Some daily events in the changing sky for February 5 13.
Friday, February 5
Saturday, February 6
Sunday, February 7
Monday, February 8
Tuesday, February 9
Wednesday, February 10
Thursday, February 11
Friday, February 12
Before dawn Saturday morning (for the Americas), Vesta forms a "double star" with the 7th-magnitude star HD 89930 that changes orientation dramatically every hour. They're within about 1 arcminute of each other when seen before dawn from North America.
Saturday, February 13
Want to become a better amateur astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope. For an easy-to-use 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. Or download our free Getting Started in Astronomy booklet (which only has bimonthly maps).
Once you get a telescope, to put it to good use you'll need a detailed, large-scale sky atlas (set of charts; the standards are Sky Atlas 2000.0 or the smaller Pocket Sky Atlas) and good deep-sky guidebooks (such as Sky Atlas 2000.0 Companion by Strong and Sinnott, the more detailed and descriptive Night Sky Observer's Guide by Kepple and Sanner, or the classic Burnham's Celestial Handbook). Read how to use them effectively.
Can a computerized telescope take their place? I don't think so not for beginners, anyway (and especially not on mounts that are less than top-quality mechanically). 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 and a curious mind." Without these, "the sky never becomes a friendly place."
More beginners' tips: "How to Start Right in Astronomy".
This Week's Planet Roundup
Mercury (magnitude 0.2) is sinking low into the sunrise. Look for it just above the east-southeast horizon about 30 minutes before sunup. Binoculars help.
Venus is hidden deep in the sunset.
Mars, fiery bright at magnitude 1.1, shines in the east-northeast in twilight and higher in the east after dinnertime. It's in Cancer, more than halfway from Regulus below it to Pollux and Castor above it. Mars is highest in the south by 11 or midnight. Binoculars show M44, the Beehive Star Cluster, 3° or 4° roughly to Mars's south.
In a telescope Mars is still 13.8 arcseconds wide; it passed closest to Earth on January 27th and was at opposition on the 29th. The north polar cap has recently faded in brilliance due to dust, as seen at right. Identify other surface features using the Mars map and observing guide in the December Sky & Telescope, page 57.
Jupiter (magnitude 2.0) is descending into the sunset glow low in the west-southwest.
Saturn (magnitude +0.7, in Virgo) rises in the east around 9 p.m. and stands highest in the south around 2 a.m. In a telescope Saturn's rings are tilted only 4.5° from edge-on to us, and they'll narrow further in the coming months.
Uranus is sinking into the sunset.
Neptune is hidden behind the glare of the Sun.
Pluto is low in the southeast before dawn.
All descriptions that relate to your horizon or zenith including the words up, down, right, and left are written for the world's mid-northern latitudes. Descriptions that also depend on longitude (mainly Moon positions) are for North America. Eastern Standard Time (EST) equals Universal Time (also known as UT, UTC, or GMT) minus 5 hours.
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