Evan Hazard, Northland Stargazing: Planets, major constellations, and bright stars
Assume February will be cold. Dress warmly; you get cold faster when you are not moving briskly.
In the SSW, Mercury reaches greatest brilliancy after sundown Feb. 10 and continues to increase its apparent distance from Sol until greatest elongation Feb. 16, one of three or four good apparitions in 2013. Much dimmer Mars is in the neighborhood, ⅔ degrees to Mercury’s upper left Feb. 7 and ⅓ degrees lower left of Mercury on Feb. 8. Use binoculars.
Jupiter dominates the evening sky, dimming as we recede from it, but still is the brightest evening planet. Saturn graces the wee hours, rising after midnight on Groundhog Day but by 10:30 p.m. March 1, St. David’s Day. (St. David is the patron saint of Wales. Venus is low in the ESE at month’s start, but soon disappears in Sol’s glare.
Venus will still be visible before dawn in early February, but will soon disappear into Sol’s glare. It will peek into our evening sky in September.
Roughly NNE of Jupiter, almost directly overhead February evenings, is a bright star we’ve not mentioned often. Just north of the zenith, it’s Capella, brightest star in Auriga, the “Charioteer.” Auriga is, for us this far north, a circumpolar constellation, skimming along our northern horizon in summer. (About charioteers, go to www.snopes.com/history/american/gauge.asp for analysis of the story that our standard railroad gauge is based on the width of the rear ends of the two horses that pulled Roman chariots.)
Capella, only 42.2 light years away, is the 11th brightest true star. It looks like a single star, even in binocs, but is actually a system of four stars, two binary pairs. The brighter two, each over twice the mass of Sol, revolve around their common center of gravity about 0.75 astronomical units (AU) apart. (One AU = the average Earth-Sol distance.) The other two are dim red dwarfs, revolving around each other and around the bright pair some 10,000 AU away.
February constellations are splendid. Familiar Orion this month is at its highest, almost due south, Taurus with its open clusters, the Hyades and Pleiades is SSW of the zenith, and, to the east of Auriga and Orion are Gemini, Canis Minor, and Canis Major (with Sirius, the brightest true star). Ursa Major is high in the NE, and Leo has risen in the ENE.
Cassiopeia, another circumpolar constellation, is high in the NW. The “Great Square” in Pegasus is still up above the WNW horizon, and Perseus, containing the best known eclipsing variable, Algol, is just above it. Three “minima of Algol” are 1:33 a.m. Feb. 10, 10:23 p.m. Feb. 12, and 7:12 p.m. Feb. 15.
EVAN HAZARD also writes “Threescore and Ten” for The Pioneer’s “Prime Time.”