http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html Skywatchers Diary http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 1 January 2007 Monday, January 1 The Moon is high in the east at nightfall. The bright "Mother goat" star Capella is 18° to Moon's upper left, and Aldebaran, eye of Taurus the Bull and follower of the Pleiades, is 16° to Moon's right. Cover the Moon or use binoculars to see 1.7-mag. Elnath or Beta Tauri, tip of the Bull's northern horn, only 1.2° to Moon's left. From East Lansing, least separation between Moon and Beta Tauri occurs shortly before 9 p.m., when the star appears 0.4° -- less than a moon's width -- north of the Moon's northern edge. The highest Moon this time around occurs at 11:24 p.m. in East Lansing, when it climbs within 15° south of overhead. On Tuesday at 7:43 a.m. (25 minutes before sunrise), the Moon sets 40° north of west; more tomorrow. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 2 January 2007 Tuesday, January 2 This moon-cycle's northernmost moonrise occurs in East Lansing today at 4:06 p.m. (1 hour 10 minutes before sunset), 40° N of E. At nightfall, look for Elnath (Beta Tauri) 13° to Moon's upper left, and the Gemini Twins Castor and Pollux, 4.5° apart, 16° to 18° to Moon's lower left. By 1½ hours before sunup on Wednesday, the Twins are 11° to 13° upper left of Moon, which is then in WNW. From East Lansing on Wednesday, Moon sets 39° N of W at 8:37 a.m., within half an hour after sunrise and just 20 minutes before reaching Full. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 3 January 2007 Wednesday, January 3 The Moon has passed Full, yet it still rises at 5:13 p.m. in East Lansing, almost 38° N of E some 3 minutes before sunset, because the Moon is a few degrees north of the ecliptic or plane of Earth's orbit. At nightfall, look for the Gemini twins Pollux and Castor 4° to 6° to the Moon's left. By dawn's first light on Thursday, they appear in W to WNW, 3° to 8° to Moon's upper right. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 4 January 2007 Thursday, January 4 This month's only evening deep twilight moonrise takes place in East Lansing at 6:24 p.m. (1 hour 7 minutes after sunset), almost 33° N of E and 9° below Pollux, the brighter and lower Gemini Twin. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 5 January 2007 Friday, January 5 Tonight's moonrise occurs in East Lansing at 7:35 p.m., 26° N of E and just over 2¼ hours after sunset. At 10 p.m., face east to find Saturn within 8° below the Moon, and Regulus within 6° lower left of Saturn. By 1¼ hours before sunup on Saturday, they'll all be well up in WSW to W, with Saturn 4° to Moon's upper left, and Regulus within 6° upper left of Saturn. Low in SE, find bright Jupiter with Antares 5° lower right, and faint Mars rising 13° to their lower left, completing an isosceles triangle. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 6 January 2007 Saturday, January 6 Moonrise tonight in East Lansing occurs 19° N of E at 8:42 p.m. By 10 p.m. find Saturn 5° to Moon's upper right, and Regulus about 1° to Moon's lower right. By 1¼ hours before sunrise on Sunday, find Moon in WSW, with Regulus within 3° lower right, and Saturn nearly 6° lower right of Regulus. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 7 January 2007 Sunday, January 7 Tonight one hour after sunset as seen from the latitude of East Lansing (42.7° N), Venus appears only 3° up, 32° S of W, so to be sure to spot this planet, look even sooner after sunset. Using binoculars, look about 6° to 8° upper right of setting Venus to see two 3rd-mag. stars, Beta and Alpha in Capricornus. Tonight, all three are in line. On Monday 1¼ hours before sunrise, locate Moon high in SW with Saturn 21° to its lower right, and Jupiter low in SE with Mars 14° lower left. The four solar system bodies, in order Mars-Jupiter-Moon-Saturn, span 120° Monday morning. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 8 January 2007 Monday, January 8 On Tuesday morning 1¼ hours before sunrise, Jupiter passes 5¼° north of Antares. By early in April, Jupiter widens to 11° ENE of Antares and will begin retrograde. In the following four months, Jupiter will go 10° west against the background, until in the evening sky in August, the giant planet will end retrograde and appear just 5° N of Antares, a little closer than it does now. On Tuesday and Wednesday mornings, faint Mars can be seen 15° E (lower left) of Jupiter. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 9 January 2007 Tuesday, January 9 Four hours after sunset, look low between ENE and E to find Saturn with fainter Regulus within 6° lower left. The gap between star and planet will nearly double by the time Saturn ends retrograde in the April evening sky. