1. Highlighting the Near and Deep Sky
What’s Up E W
Highlighting the Near and Deep Sky
January , 2018 S

2. General Information January 2018
Among this month’s celestial happenings:
Earth cozies up to the Sun.
One of the major annual meteor showers peaks.
The Moon giveth and the Moon taketh away!
Sunset Range: 5:13 p.m. (January 1st) to 5:43 p.m. (January 31st).
End of Astronomical Twilight*: 6:47 p.m. (January 1st) to 7:13 p.m. (January 31st).
* This is “full darkness” – the sun has reached 18° below the horizon. It’s usually dark enough for observing about a half hour before this.

3. Moon Phases January 2018 Mon., 1st – Full Moon
Mon., 8th – Last Quarter (Fri./Sat. observing opportunities January 5th/6th)
Tues., 16th – New Moon (Fri./Sat. observing opportunities January 12th/13th)
Wed., 24th – First Quarter
Wed., 31st – Full Moon
Roughly speaking:
First Quarter Moon is highest at sunset and sets at midnight
Full Moon rises at sunset and is in the sky all night
Last (“Third”) Quarter Moon rises at midnight and is highest at dawn
New Moon sets at sunset and is absent from the sky all night

4. Celestial Events January 2018
Mon., 1st – “Supermoon” Full Moon occurs at same time as perigee; Moon distance Earth-radii. Closest perigee for 2018 (221,559 mi. vs. 238,900 mi. average).
Wed., 3rd – Earth at perihelion, AU from the Sun.
Wed., 3rd/4th – Quadrantid meteor shower. Best after midnight, but the just-past-full Moon’s light hides all but the brightest meteors.
Sat., 6th, 6:50 AM – Jupiter and Mars < 1/3º apart 45 min. before sunrise.
Sun., 14th – Thin crescent Moon (5.8% illum.) at apogee at 6:30 a.m. (about an hour before sunrise); distance Earth-radii (14.0% more distant than on the 1st). Jupiter, Mars, Saturn and Mercury also in view.
Wed., 31st – “Blue Moon” Total Lunar eclipse. Favors western U.S. For us, Moon sets at sunrise (7:24 AM), having entered umbra about 6:48 AM.

5. (~30 min. before full darkness)
January 15th, 7:30 p.m.
(~30 min. before full darkness)
For tonight, Dec. 18th, 6:10 p.m. is about 30 min. before full dark-ness.
Ceres
Pallas E W
3.25º - 13 days
Uranus
Neptune
Schmidt, et al., 2009, Science; with permission.
NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Pallas S

6. What’s Up programs are posted on the RVAS Website!
Find them under “Tips and Topics” or at:
Questions
???