the horizon in the south. Beneath him is Lepus the Hare, a lesser-known constellation with several night-sky treasures to explore.
One is the star R Leporis, also called Hind’s Crimson Star for its discoverer, J. R. Hind. It’s located 3.5° west-northwest of magnitude 3.3 Mu (μ) Leporis. This carbon star is one of the sky’s reddest stars, colored such a vibrant ruby by a combination of its low temperature and the absorption of blue light by carbon in the star’s atmosphere. R Leporis is also a
variable star, whose brightness swings over the course of a little more than a year from magnitude 5.5 at its brightest to magnitude 11.7 at its dimmest. You’ll need at least binoculars to spot it, but you’ll certainly notice once you have.
Sunrise: 6:43 A.M.
Sunset: 5:45 P.M.
Moonrise: 12:51 P.M.
Moonset: 3:34 A.M.
Moon Phase: Waxing gibbous (77%)
Tuesday, February 23
Mars slips over the border from Aries into Taurus today; this evening, you’ll find it about 5.5° southwest of the famous Pleiades star cluster (M45). Now just 7" across (and shrinking), Mars is magnitude 0.8. That makes it roughly equal in brightness to Taurus’ alpha star, Aldebaran, which sits among (but is not part of) the Hyades open star cluster sprinkled across the Bull’s nose.
You may notice that Mars and Aldebaran are also similar in color — but their hues come from completely different sources. Aldebaran is a cool red giant star generating its own light, while Mars’ rusty red soil simply reflects light from our own Sun.
Make sure to come back to this region again and again over the next two weeks, as Mars slides south of the Pleiades and then continues its trek across the Bull for several months to come.
Sunrise: 6:41 A.M.
Sunset: 5:46 P.M.
Moonrise: 1:47 P.M.
Moonset: 4:27 A.M.
Moon Phase: Waxing gibbous (85%)
Wednesday, February 24
Let’s visit the brightest star in the Northern Hemisphere sky tonight: Sirius, also known as Alpha (α) Canis Majoris or the Dog Star.
Often depicted as the nose of Canis Major the Big Dog, Sirius’ magnitude –1.4 glow is easy to spot shortly after sunset. The star’s name itself is derived from the Greek word for “searing,” which makes sense for such a searingly bright star! Sirius is intrinsically bright (shining 26 times brighter than the Sun), but it’s so stunning in large part because it is so close to Earth — just over 8 light-years away. In fact, if you were to snag nearby magnitude 0.2 Rigel, Orion’s left knee, and pull it as close to Earth as Sirius sits, it would appear much brighter.
Finally — you may have heard of the Summer Triangle, but have you heard of the Winter Triangle? Sirius is part of this large asterism, together with Betelgeuse in Orion and Procyon in Canis Major’s fellow hunting dog, Canis Minor. You should be able to easily spot all three of these bright stars despite the waxing Moon nearby in Cancer the Crab.
Sunrise: 6:40 A.M.
Sunset: 5:47 P.M.
Moonrise: 2:50 P.M.
Moonset: 5:16 A.M.
Moon Phase: Waxing gibbous (92%)
Thursday, February 25
Cygnus the Swan, high overhead during the warm summer months, is rising before dawn these days. Two hours before sunrise this morning is a perfect time to view one of the most famous double stars in the sky: Albireo (Beta [β] Cygni). Appearing as a single magnitude 3 star to the naked eye, train some optics this way to discover it’s not one, but two stars. They are a wide 34" apart, making them easy to split with even low-powered optics.
One of the most striking things about this system, however, is the stars’ contrasting colors. What colors do you see? Compare the cooler component — which often appears orange or red to observers — with other cool stars, such as Antares in Scorpius or Pollux in Gemini. Likewise, see how you’d rank the hotter component — which may appear blue or white — with nearby Deneb, also in Cygnus, or Vega in Lyra.
Sunrise: 6:39 A.M.
Sunset: 5:48 P.M.
Moonrise: 3:59 P.M.
Moonset: 5:59 A.M.
Moon Phase: Waxing gibbous (97%)