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 10 January 2007 Wednesday, January 10 On Thursday 1¼ hours before sunrise, find Spica well up in S, 3°-4° to left of the Last Quarter (half full) Moon. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 11 January 2007 Thursday, January 11 On Friday 1¼ hours before sunrise, look south to find a fat waning crescent Moon with Spica 9° upper right. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 12 January 2007 Friday, January 12 On Saturday 1½ hours before sunrise, look SSE to find the 3rd-mag. star Alpha Librae 5° to Moon's upper left. The star's name, Zubenelgenubi, means "northern claw" of the much larger older version of the Scorpion. The head and heart (Antares) of the Scorpion can be found near bright Jupiter low in SE. Binoculars show Alpha Lib has a 5th-mag. companion star just 4 arcminutes to its upper right. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 13 January 2007 Saturday, January 13 On Sunday 1½ hours before sunrise, locate bright Jupiter low in SE 15° lower left of the Moon. Between Moon and Jupiter find the three bright stars of the Scorpion's head, and just over 5° to Jupiter's lower right find Antares, heart of the Scorpion. Mars, just rising, is best seen by waiting about 15 minutes. Each day against the stars, Mars currently shifts by nearly ¾ degree, and Jupiter by nearly 0.2°. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 14 January 2007 Sunday, January 14 A beautiful sight for unaided eye and binoculars awaits early risers about 1¼ hours before sunrise on Monday: The Moon with Antares just one degree upper left of the northern cusp, or upper point, of the lunar crescent, and Jupiter just over 5° upper left of Antares. Look also for Mars 18° lower left of Jupiter, and Saturn-Regulus just over 6° apart well up in WSW to W. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 15 January 2007 Monday, January 15 The Summer Triangle is equally visible at dusk today and at dawn on Tuesday. Its lowest member, Altair, is low, just N of W at dusk today, and low, just N of E at dawn tomorrow. The other two stars, bright Vega and fainter Deneb, are higher and farther north. Also on Tuesday morning, 1¼ hours before sunrise, find the thin old lunar crescent, southernmost Moon of January, very low in SE, with Jupiter and red Antares 13° upper right, and faint red Mars 9° to Moon's left. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 16 January 2007 Tuesday, January 16 About 30 minutes before sunrise on Wednesday, or 7:35 a.m. EST from East Lansing, use binoculars to find the thin old crescent Moon 39.4 hours before New but just 1°-2° up in SE and 26° lower left of Jupiter. This is a difficult sighting from northern states! From southern states it's easier because the Moon rises earlier, in a darker sky. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 17 January 2007 Wednesday, January 17 Just over three hours after sunset, find the Pleiades star cluster at its highest point in the sky, within 20° S of overhead in East Lansing. The cluster reaches the same position in the sky nearly 4 minutes earlier each day because of the Earth's revolution around the Sun. In late April, the Pleiades will appear low in WNW at dusk, and around May 20-21 will be on the far side of the Sun and not visible from Earth. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 18 January 2007 Thursday, January 18 The Moon is New today at 11:01 p.m. EST (8:01 p.m. PST), in conjunction with the Sun and not visible today. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 19 January 2007 Friday, January 19 Fifteen minutes after sunset, if the sky is very clear and transparent, find Venus low in SW (from E. Lansing, it's 13° up and 37° S of W), then use binoculars to find Mercury only 2° or 3° up and 12° to Venus' lower right. In East Lansing, the time is 5:49 p.m. EST, and a very thin crescent Moon, age 18.8 hours, appears just 2° to Mercury's left. From southern California, the Moon is higher and easier, 2°-3° upper left of Mercury and at an age of over 21 hours. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 20 January 2007 Saturday, January 20 One hour after sunset, the first easy young crescent Moon is low in SW to WSW, with Venus 2°-3° to its lower right. Binoculars may show 3.7-mag. Gamma Capricorni within 1.3° upper left of Venus, and 2.8-mag. Delta Cap (tail of Sea-goat) within 1.8° upper left of Gamma, from locations where Delta isn't then being covered by the Moon. