Skywatching January 2014


Sun

Date Sunrise Sunset Daylight
January 1 7:18 a.m. 4:31 p.m. 9 hours, 13 minutes
January 15 7:16 a.m. 4:45 p.m. 9 hours, 29 minutes
January 31 7:04 a.m. 5:05 p.m. 10 hours, 1 minute

Times are Central Standard Time for Chicago, Illinois, from US Naval Observatory calculations.

Earth and Sun are closest (perihelion) on January 4.  The separation is about 91.4 million miles.

Moon Phases

Phase

Date

Moonrise

Moonset

New Moon

January 1

7:07 a.m.

5:17 p.m.

First Quarter

January 7

11:00 a.m.

12:20 a.m. (01/08)

Full Moon

January 15

4:43 p.m.

7:08 a.m. (01/16)

Last Quarter

January 24

12:35 a.m.

11:15 a.m.

New Moon

January 30

6:30 a.m.

5:16 p.m.

Times are Central Standard Time for Chicago, Illinois, from US Naval Observatory calculations. (For mjb)

Evening Sky

Venus

Venus rapidly exits the evening sky early in the month, passing between Earth and the sun (inferior conjunction) on January 11, reappearing in the morning sky late in the month.

venus_lune_130102

Just nine days before Venus reaches inferior conjunction it appears with a thin crescent moon in the southwestern sky.  The diagram above shows the pair at 5 p.m. CST as seen from the Chicago area.  For other locations look about 30 minutes after sunset.

Jupiter

After Venus leaves the evening sky, Jupiter is the brightest starlike object among a section of the sky full of bright stars.  Jupiter reaches opposition on January 5.  It rises at sunset, appears in the south at midnight and sets at sunrise.  It is on the opposite side of the sky from the sun.  This occurs when our planet passes between the sun and a planet that orbits the sun farther away from the sun than Earth.

As as the distant worlds revolve around the sun, they appear to move eastward compared to the starry background.  Yes, they rise in the east and set in the west each day as our planet rotates.  Their orbital motions carry them eastward.  When the outer planets are at opposition, they appear to stop their eastward movements and reverse their courses, moving westward (retrograde) for a period of time.  They then appear to stop retrograding, moving eastward again.  This apparent westward motion is an optical illusion from our planet passing these distant worlds.

jupiter_1401-31

During January, Jupiter retrogrades in front of the stars of Gemini, easily found by its two brightest stars Castor and Pollux.  The chart above shows Jupiter’s January retrograde motion.  The numbers indicate Jupiter’s positions on the January dates (1, 11, 21,31).  Delta Geminorum (The fourth brightest star in the constellation Gemini.  Star brightness in a constellation is designated with a Greek letter.  Delta is the fourth letter of the Greek alphabet.) serves as an excellent milepost for planetary movement.  During the month, notice the position of Jupiter compared to Delta.

jup_lune_140114

On the evening of January 14 , the nearly full moon appears near Jupiter.

Mercury

Elusive Mercury appears in the evening sky during the second half of the month.

lune_merc_140131

Just 26 hours past the new phase and with about 1% of the moon illuminated, the moon appears near Mercury on January 31.  The pair is about 5 degrees apart.  Find a clear horizon and begin looking about 30 minutes past sunset.  Binoculars should help you find the planet and the moon in bright twilight.

Morning Sky

The New Year begins with three planets in the morning sky:  Jupiter, Saturn, and Mars.

Jupiter

With Jupiter at opposition as described above, it is visible all night appearing near the western horizon before twilight begins.

jupiter_lune_140115

On the morning of January 15, the nearly full moon appears near Jupiter on the western horizon at 5 a.m.  This is a continuation of the evening view of Jupiter for January 14 described above.

Mars and Saturn

Mars and Saturn are in the morning sky throughout the month.  They can be found in the southeastern sky.  While they are not as bright as Jupiter and Venus, they are easy to spot.  Mars races toward and passes Spica during the month.  Saturn is nearly between Zubenelgenubi and Zubeneschamali.

sat_mars_1401

The planets can be distinguished from the stars because they move compared to the distant starry background as they revolve around the sun.  They appear to move eastward compared to the sidereal tapestry.  The chart above shows the eastward motion of the planets during January 2014.  The green dots show the planetary positions on those January dates (1, 11, 21, 31).  The green lines indicate the overall motion.  Mars moves over 11 degrees eastward during the month while Saturn only moves about 2 degrees.  Mars’ orbital motion is over 15 times faster than Saturn’s.  On January 28, Mars passes about 5 degrees above Spica.

lune_mars_saturn_1401

The moon moves through the region in the morning sky beginning January 22.  Here are the events:

  • January 22:  Looking south at 5 a.m., the waning gibbous moon is 10 degrees to the right of Mars.
  • January 23:  The moon is less than one degree to the left of Spica.  (The image size of the moon is reduced on the diagram.  The size of the moon on our diagrams is normally oversized.)
  • January 24:  The moon is about midway between Mars and Saturn.  (Mars to Moon, 17 degrees; Saturn to Moon, 15 degrees.)
  • January 25.  The moon is about 2 degrees to the lower right of Saturn.

Venus

After its inferior conjunction on January 11, Venus rapidly moves into the morning in the eastern sky.  It is a “Morning Star” for most of 2014.

lune_venus_140128

Venus appears near a waning crescent moon on January 28.

Venus rapidly moves into the morning sky.  By the end of January, it rises two hours before sunrise.

For more about Venus as a morning star in 2014, read our detailed posting here.

Visible Solar System

planets_140115

This diagram shows the positions of the visible planets on January 15, 2014 as seen from north of the solar system.  Mercury and Jupiter are visible in the evening sky.  Notice that Jupiter is just past opposition by mid-month as it appears near the midnight line.  Both Venus and Mercury are in the same direction as the sun appearing in the sky, primarily during the daytime hours.  Saturn and Mars are in the morning sky.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: