The sky: February 18-25; Venus and Mars in close conjunction early on the 22nd

Special to, February 18, 2024

Excerpts from weekly Sky&Telescope report.


■ 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.

■ 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.


■ Face southeast after dark. The bright gibbous Moon shines about midway between Procyon below it and brighter Capella near the zenith.

To the right of the Moon, Aldebaran and the Pleiades stack themselves above Orion.

Much closer to the Moon’s left or lower left are Pollux and, above it, slightly fainter Castor.


■ The waxing gibbous Moon shines close to Pollux this evening, while Castor watches from a little above. Binoculars help through the moonlight.


■ Not long after dark, the Big Dipper, standing on its handle, is as high in the northeast as Cassiopeia has descended to in the northwest. Cas also is standing on end. The wheel of the year is turning.

■ A dawn challenge. Venus and Mars are in conjunction Thursday morning, just above the east-southeast horizon when dawn is brightening as shown below. About 40 minutes before sunrise, pick up Venus only a few degrees above the true horizon. Then, use a telescope to try for the tiny orange fuzzblob of Mars 0.6° to Venus’s lower left. Good luck. Mars is only 1/120 as bright!

Venus and tiny, faint, difficult Mars will be in close conjunction just above the east-southeast horizon as dawn brightens Thursday morning. (The visibility of the faint objects in bright twilight is exaggerated.)


■ The Moon this evening forms an isosceles (two sides equal) triangle with, to its lower left, two stars of Leo: Regulus and lesser Gamma Leonis (Algieba).


■ Full Moon tonight (exactly full at 7:30 a.m. Saturday morning EST). At sunset the Moon is already rising in the east. By nightfall you’ll see that the Moon is almost straight between Regulus 3° to its right and lesser Gamma Leonis 5° to the Moon’s left. Binoculars will help you spot them through the moonlight, especially if there’s any haze in the sky.


■ Have you ever tried for Sirius B, the famous white dwarf? Sirius A and B are now at the widest apparent separation of their 50-year orbit, 11 arcseconds apart, and will remain so for the next couple years before they start closing up again. You’ll want at least an 8-inch telescope (preferably larger), a night of really excellent steady seeing (keep checking night after night; the seeing makes all the difference for spotting Sirius B), extreme high power, and Sirius standing at its highest like it is now.

The Pup is east-northeast of the Dog Star and 10 magnitudes fainter: one ten-thousandth as bright.


■ It’s not spring for another month, but the Spring Star Arcturus seems eager to thrust itself into view. It rises above the east-northeast horizon around 8 or 9 p.m. now, depending on your latitude.

To see where to watch for this, find the Big Dipper as soon as the stars come out; it’s high in the northeast. Follow the curve of its handle down and around to the lower right by a little more than a Dipper-length. That’s the spot on the horizon to watch.

By 10 or 11 p.m. Arcturus dominates the east.

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