SUNSET: 
0FRIDAY, FEBRUARY 9
■ After it’s good and dark look due east, rather low, for twinkly Regulus. Extending upper left from it is the Sickle of Leo, a backward question mark. It's about as long as a fist and a half at arm's length.
"Leo announces spring," goes an old saying. Actually, Leo showing up in the evening announces the cold, sloppy back end of winter. Come spring, Leo will already be high.
■ New Moon (exact at 6:59 p.m. EST).
SATURDAY, FEBRUARY 10
■ Many binocular observers check in on the 5th-magnitude open cluster M41 just 4° south of Sirius. But how many then look the other way from Sirius for 6th-magnitude M50? It's 10° north-northeast from Sirius, dimmer, smaller and more subtle than M41.
Find it by sweeping from Sirius first to Theta Canis Majoris, the 4th-magnitude pointy nose of the Big Dog's stick figure, then on again nearly as far in the same direction. It's not exactly easy, but it's there.
M50 is about 2,900 light-years from us; M41 is about 2,300.
For more finding help see Matt Wedel's Binocular Highlight column, with chart, in the February Sky & Telescope, page 43. With big enough binoculars you can also try for the asterism "Pakan's 3" that he plots, closer off Canis Major's nose.
SUNDAY, FEBRUARY 11
■ It's not a big hop from a red supergiant, Betelgeuse, to a red dwarf nearby. Have you ever seen a red dwarf ever? These are the most common stars in space, but they're so intrinsically dim that not one is among the 6,000 stars visible to the naked eye on the darkest nights. One of the nearest and brightest red dwarfs lies just 3° west of Procyon, which is nicely placed left of Betelgeuse. It's Luyten's Star, also known as GJ 273, and at visual magnitude 9.9 it's in range of many small telescopes. Use the finder charts with Bob King's article Catch Luyten's Star.
It's very close to us, 12.3 light-years away compared to Betelgeuse's 650. So it's also a high proper motion star, moving across its celestial backdrop by 3.7 arcseconds per year. A careful visual telescope user might detect its motion in as little as about 3 years, writes King, "depending on its proximity to field stars and the making and breaking of distinctive alignments with other stars." He suggests, "Make an initial observation, note the position in a sketch, map or photo, and then return a couple years later."
You'll need to be good at telescopic star-hopping with a chart. This is an essential skill for any telescope user to develop. See How to Use a Star Chart with a Telescope, and do expect a certain amount of frustration at first. Don't worry, everyone goes through this.
MONDAY, FEBRUARY 12
■ Orion stands his highest in the south by about 8 p.m. Under Orion's feet, and to the right of Sirius, hides Lepus the Hare. Like Canis Major, this is a constellation with a connect-the-dots that really looks like what it's supposed to be. He's a crouching bunny, with his nose pointing lower right, his faint ears extending up toward Rigel (Orion's brighter foot), and his body bunched to the left. His brightest two stars, 3rd-magnitude Alpha and Beta Leporis, form the back and front of his neck.
TUESDAY, FEBRUARY 13
■ By 9 p.m. or so, the Big Dipper stands on its handle in the northeast. In the northwest, Cassiopeia also stands on end (its brighter end) at about the same height. Between them is Polaris.
WEDNESDAY, FEBRUARY 14
■ The Moon and Jupiter shine only about 4° apart this evening for skywatchers in the Americas. They're the two brightest things in the evening sky. Watch them pull closer together as they sink toward the west.
THURSDAY, FEBRUARY 15
■ The Moon, the Pleiades, and Aldebaran form a large flat triangle this evening, as shown below.
■ This evening Algol should be at minimum brightness, magnitude 3.4 instead of its usual 2.1, for about two hours centered on 11:32 p.m. EST; 8:32 p.m. PST. Algol takes several hours to fade beforehand and to rebrighten after. Comparison-star chart.
FRIDAY, FEBRUARY 16
■ First-quarter Moon tonight (exactly first-quarter at 10:01 a.m. EST). Just lower right of the Moon, by about 2° or 3° for North America, spot the Pleiades as shown above. The Moon passes closer by them for Europe. It occults some of them for southern Africa.
SATURDAY, FEBRUARY 17
■ Right after night is completely dark this week, the W of Cassiopeia shines high in the northwest standing almost on end. Near the zenith is Capella.
