February 2009 (update 1)
Skywatcher’s Guide for February 2009
HIGHLIGHTS: Venus is especially prominent this month as our evening planet (the ‘evening star’) above the west-southwestern horizon and is beautifully grouped with the Moon on Friday February 27, a great time to spot Venus in the daytime: Flandrau will host informal viewing of the Moon and Venus (Friday, Feb. 27) starting that day at 5:30 p.m. Also, the stars of the winter sky shine highest and brightest on February evenings, making this month one of the best for stargazing, especially from the Desert Southwest.
PLANETS
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Brilliant Venus, the brightest star like object in the sky, is now near peak altitude above the west-southwestern horizon. White Venus reaches 35 degrees above the west-southwestern horizon about 45 minutes after sunset in early February. On the evening of Friday February 27, the 3-day-old waxing crescent Moon is beautifully grouped near Venus in the western evening twilight. This presents a rare occasion where Venus can be easily spotted in the daytime, because the Moon is near it in our sky. Flandrau will therefore host an informal viewing of the two at our observatory that day, starting with viewing Venus in the daytime at 5:30 p.m. (click for more information). The Moon will lie above Venus the following evening, February 28.
Saturn rises earlier and creeps higher above the eastern horizon and, once it rises, is visible all night long. Saturn is getting closer to its opposition date on March 8, when it is opposite from the Sun in the sky and rising at sunset. The rings of Saturn appear razor thin, as we view them edge-on from Earth, but the angle of tilt starts to noticeably increase this month. Saturn rises at around 9 p.m. in early February, by 8 p.m. in middle February and by 7 p.m. in late February. Around Tucson, Saturn may not clear area mountains until 10 or 20 minutes after these times. You may also look for Saturn at the start of and through much of the morning twilight above the western horizon. Saturn appears as a cream-white, bright star like object of 1st magnitude in brightness. Saturn is located in the constellation Leo the Lion, well below and east its bright star Regulus, which is the bottom of the star pattern called the ‘sickle’ of Leo. The 17-day-old waning gibbous Moon is found well below and nearest Saturn in our sky after it rises around 8:30 p.m. on February 10 and into Wednesday morning, February 11.
Bright Jupiter is lost in the glare of the Sun for much of the first half of the month. By February 14 Jupiter will start to reappear in the morning sky where it can be found well below fainter Mercury and grouped with very faint orange-reddish Mars very low, just 2-3 degrees above an unobstructed east-southeast horizon, 30-35 minutes before sunrise. You’ll need binoculars to see Mars, the two will be tightly grouped, just 0.4 degrees apart, on February 17. The three planets are then beautifully grouped with the razor thin waning crescent Moon on the mornings of February 22 and 23, with the Moon above Mercury on February 22 and below Mars on February 23. Bright Jupiter, as it creeps higher in the dawn, tightly groups with fainter Mercury on February 23 and 24 as well: the two will be just 0.5 degrees apart. Mercury will appear as a zero magnitude star like object, or about as bright as the brighter stars in the sky.
Visitors to Flandrau’s 16-inch observatory telescope should note that of the planets, Venus will be easily visible in the telescope but only for about 30-45 minutes starting when the telescope normally opens at 7 p.m. Other celestial objects, including the Great Orion Nebula, will be shown in the telescope, weather permitting. Flandrau’s main building is now closed on Thursday nights due to state budget cuts but the telescope remains open for viewing during public hours from 7-10 p.m., weather permitting, Wednesday through Saturday nights (excluding select major holidays). Finally, remember that in spotting planets there is a general rule: ’stars twinkle, planets don’t’. This is because stars are point sources of light; therefore starlight is easily disturbed and shifted by air currents in the Earth’s atmosphere. However when looking at Mercury or Mars right now, note that they may appear to twinkle somewhat; This twinkling is of a slower nature than that of the bright stars.
Comet Lulin
Comet Lulin, discovered at the Lulin Observatory in China in 2007, will move into the evening sky and will be visible in binoculars and good quality wide-field telescopes starting February 20, when it may be as bright as fourth magnitude. The comet was closest to the Sun on January 14, 2009 but will pass only 0.41 AU (about 38 million miles) from Earth on February 24, 2009. The comet should be an interesting object for the public to view but will probably not be easily visible from city locations. However The Flandrau Observatory Hyperstar imaging system should easily reveal the tail of this comet and any anti-tail if visible, giving the best view. Comet Lulin will be shown in Flandrau’s Observatory during the special viewing event on Friday, Feb. 27.
