December 2018

Apologies for the delay this month. Backstage passes to rocket launches apparently take up a lot of time. More to come on another episode about that...


Welcome to Observing With Webb, where a high school astronomy teacher tells you what you’re looking at, why it’s so cool, and what you should check out later this month…at night.  Don’t forget to check out my Podbean page, YouTube Channel, and Twitter feed, or get my podcast feed on Stitcher, or iTunes.

Geminid meteors, lunar close encounters, and even a conjunction all make December of 2018 a pretty active month, along with the longest nights of the year to give you plenty of time to get out there and see something stellar.


Naked-eye PLANETS...

  • Around Sunset – Saturn (SW-1st half), Mars (S)
  • Throughout the night – Mars (S-->W)
  • Morning – Venus (SE), Mercury (ESE-2nd half), Jupiter (SE-2nd half)



  • Should be able to catch it low in the ESE by the 8th and every morning after 6am for the rest of the month. Gets really close to Jupiter on the 21st. About 25˚ down and to the left of super bright Venus.


  • This is the highlight of every morning. As a crescent (in binoculars) in the beginning of the month, it is VERY bright, and easily visible about 30˚ above SE horizon all month. It rises as early as 4:00am. If you have binoculars or a telescope, you should easily see it transform from a crescent to a half phase throughout the month, about the size of Jupiter in your view.


  • Mars is already in the S around sunset, traveling toward the W and setting a little after 11pm each night. Moves from Aquarius to Pisces throughout the month. Absolutely gorgeous and bright and red right now, but not so breathtaking in a telescope. However, if you’re looking at it on the evening of the 6th, Neptune is right nearby (telescope needed).


  • Wait for the second half of the month, when Jupiter starts rising up out of the SE and catches up to Mercury on the 21st, passing it for the rest of the month.


  • Your last chance for a little while is the first two weeks in December. It’s only about 10˚ above the SW horizon, and sets less than an hour after sunset.



New Moon – 7th (darkest skies)

First Quarter Moon – 15th (Visible until midnight)

Full Moon – 22nd (Visible all night)

Last Quarter Moon – 29th (Visible from midnight into the morning)


3rdClose Encounter – Moon, Venus – Anytime between 3:40am and 7:08am sunrise, look SE to find a beautiful thin crescent Moon just 5˚ above the beacon that is Venus.

5thClose Encounter – Moon, Mercury – If you get out after 6:15am with a clear view of your SE horizon, an even thinner crescent Moon will be about 5˚ above Mercury, until dawn washes out the smallest planet.

6th – 7thClose Encounter – Mars, Neptune – You’ll absolutely need a telescope for this, but check out Neptune being less than 1˚ away from Mars. Use online star charts for specific directions, or just look for the blue-ish dot near red Mars in your scope.

8th Close EncounterMoon, Saturn – Find a VERY thin crescent Moon off in the SW after sunset and you’ll see Saturn only 4˚ up and to the left. Make sure you have a clear horizon.

13th, 14thGeminid Meteor Shower – A decent year for the Geminids, given the moon will be just shy of first-quarter (less than half-lit and setting after 11pm), giving us a shot at over 100 meteors per hour later in the night, depending on your light pollution levels.

Some advice for watching:

  • Find a dark location and lie down in a reclining chair or swimming pool floaty
  • Look at the whole sky, but note Gemini is where the radiant is - where the meteors will appear to be coming from. Gemini will be in the East after sunset, South after midnight, West in the morning.
  • Check the weather to see if the skies will be clear
  • Adapt your eyes to the dark by staying away from light sources or using a red light if you need to look at a star chart or not trip over something. 
  • If you’re feeling extra nerdy, do a scientific meteor count (S&T and IMO)
  • Or find out if your local astronomy club or museum is holding a viewing party.

14th Close EncounterMoon, Mars – An almost half-lit Moon will get to within 4˚ below Mars tonight.

21stConjunction – Jupiter, Mercury – Get out in the morning after 6:20am but before 7ish and look very low in the SE for Jupiter and Mercury side-by-side less than 1˚ apart. Mercury will be on the left and dimmer than Jupiter.

21stWinter Solstice - The longest night and shortest day of the year for the Northern Hemisphere. More info here:

31stMorning Lineup – Mercury, Jupiter, Venus, and the Moon will all be lined up and almost equidistant apart. Just get out there before dawn.



(see sky map link at the bottom for a Star Map for this month)   

After Dinner:

Pegasus & Andromeda - Look pretty much straight up you’ll be able to see the Great Square of Pegasus, with Andromeda curving off of one corner. If your skies are decently dark, you might catch the faint fuzz that is the Andromeda Galaxy.

Before Bed:

Taurus & the Pleiades – Look almost straight up, but down toward the South a little bit and you’ll find the lovely cluster of stars known as the Pleiades, the Seven Sisters, Subaru, or the mini-mini-dipper. You can easily see 5 or 6 of them with the unaided eye, and perhaps a 7th, depending on light pollution and your eyes.  To the left about 5˚ will be the V constellation of Taurus the bull, with bright red Aldebaran as its brightest, and one eye of the bull. Oh, and if you follow a line connecting these two to the left about 10˚, you’ll find Orion.

Before Work:

Leo – Look South, halfway up the sky, to find the backward question mark and right triangle that is Leo the Lion.

Use a sky map from to help you out.


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