This year’s Geminid meteor shower will shoot across the sky from Dec. 4 to 17, peaking at 120 meteors per hour on morning of Dec. 14. With just a thin crescent moon for company, you will have no trouble spotting these falling stars, even after moonrise. Look at the night sky between Orion and Ursa Major, where the meteors appear to originate from the constellation of Gemini the Twins.
Slower than any other meteor shower, the Geminids move at a mere 35 kilometres per second, making them easier to spot and photograph. The best time to see them is from midnight to 4 a.m. but you should see plenty outside those times. If you decide to bundle up with a hot drink for an all-nighter on the night of Dec. 13, by early morning you will watch the moon rise with Jupiter, not a bad end to the night.
The Dec. 3 full moon will be the largest full moon of 2017, so expect the term “Supermoon” to crop up in the media. For those of you who prefer exact details, the moon will be at its closest to Earth (known as perigee) around 4 a.m. the next morning when it is 357,492 km away — that coincidence of being closest and fully lit is what makes a supermoon. The reason that we even get them and their opposite, the “minimoon” is that the moon’s orbit varies by over 50,000 km, from as close as 356,500 km (perigee) to as far as 406,700 km (apogee). This translates to a seven per cent difference in the apparent size of the moon — a difference that unfortunately, is impossible to see with the naked eye. It is far better to use ocean tides as a measurement, as they are highest after the supermoon.
Mercury and Saturn lie close together low in the southwest after dusk at the beginning of December and will sink rapidly during the month. Mercury will slip behind the Sun on Dec. 12 and Saturn will follow on Dec. 21. Saturn will return in January, while Mercury will reappear in the southeast before dawn in late December. Mercury will climb higher in the sky after its reappearance and will glow a bit brighter. You can find it at the end of December in the constellation of Scorpius the Scorpion.
Neptune can be found due south at sunset in the constellation of Aquarius the Water-bearer. Unfortunately, you will need either binoculars or a telescope to see the pale blue-gray disc. Catch Neptune as soon as the sky grows dark, since it will set around midnight at the beginning of December and by 10 p.m. at month’s end.
Uranus can be found one constellation east in Pisces the Fish. Although slightly brighter than Neptune, you will want binoculars or a telescope to properly identify Uranus by seeing its blue-green disc. It sets in the early morning hours, shortly before 3 a.m.
Mars appears low in the east shortly after 3 a.m. on Dec. 1, rising in the constellation of Virgo the Maiden. It will be next to a bright blue-white star called Spica and will shine half as bright. You can spot the planet because of its rusty colour. Mars will move southeast as the month progresses, eventually rising from that part of the sky on Dec. 31. It will drop out of Virgo as the month passes and fall into Libra the Scales. A crescent moon will appear slightly above the red planet on Dec. 13, with Jupiter double the distance below it.
Jupiter rises about 80 minutes after Mars in the southeast on Dec. 1, and as the nights progress it will linger in the constellation of Libra the Scales, waiting for Mars to descend to its level. Jupiter will be the more attractive of the pair for telescope viewing as you should be able to see plenty of detail and several moons. In contrast, Mars is just a bland disc. Jupiter will lie just beneath a thin crescent moon on Dec. 14.
Venus lies close to the southeastern horizon about 30 minutes before sunrise on Dec. 1 and is easy to see as it is the brightest object in the sky until the sun rises. This planet will sink closer to the horizon as the month moves on, making to harder to see when you have mountains around.
For those with telescopes four inches or larger, you can continue to observe Comet PANSTARRS (C/2016 R2) as it moves away from Orion’s Belt towards his shield (or bow, as I think of it; he is a hunter after all). To find it just draw an imaginary line through the stars making his belt and continue it towards his shield. C/2016 R2 will travel along that line away from Orion toward Taurus the Bull. This comet never comes close enough to the sun for naked eye or binocular observers, but it does have a very small debris tail that is mostly obscured by the head of the comet. Happy hunting with your telescopes on this one.
For those of you who having difficulty shopping for astronomy-minded friends and family this holiday season I can make a couple recommendations.
A pocket Naturalist Guide: The Night Sky is a glow-in-the dark guide to prominent stars and constellations north of the equator. It is easy to use and good for beginners and experienced astronomers.
SkyNews magazine is the Canadian magazine of astronomy and stargazing. Published bi-monthly, it is one of the sources I use for writing my articles. You can visit www.skynews.ca to order a subscription for someone.
Astronomy is the world’s best-selling astronomy magazine and another one of my favourite sources. It is published in the U.S., so you do have to deal with our fluctuating exchange rate. It is published monthly and you can get someone a subscription at www.Astronomy.com.
Finally, there is the Royal Astronomical Society of Canada’s Observer’s Handbook 2018, which has all the information you need for observing in 2018. It is the third source for my articles and can get a bit technical at times, but it has lots of good information. This is probably the easiest item to find as it is available at most major bookstores. I personally ordered mine from ChaptersIndigo as orders over $35 have free shipping anywhere in Canada and I am incapable of buying less than $35 in books.
Finally, a piece of advice. If someone has expressed an interest in astronomy, don’t immediately buy an expensive telescope as more often than not, it ends up sitting in the attic collecting dust. Start off with items to aid in the identification of celestial objects. If, after a while, the person is still interested, get them some binoculars. They don’t have to be fancy or expensive, they just have to be functional. If the person continues to show interest (or asks for one) feel free to buy a telescope, though I recommend that the person try out assorted telescopes to find one that is comfortable and easy for them to use. I use the time scale of Christmas-Birthday-Christmas for figuring out when to give the proper gift, though Birthday-Christmas-Birthday also works. But it is ultimately your choice as you know the person best.
Have a Merry Christmas and a Happy New Year.