Venus, Mars & Jupiter, February 27, 2015

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Brilliant Venus shines from the western sky this evening with Mars nearby. Venus is now well past Mars. The planets are now nearly 3 degrees apart and separating by about 1 degree each day.

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At the same time, Jupiter shines from the eastern sky.  It appears about 15 degrees to the upper right of the star Regulus.

More posts about the planets:

Mars and Venus, February 2015

Venus as an Evening Star

Jupiter at opposition

Venus, Mars & Jupiter, February 17, 2015

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Brilliant Venus and Mars shine from the western sky this evening.  Venus is moving higher in the sky, as Mars is slowly moving toward the sun’s brilliance.  They are closest this weekend.  Tonight they are less than 2 degrees apart.

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Meanwhile, bright Jupiter shines from the eastern sky at the same time as the planetary pair move together in the west.  It is 14 degrees above the star Regulus.  Just past opposition, Jupiter is in the sky throughout the night, in the east during early the early evening, south around midnight, and west in the predawn hours.

More posts about the planets:

Mars and Venus, February 2015

Venus as an Evening Star

Jupiter at opposition

Venus and Mars, February 2015

As Jupiter gleams in the eastern evening sky as it has just passed opposition, brilliant Venus and Mars pass in the western evening sky during late February. The Venus-Mars pair is closest on February 21.

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During the next few evenings, as the sky darkens, look westward.  Venus is the brilliant “star” in the western sky.  It outshines all planets and stars in the sky.  Its intensity can be easily mistaken for distant airplane lights.  Dimmer Mars is to the upper left of Venus.  On the chart above on February 15, the pair is separated by about 3 degrees, that’s about 6 full moon diameters.

In astronomy we describe the separate between celestial object in the angular measurement of degrees, like those on a protractor.  The diameter of the full moon is nearly 0.5 degree.  Hold up your hand and extend your arm.  At arm’s length the finger nail on your pinky finger covers about the area of the full moon.

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A few nights later (February 18), Venus appears higher in the sky and closer to Venus.  On this evening, the pair is separated by about 1.5 degrees (3 full moon diameters).

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On February 20, a thin crescent moon joins the pair making a spectacular celestial sight.  In this evening, Mars is about 0.75 degrees above Venus with the Moon 1.5 degrees to the right of Venus.  (The moon is exaggerated in size in these images.)

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On the next evening, the pair is separated by less than one full moon diameter with the moon 13 degrees to the upper left of the planetary pair.  The two planets look near each other from the view of our home planet. although they are about 75 million miles apart, over 300 times the earth-moon distance.

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A few nights later (February 25), Venus is nearly 2 degrees to the upper left of Mars.

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By month’s end, Venus continues to climb higher in the sky, about 3 degrees to the upper left of Mars on February 28.  Mars slowly disappears into the sun’s glare as it heads toward conjunction with the sun in mid-June.  Venus continues to climb higher into the sky during the spring.  Later in the summer, Venus leaves the evening sky and reappears in the eastern morning sky.  The pair appears each other in early September, although they are separated by about 9 degrees.

Jupiter at Opposition , 2015

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Jupiter reaches opposition on February 8, 2015.  This occurs when our faster moving planet Earth moves between Jupiter and the sun, making the sun and Jupiter appear on opposite sides of the sky.  At this year’s opposition, Jupiter is 400 million miles from the us.  While it is much larger than Venus, Jupiter’s greater distance makes it dimmer than Venus, currently shining in the southwest during early evening twilight hours.  Venus appears nearly 3.5 times brighter than Jupiter, and outshining all other starlike objects. The chart above shows Earth between Jupiter and the sun.

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Early in the evening look for Jupiter in the eastern sky.  The dimmer stars to the left of the planet make the constellation Leo.  The “Sickle of Leo,” a nickname for some of the stars in the constellation, resemble a farmer’s tool.

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By midnight, Jupiter and the accompanying stars appear high in the southern sky.  Bluish Regulus is part of the view.

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By early morning, Jupiter and its stellar entourage appear in the western sky.  As the sky brightens with the sun rising in the east, Jupiter sets in the west — opposition.

January 2015 Sky Watching

 Sun

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Days continue to lengthen after the December solstice.  The shaded area of the chart above (click it to see it larger) shows the amount of daylight in January compare to the entire year, the red curve.  Daylight increases by nearly 50 minutes during January; by month’s end the sun is in the sky for 10 hours.  (The chart is calculated from U.S. Naval Observatory data)

Earth at Perihelion

The Earth reaches its closest point to the sun on January 4 at 1  a.m. in its slightly eccentric solar orbit.  The perihelion distance is about 3% closer to the sun than it is at its farthest point (aphelion) on July 6.