The brightest star about midway between Cassiopeia and Capella (and a little to the left) is Alpha Persei, magnitude 1.8. It lies on the lower-right edge of the Alpha Persei Cluster: a large, elongated, very loose swarm of fainter stars about the size of your thumbtip at arm's length. At least a dozen are 6th magnitude or brighter, bright enough to show well in binoculars even through the moonlight this evening.
Alpha Per, a white supergiant, is a true member of the group and is its brightest light. It and the rest are about 560 light-years away.
SUNDAY, FEBRUARY 18
■ Canopus, the second-brightest star after Sirius, happens to lie almost due south of Sirius: by 36°. That's far enough south that it never appears above your horizon unless you're below latitude 37° N (southern Virginia, southern Missouri, central California). And near there, you'll need a very flat south horizon.
Canopus crosses the south point on the horizon just 21 minutes before Sirius does. So, when to look? Canopus is due south when Beta Canis Majoris — Murzim the Announcer, the star about three finger-widths to the right of Sirius — is at its highest due south over your landscape. That's about 8 or 9 p.m. now, depending on how far east or west you live in your time zone. Drop straight down from Murzim then.
■ Algol should be at minimum light, magnitude 3.4 instead of its usual 2.1, for about two hours centered on 8:21 p.m. EST.
This Week's Planet Roundup
Mercury is out of sight deep in the sunrise.
Venus, magnitude –3.9, shines low in the southeast during dawn. It's a little lower every morning.
Mars, magnitude +1.3, remains deep in the sunrise.
Jupiter, magnitude –2.3 in Aries, is the bright white dot high in the southwest at dusk; lower in the west-southwest later. It sets in the west by 11 or midnight. In a telescope Jupiter has shrunk to only 38 arcseconds wide.
We've adjusted the contrast of the image to approximate Jupiter's visual appearance. To get a better idea of Jupiter as seen in a telescope at high power, stand far back from your screen and squint a bit.
Saturn, magnitude +1.0, is disappearing into the sunset glow.
Uranus, magnitude 5.7 in Aries, remains 11° upper left of Jupiter. In a telescope at high power Uranus is a tiny but distinctly nonstellar ball, 3.7 arcseconds in diameter. Locate and identify it using the finder charts in the November Sky & Telescope, pages 48-49.
Neptune, magnitude 7.9, is disappearing into the evening twilight.
All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world's mid-northern latitudes. Descriptions and graphics that also depend on longitude (mainly Moon positions) are for North America.
Eastern Standard Time (EST) is Universal Time minus 5 hours. UT is also known as UTC, GMT, or Z time.
Want to become a better astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
This is an outdoor nature hobby. For a more detailed constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential magazine of astronomy.
Once you get a telescope, to put it to good use you'll need a much more detailed, large-scale sky atlas (set of charts). The basic standard is the Pocket Sky Atlas (in either the original or Jumbo Edition), which shows all stars to magnitude 7.6.
Next up is the larger and deeper Sky Atlas 2000.0, plotting stars to magnitude 8.5; nearly three times as many. The next up, once you know your way around, are the even larger Interstellarum atlas (stars to magnitude 9.5) or Uranometria 2000.0 (stars to mag 9.75). And read How to Use a Star Chart with a Telescope. It applies just as much to charts on your phone or tablet as to charts on paper.
You'll also want a good deep-sky guidebook. A beloved old classic is the three-volume Burnham's Celestial Handbook. An impressive more modern one is the big Night Sky Observer's Guide set (2+ volumes) by Kepple and Sanner.
Can computerized telescopes replace charts? Not for beginners I don't think, especially not on mounts and tripods that are less than top-quality mechanically. Unless, that is, you prefer spending your time getting finicky technology to work rather than learning the sky. And as Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand."
If you do get a computerized scope, make sure the drives can be disengaged so you can swing it around and point it readily by hand rather than only slowly by the electric motors.
However, finding a faint telescopic object the old-fashioned way with charts isn't simple either. Learn the tricks at How to Use a Star Chart with a Telescope.
Audio sky tour. Out under the evening sky with your
earbuds in place, listen to Kelly Beatty's monthly
podcast tour of the naked-eye heavens above. It's free.
"The dangers of not thinking clearly are much greater now than ever before. It's not that there's something new in our way of thinking, it's that credulous and confused thinking can be much more lethal in ways it was never before."
— Carl Sagan, 1996
"Facts are stubborn things."
— John Adams, 1770
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