Campfire at night in winter

Eyes on the skies — December, 2017

Welcome to the Ontario Parks “Eyes on the Skies” series. This will cover a wide range of astronomy topics with a focus on what can be seen from the pristine skies found in our provincial parks.

December brings some of the darkest skies of the year.

Take advantage of this great opportunity to go out into our parks. Breathe in the peace and solitude of December days and the bounty of the starlit skies.

Here are our astronomical highlights for December, 2017:

The sun

Sunrise

December 1 December 15 December 30
Sunrise 7:47 am 8:01 am 8:08 am
Midday 12:15 pm 12:21 pm 12:29 pm
Sunset 4:42 pm 4:41 pm 4:50 pm

The sun completes its apparent southerly drop on the winter solstice on December 21 at 11:28 a.m. To great celebration, it then begins its northerly rise.

See our post from March to learn more about the solstices and equinoxes.

The winter solstice and the Saturnalia

Night sky in winter

Ancients all over the world observed the daily drop of the sun, always concerned that perhaps one day the sun would not rise again.

In the May edition, we learned of the Greek legend of Demeter and Persephone. In this legend, the gods (Demeter, in particular) could affect the climate, creating six sunny “growing” months and six dark “barren” months.

Around the time of the winter solstice, the Romans celebrated a great festival known as the Saturnalia. This festival was named after Saturn, the Roman god of sowing or seed.

It ultimately became a seven-day festival of great magnitude. Many liberties were granted to all members of the Roman realm. People could do and say what they wanted, and slaves were even allowed to sit at their masters’ tables.

Towards the end of this festival, presents made of wax representing people or fruit were usually given to friends and family alike. A week later, the Romans celebrated their New Year with another celebration in which houses were decorated with greenery and lights and presents were given to children.1

If this reminds you of a holiday we all know and love, you are in great company. Many scholars believe the celebration of Christmas took place during the Saturnalia, as there was more freedom for the early Christians to celebrate without fear of persecution.

In time, a number of Saturnalian customs became interwoven with the customs and practices of Christmas we know today.

The moon and the planets

December sees the return of Jupiter and Saturn just before sunrise in the morning skies.

Stay tuned to watch a very close pairing between these two planets in January, 2018!

December’s lunar phases are as follows:

Phases of the moon

Featured constellations: Eridanus, Lepus and Monoceros

As we round out the year of constellations, we will focus on some of the fainter ones seen at this time of the year.

As they are faint, one must travel to pristine dark skies, such as those in provincial parks, to see them well.

Map of the constellations

 The River Eridanus

This constellation is of ancient origin, and has long represented a river.

Since it was brought to Greek knowledge through Aratus (who learned about it from the Egyptians), many people associate the Nile River with Eridanus.

This constellation is the sixth largest, and a good portion of it lies below the horizon from which we can observe it in the north.

Lepus the Hare

While Eridanus is one of the largest constellations, Lepus the Hare is one of the smallest.

Lying beneath Orion’s feet, the hare must surely have been a tease for the great dog to the east (Canis Major). The hare has long represented perseverance (it flourishes in all seasons) and fertility (it is highly prolific).

In Ontario, we have two native types of hare, the Snowshoe Hare and the Cottontail Hare, as well as one introduced hare, the European Hare.

 Monoceros the Unicorn

Most of the constellations described over the year originated in ancient times.

Monoceros the Unicorn was identified in the early 17th century. Being a faint constellation, it has no precursor in Greek mythology. However, the winter Milky Way runs through the constellation. It contains some interesting objects.

Red collection of stars and gas

Perhaps the most interesting is the very large molecular cloud known as the Rosetta Nebula. Young, hot, bright stars near the centre charge up the molecules of gas. They in turn emit radiation, some of which we see as red light.

December meteor showers

Most people are familiar with the annual Perseid meteor shower in August, but did you know about the almost equally enjoyable Geminid meteor shower in December?

This shower peaks on the night of December 13 and morning of December 14. It can provide viewers in dark skies with up to 120 meteors per hour. Interestingly, this shower is not associated with a comet but with an asteroid.

The best time to look is after 1:00 am, at which point the view of the night sky is starting to face in the same direction as the Earth’s travel around the sun.

For a good explanation of meteor showers, check out this link.

This completes our review of the December skies…

Come back next month to learn about the calendar.


1The Editors of Encyclopædia Britannica. “Saturnalia.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 20 July 2017, www.britannica.com/topic/Saturnalia-Roman-festival.