Moon Phases

NASA Photo

NASA Photo

Phase Date/Time Moonrise Moonset
Full Moon 01/04/15 (10:53 p.m.) 4:34 p.m. 7:14 a.m. (01/05)
Last Quarter 01/13/15 (3:46 a.m.) 12:08 a.m. 11:26 a.m.
New Moon 01/20/15 (7:14 a.m.) 6:55 a.m. 5:28 p.m.
First Quarter 01/27/15 (10:48 a.m.) 11:24 a.m. 1:38 p.m. (01/28)
Times are Central Standard Time for Chicago, Illinois, from US Naval Observatory calculations. (For mjb)

Evening Sky

Four bright planets appear in the evening sky during January.  Mercury, Venus, and Mars appear in the southwestern sky during evening twilight.

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Early in the month Mercury appears near Venus.  When visible, Mercury appears near the horizon and only during twilight.  From Earth, it is never seen in a dark sky.  Venus and Mercury are emerging out of the sun’s glare.  Use Venus to locate Mercury  on days around January 10.  The chart above shows the pair on January when they are less than one-half degree apart with Mars about 20 degrees to the upper left of them.

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Late in the month, the moon passes the western sky planets.  On January 21, it appears with Venus and Mercury, with the two planets separated by about 9 degrees with Mars about 13 degrees to the upper left of the trio.  On January 22, the moon 4 degrees to the right of Mars.  On the next evening the moon is 12 degrees to the upper left of the Red Planet.

Meanwhile, Jupiter rises in the east around 8 p.m. early in the month,

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Jupiter shines from in front of the stars of Leo with its bright star Regulus.  The head of the lion figure in the stars resembles a backwards question mark and is commonly known as “The Sickle.”  The chart above shows Jupiter and Leo on January 10, when Jupiter and Regulus are 9 degrees apart.

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On the night of January 7/8, the moon appears  near Jupiter and Regulus.  The chart above shows them at 2 .m. (January 8) when they appear in the southern sky,

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During the night, Jupiter appears to move westward, as our planet rotates.  The chart above shows Jupiter and Leo high in the western sky at 4 a.m. on January 15.

 Morning Sky

As Jupiter shines from the western sky  in the mornings of January, Saturn climbs into the southeastern sky.

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This Ringed Wonder shines from in front of the stars of Scorpius, with its bright star Antares.  On January 8, appears about 10 degrees above the star.

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On January 16, the crescent moon appears near Saturn.

Comet

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Comet Lovejoy brightens during the evenings of January.  While comets rarely “burn bright,” this one is brighter than most.  Some observers have reported seeing the comet without optical assistance after they first found it with binoculars.  The chart above shows the comet on the evening of January 15 when it is near Aldebaran and the Pleiades.  Look for it with binoculars.  It appears as a fuzzy mass with a concentrated center.  A fuzzy tail may extend to the east.  Once found with binoculars, look for it with your eyes alone without the help of the binoculars.

Sky Watching December 2014

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The chart above shows the hours of daylight during the year (the red line). The blue shaded area shows the daylight hours during December. (Calculated from data from the U.S. Naval Observatory.)

December, the month of the shortest daylight hours, is upon us.  The day with the longest daylight is  December 1 with 9 hours, 22 minutes in the Chicago area.  The daylight hours decrease (9 hours, eight minutes) until the winter solstice.  The sun reaches is farthest south point on December 21 at 5:03 p.m. CST.  At this time the sun is overhead from 23 degrees south of the equator in the Pacific Ocean, at the Tropic of Capricorn.  By month’s end the daylight hours begin to lengthen (9 hours, 11 minutes) as the sun appears farther north during our planet’s annual journey around the sun.  We have lost 6 hours, 5 minutes of daylight since the summer solstice in June, the peak on the graph above.  (Click the images to see them larger.)

Moon

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NASA Photo

Phase Date/Time Moonrise Moonset
Full Moon 12/06/14 (6:27 a.m.) 4:57 p.m. 7:47 a.m. (12/07)
Las Quarter 12/14/14 (6:51 a.m.) 11:27 p.m. (12/13) 11:56 a.m.
New Moon 12/21/14 (7:36 p.m.) 7:27 a.m. 5:33 p.m.
First Quarter 12/28/14 (12:31 p.m.) 11:34 a.m. 12:30 a.m. (12/29)
Times are Central Standard Time for Chicago, Illinois, from US Naval Observatory calculations. (For mjb)

Evening Sky

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Jupiter is the bright “star” low in the east-northeast near midnight as the year’s final month opens.  It is about 7.5 degrees to the upper right of Regulus the brightest star in the constellation Leo.  At this hour, the head of the lion appears to the left of Jupiter.  Known to sky watchers as the “Sickle,” the star pattern resembles a backwards question, although it is named for the cutting tool used in agriculture.

By 5 a.m. Jupiter and Regulus are high in the southern sky.  On about August 22 each year, the sun appears to pass about 1/3 degree below Regulus.  Because the solar system is largely a plane, like that of a pancake and the bright planets move near the plane, the sun, moon and bright planets regularly appear near Regulus.  Regulus, along with several other stars, are signposts of the solar system.

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On December 12, the moon clusters with Jupiter and Regulus.  As explained above, this trio appears high in the south before sunrise.  On this evening, Jupiter is about 7.5 degrees to the upper right of Regulus and 6 degrees to the upper left of the moon.

