2017: January Skywatching


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More articles about the planets and their current visibilities in 2017:


Happy New Year!  The length of daylight increases this month by 48 minutes.  On New Years Day, the Chicago area has 9 hours, 13 minutes of daylight with the sun rising at 7:18 a.m. CST and setting at 4:31 p.m.  By month’s end the sun sets at 5:05 p.m.  Notice either the sunrise or sunset point during the month.  It gradually moves northward along the horizon.


NASA Photo
NASA Photo
Phase Date/Time Moonrise Moonset
First Quarter 01/05/17 (1:47 p.m.) 11:38 a.m. 12:31 a.m. (01/06)
Full Moon 01/12/17 (5:34 a.m.) 4:15 p.m. 7:08 a.m. (01/12)
Last Quarter 01/19/17 (4:13 p.m.) 10:41 p.m. (01/18) 11:17 a.m.(01/19)
New Moon 01/27/17 (6:07 p.m.) 6:42 a.m. 4:58 p.m.
Times are Central Standard Time for Chicago, Illinois, from US Naval Observatory calculations.
(For mjb & afb)

Evening Planets

Brilliant Venus and the Red Planet Mars shine from the western sky during early evening hours.  Venus is nearly 100 times brighter than Mars.

Venus sets nearly 4 hours after sunset and Mars follows about an hour later.  Venus and the Moon are 4 degrees apart with Mars about 12 degrees to the upper left of Venus.   Look for the moon near this planetary pair during the first 3 days of January. During January, Venus and Mars appear to move closer together as the setting lines of the two planets begin to converge.

On January 12, Venus reaches is greatest angular separation from the sun (47 degrees) and sets 4 hours after the sun.

Venus continues to brighten throughout the month.  The clear, cold nights in the mid-northern latitudes seem to accentuate Venus’ brightness.  Its brightness increases about 30% during the month as it approaches its great brilliancy.  See this article for more about Venus and Mars  in 2017.

Morning Sky

Jupiter shines brightly from the southern sky in the predawn hours of the New Year near the star Spica.  As the month begins they are 4 degrees apart.

On January 20, Jupiter passes 3.5 degrees from Spica in its first of 3 passes (conjunctions) this year — a triple conjunction with the star.  See this article for more about Jupiter and Spica.  On the evening before this conjunction, the moon is about 3 degrees from Jupiter.

Mercury makes its best morning appearance of the year when it reaches its greatest angular separation (24 degrees) from the sun on January 19.  This planet is very elusive as it emerges from the sun’s glare to appear just before sunrise for several days.  Then it disappears back into the sun’s glare to reappear in the evening sky.  In this appearance it rises just before twilight begins, about 100 minutes before sunrise.  It appears higher in the southeastern sky sunrise approaches, but the sky is brighter.  The trick is to locate it when it is high enough to view with sky moderately dark.  This requires finding a clear horizon.

It helps if the moon or another bright planet is nearby.  On January 25, the moon appears about 6 degrees to the upper right of Mercury.  In binoculars, locate the moon,  Slightly move the binocular so that the moon appears to the upper right of the view.  Mercury appears at the lower left.

Saturn begins its appearance after its solar conjunction last month.  On January 1, Saturn rises about 90 minutes before sunrise and appears low in the southeastern sky,  It appears about 15 degrees from the star Antares.  On January 24, the moon appears 3 degrees from Saturn.

As with a new year, five planets are visible during a single night:  Venus and Mars in the evening with Jupiter, Saturn and Mercury in the morning sky.  Have a prosperous New Year!

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