Friday, February 1
Two of the finest deep-sky objects shine prominently on February evenings. The Pleiades and Hyades star clusters appear highest in the south in early evening but remain conspicuous until well past midnight. The Pleiades, also known at the Seven Sisters and M45, looks like a small dipper to the naked eye. The larger Hyades forms the V-shaped head of Taurus the Bull. Although both look nice without optical aid, binoculars show them best.
Saturday, February 2
Saturn passed on the opposite side of the Sun from Earth exactly one month ago, but it already appears low in the southeast during morning twilight. From mid-northern latitudes, the ringed planet rises about 90 minutes before the Sun and climbs 10° above the horizon a half-hour before sunup. Saturn shines at magnitude 0.6 and should be fairly easy to pick out of the twilight. The waning crescent Moon makes the task even easier this morning. Its 5-percent-lit crescent appears 3° to the ringed planet’s lower left. Simply center the Moon through binoculars and look for the bright point of light near the field’s upper right edge.
For those who believe in folklore, the fate of winter rests on the shoulders of the groundhog. If the furry rodent sticks his head out of his burrow this morning and sees his shadow, we’ll have six more weeks of winter. But if the weather is cloudy, it means spring is right around the corner. What does this have to do with astronomy? Groundhog Day celebrates one of the four so-called cross-quarter days, which mark the midpoints between the solstices and equinoxes. February 2 falls approximately midway between the winter solstice and the vernal equinox.
Sunday, February 3
The variable star Algol in Perseus appears faintest at 11:55 p.m. EST, when it shines at magnitude 3.4. If you start watching it immediately after darkness falls, you can see it dim from its peak brightness (magnitude 2.1) to minimum and then start brightening again. This eclipsing binary star runs through a cycle from minimum to maximum and back every 2.87 days, but the drop from peak brightness and subsequent rise lasts only about 10 hours. Algol appears nearly overhead soon after darkness falls and descends toward the northwestern horizon well after midnight.
Monday, February 4
Venus appears brilliant in the southeast before dawn. It reached greatest western elongation a month ago and continues to dominate the predawn sky. The inner world shines at magnitude –4.3, some 10 times brighter than the second-brightest planet, Jupiter. Venus rises nearly three hours before the Sun and stands 15° high an hour before sunup. The planet lies among the background stars of Sagittarius, close to two of the Milky Way’s finest deep-sky objects. This morning, the Trifid Nebula (M20) lies 2° due south of the planet and the Lagoon Nebula (M8) appears 1.5° farther south. Through a telescope, Venus shows a disk that spans 19" and appears nearly two-thirds lit.
New Moon occurs at 4:04 p.m. EST. At its New phase, the Moon crosses the sky with the Sun and so remains hidden in our star’s glare.
Tuesday, February 5
One of the sky’s largest asterisms — a recognizable pattern of stars separate from a constellation’s form — occupies center stage on February evenings. To trace the so-called Winter Hexagon, start with southern Orion’s luminary, Rigel. From there, the hexagon makes a clockwise loop. The second stop is brilliant Sirius in Canis Major. Next, pick up Procyon in the faint constellation Canis Minor, then the twins Castor and Pollux in Gemini, followed by Capella in Auriga, Aldebaran in Taurus, and finally back to Rigel.
The Moon reaches apogee, the farthest point in its orbit around Earth, at 4:29 a.m. EST. It then lies 252,622 miles (406,555 kilometers) from Earth’s center.