By month’s end Jupiter rises in the eastern sky around 8 p.m. and shines in the sky during the rest of the night.

Venus begins its evening apparition (appearance) this month.  On December 1, it sets only 30 minutes after sunset and remains hidden in the sun’s glare.

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The brilliant planet appears low in the southwest during bright evening twilight at mid-month.  Depending on the clarity of the sky and the horizon, the first observation of Venus depends on local circumstances at mid-northern latitudes.  Venus and separated by about 30.5 degrees on the chart above which is about 35 minutes after sunset.

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The moon appears above (11 degrees) Venus on December 23rd during twilight.

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On the next evening, as shown on the chart above, the moon appears 6 degrees to the right of Mars.  Venus and Mars are about 28 degrees apart.  The planets continue to appear closer together in the western sky as the new year opens.  They appear closest in late February 2015.

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Mercury joins Mars and Venus in the western sky late in the month.  On December 31, Mercury is 3 degrees to the lower right of Venus and Mars is 24 degrees to the upper left of Venus.

For more about Venus’ evening apparition, see this article.

Morning Sky

With Jupiter rising later in the evening, it rises higher in the sky each hour.  Early in the month, it appears in the southern sky near sunrise.  As the month progresses, it appears farther west.  By month’s end, it appears high in the southwest near sunrise.

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Saturn emerges from behind the sun and into the morning sky during the month.  It rises in the southeastern sky just before sunrise.  On December 19, it appears with the waning crescent moon as depicted in the chart above.

By month’s end, all five naked eye planets (Mercury, Venus, Earth, Mars, Jupiter, and Saturn) are visible during the night.  Bundle up, get outside the see Venus emerge from the sun’s glare in the evening sky and see Saturn emerge from the sun’s glare in the morning sky.

November 2104 Sky Watching

Welcome to November!  The length of daylight continues to diminish during November.  The northern mid-latitudes lose nearly an hour of daylight during the month.

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The blue area on the chart above indicates the length of daylight during November.  (Click the image to see it larger.)  With the switch back to standard time for most of the United States, the inevitable conversation occurs about daylight time and standard time.  A year ago. there was a discussion about changing to two time zones in the United States.  See commentary here.

NASA Photo

NASA Photo

Phase Date/Time Moonrise Moonset
Full Moon 11/06/14 (4:23 p.m.) 4:47 p.m. 7:06 a.m. (11/07)
Las Quarter 11/14/14 (9:15 a.m.) 11:46 p.m. 12:58 p.m. (11/15)
New Moon 11/22/14 (6:32 a.m.) 6:44 a.m. 4:56 p.m.
First Quarter 11/29/14 (4:06 a.m.) 12:21 p.m. 12:22 a.m. (11/30)
Times are Central Standard Time for Chicago, Illinois, from US Naval Observatory calculations. (For mjb)

Evening Sky

Mars is the only planet visible in the early evening sky  during the month.

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It is in front of the stars of Sagittarius low in the southwestern sky.  It sets about 3 hours after sunset, although it appears near the southwest horizon during early evening.

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Late in the month, the crescent moon moves past Mars.  On the evening of November 25, the moon is about 8 degrees to the right of Mars.  On the next evening.  the moon stands about 9.5 degrees above the Mars.

Jupiter

During November Jupiter moves into the evening sky.  Early in November it rises in the east-northeast around midnight.  It is well up in the southeastern sky at sunrise.

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It appears about 9.5 degrees to the upper right of Regulus.  Jupiter is now the brightest starlike object in the sky, until Venus reappears in the evening sky at month’s end.  It is slightly brighter than Sirius, the brightest star, that  appears low in the south during November mornings.

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Near mid-month, the moon moves through the region; on November 14, the last quarter moon appears near Jupiter and Regulus.  While the chart above shows the trio at 5 a.m., the moon rises just before midnight and can be seen in the eastern sky from moonrise until the sky brightens.  During the daytime with a very clear sky, Jupiter may be visible through binoculars by using the moon as  guide to fine it.

Mercury

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Mercury is the headliner in the morning sky.  It is at its best morning appearance of the year in the eastern morning sky.  The planet always appears near the sun.   During autumn, the solar system’s plane makes a very sharp angle with the horizon.  If Mercury is near its greatest separation with the sun, it appears a little higher in the sky.  The chart above includes a sketch of Mercury’s orbit (in red) showing the planet at the greatest separation it can have from the sun.  On the chart above, the star Spica appears about 4.5 degrees to the lower right of Mercury and will help identify it.  Locate a viewing spot with a  clear horizon.

Venus and Saturn

Venus and Saturn  are not visible this month.  Venus passed superior conjunction late last month and is moving into the evening sky, appearing low in the southwest around month’s end.  See our forecast for the appearance of Venus in the evening sky.  Saturn moves behind the sun (conjunction) on November and reappears in the morning sky later in December.

November provides a few planets for observing.  The view of Mercury early in the month is this year’s best opportunity to see the planet in the morning sky.  Jupiter rise high across the sky with a bright star nearby and the moon appearing with the planet at midmonth.  With more night hours in November sky watching awaits!

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