Comet Lulin will be visible in the Flandrau Observatory starting February 21 at around 9:50 p.m. and after 8:15 p.m. starting February 25, 2009, when it may appear brightest (being closest to Earth).
Zodiacal Light Visible
February is the best month, and Arizona is a superb place, to look for the Zodiacal Light in the western evening sky, starting 75 minutes after sunset. The Zodiacal Light is sunlight reflecting off of meteoritic dust in our solar system. Because this dust lies along the plane of the solar system, we see its faint glow as a cone of light along the constellations of the Zodiac. Often confused with light pollution or twilight, the Zodiacal Light must be seen on clear moonless nights, in dark locations far away from city lights. In February look for the faint colorless cone shaped glow of the Zodiacal Light to reach high up from the western horizon towards the Pleiades, or ‘Seven Sisters’ star cluster.
FEBRUARY EVENING STARS
 The winter sky as seen facing south in early Feb. around 9:30 p.m, in mid-Feb. at 8:30 p.m. and in late February at 7:30 p.m.  The southern-most winter sky as seen facing south on February evenings  The northern sky between 8:30 and 9:30 p.m. in early to middle February. |
From dark southwestern skies in early February look high above the southern horizon and overhead for the bright stars of winter (and the faint winter Milky Way) at around 8-9 p.m. Orange Betelgeuse, the shoulder of Orion the Hunter, shines left of Orion’s 3 glittering belt stars. Bright blue-white Rigel shines to his belt’s lower right. Below Orion is the smallish constellation Lepus, the Hare. The Gemini Twins, the bright stars Castor and the slightly brighter Pollux twinkle left of Orion. Look for the bright star Procyon (whose name means “Before the Dog”) right or southwest of Jupiter. From Tucson’s latitude the Dog, that is the “Dog Star” Sirius, the brightest star in all the heavens, rises almost at the same time as Procyon, so Procyon’s name isn’t so true this far south. Sirius can be easily found by taking Orion’s belt down or south to Sirius. Watch for brilliant Sirius to flicker different colors dramatically when low in the sky, a wonderful sight in binoculars. The flickering is due to Earth’s atmosphere.
The winter Milky Way can be seen, but only from dark skies far away from city lights, as a faint band of light starting south and east of Sirius and cutting clear across the sky north of Gemini into Auriga, the Charioteer. Very low in the south, when Sirius is highest, find the 2nd brightest star in all the night sky: Canopus. Canopus, twinkling dramatically and with vibrant colors, is only briefly visible and is not seen from most portions of the United States.
The Big Dipper is easy to find rising every February in the late evening sky. Look for the Big Dipper above the northeastern horizon 3 hours after sunset (early in the month), and 90 minutes to 2 hours after sunset late in February. Take the two ends stars off of the bowl (the Pointer stars Dubhe and Merak) and point to Polaris, the North or Pole Star. Polaris is a star of ordinary brightness, and marks the end of the handle of the Little Dipper. Polaris is a direct indicator of latitude and so is always found the number of degrees above the northern horizon equal to an observer’s latitude. In Tucson look for Polaris about 30 degrees (or 3 fists) above the northern horizon. Polaris stays put in the sky, so to the eye it doesn’t appear to move. This is because Earth’s axis is pointed toward Polaris in space.
MOON PHASES
The first quarter Moon will occur on Monday evening, February 2. The Moon on Feb. 4 lies at the edge of the Pleiades cluster, a beautiful sight in binoculars. The February Full Snow Moon rises on the evening of Sunday, February 8 and sets on the morning of Monday, February 9. Last quarter Moon occurs on Monday morning February 16, and the new moon is on Tuesday, February 24.
Note: Additional information can be accessed by phone at Flandrau Science Center’s Astronomy Newsline at (520) 621-4310 or as a menu option at 621-S-T-A-R.
Graphics done using Starry Night Pro and Adobe Photoshop. To purchase Starry Night Pro go to http://www.StarryNight.com