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 21 January 2007 Sunday, January 21 Within 30 minutes after sunset, find Moon in SW and look for Venus 15°-16° to its lower right, and for Mercury setting 11° lower right of Venus. Tonight, Saturn rises as Venus sets. On what date will you first see both Venus and Saturn simultaneously? http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 22 January 2007 Monday, January 22 Binoculars show 3rd-mag. Delta Capricorni, tail of Sea-goat, 1° south (lower left) of Venus as sky darkens. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 23 January 2007 Tuesday, January 23 Low in SW to WSW thirty minutes after sunset today and Wednesday, binoculars show Mercury 10° lower right of Venus. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 24 January 2007 Wednesday, January 24 Low in E three hours after sunset, look for bright Saturn with Regulus, heart of Leo, 7° lower left. About 1¼ hours before sunrise on Thursday, Saturn in W and bright Jupiter in SE are 110° apart. Mars, within 24° to Jupiter's lower left, is passing within 1.6° N (upper left) of 3rd-mag. Lambda Sagittarii, top star of the Teapot. Use binoculars to see the star, very low in morning twilight. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 25 January 2007 Thursday, January 25 About 30-40 minutes after sunset, look very low in WSW for Mercury 9° lower right of Venus. At nightfall, the First Quarter Moon, half full, is high in SSW with 2nd-mag. Alpha in Aries 6°-7° to its north. High in S, 18° lower left of Moon, is the 2.5-mag. star Alpha in Cetus. Look for 3.5-mag. Gamma Ceti 5° W (right) of Alpha, and next for 4.1-mag. Delta 3° SSW (lower right) of Gamma. In the coming weeks, keep watch for the star Mira (Omicron Ceti), 6° SW (lower right) of Delta. It's a long-period variable star, which changes in brightness, usually between 3rd and 9th magnitude and back again in a cycle of about 11 months. Mira is due to reach peak brilliance in early March 2007, when it will still be visible, low in WSW at nightfall. For more information and a finder chart showing Mira's position with magnitudes of suitable comparison stars, go to www.aavso.org/observing/charts and enter "omi Cet", and then choose the A (brighter) or B (fainter) chart. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 26 January 2007 Friday, January 26 Tonight, just before twilight ends, Venus and Saturn are 174° apart and not quite 3° above opposite horizons. Can you see both simultaneously? (In East Lansing, MI, the best time tonight is 7:14 p.m. EST, about 1½ hours after sunset.) Keep track of these two planets until their conjunction on June 30, when they'll be just 0.7° apart. In the morning sky on Saturday, 1¼ hours before sunrise, the three bright outer planets Mars-Jupiter-Saturn, span 135°. More tomorrow. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 27 January 2007 Saturday, January 27 At nightfall, look for the Pleiades star cluster 4° west of the Moon, and Aldebaran, eye of Taurus, 12° below the Moon. About 1¼ hours before sunrise on Sunday, in SE sky, find bright Jupiter with Mars 25° lower left. Antares, heart of Scorpius, is now over 6° to Jupiter's lower right. Saturn is in W, with Regulus, heart of Leo, over 7° to its upper left. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 28 January 2007 Sunday, January 28 About 45 minutes after sunset, look low in WSW for Mercury 8° lower right of Venus. All this week is excellent for viewing the innermost planet of our solar system. At nightfall, note the 1.7-mag. star Elnath (tip of Bull's northern horn) within 5° E (lower left) of the Moon. The Moon approaches this star through the night, until the northernmost Moon sets 40° N of W in East Lansing at 5:34 a.m. Monday, nearly 2.4 hours before sunrise. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 29 January 2007 Monday, January 29 Today's northernmost Moon in East Lansing rises 40° N of E at 1:55 p.m., nearly 4 hours before sunset, and reaches its highest point, within 15° S of overhead, at 10:14 p.m. Tonight the Moon is near the feet of Gemini and nearly 5° north of the northernmost point of the Sun's apparent annual journey among the stars. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 30 January 2007 Tuesday, January 30 Watch the Moon approach the Gemini Twin stars Pollux and Castor from dusk tonight until dawn on Wednesday. http://www.pa.msu.edu/abrams/SkyWatchersDiary/Diary.html 31 January 2007 Wednesday, January 31 Within an hour after sunset, look low in WSW for Mercury 7° lower right of Venus. Saturn is just rising in ENE. In order from horizon to horizon, four solar system bodies, Mercury-Venus-Moon-Saturn, span 175°.