starry night above campfire

Eyes on the skies — June, 2017

Welcome to the Ontario Parks “Eyes on the Skies” series. This space (<– see what we did there?) 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.

June formally ushers in summer, that time of the year when Canadians leave the confines of their homes and make their way to the wilderness. And stargazing is a uniquely memorable part of our experience.

Perhaps that’s because so many Ontarians live in areas with light pollution. Citydwellers seldom see the stars and then, only the brightest ones. But to miss the stars is to lose our connection with the beauty and mysteries of the skies.

Heading outside? Here are our astronomical highlights for June, 2017:

The sun

The sun reaches Solstice on June 21 this year (see the March edition for more about solstices and equinoxes). On this day, the sun will have reached its highest point in the sky as viewed from North America. It is also the longest day (in terms of the amount of sunlight).

In Canada, June 21 is also National Aboriginal Day, in recognition and celebration of the unique heritage, diverse cultures and outstanding contributions of First Nations, Inuit and Metis peoples in Canada.

Long June days also provide us with the opportunity to enjoy spectacular sunsets.

Why do some sunsets appear red?

The answer has nothing to do with the sun, but everything to do with the sky and our atmosphere.

sunset over lake

Our atmosphere, as clear as it looks, is actually made up of trillions and trillions of grains of dust, pollen, droplets of water and ice crystals. These items can actually change the way light behaves. Molecules of water and ice act like prisms, bending and scattering a beam of white light into different colours.

Most of the water and ice particles scatter (deflect) the blue light from the sun, leaving more of the yellow light behind. When the sun is near the horizon – either at sunrise or sunset — the light that comes to our eyes must travel through more atmosphere than when the sun is directly overhead.

diagram of different vantages for looking at sun

As a result of the atmospheric scattering of the blue light, and the sun and surrounding sky often take on a reddish colour that is beautiful to behold (though we should never stare directly at the sun).

The moon

lunar phases

June’s phases of the moon occur as follows:

  • First quarter on June 1
  • Waxing gibbous on June 5
  • Full moon on June 9
  • Waning gibbous on June 13
  • Last quarter on June 17
  • Waning crescent on June 20
  • New moon on June 24
  • Waxing crescent on June 28

The planets

jupiterThere are two planets, prominently on display this summer. Jupiter (discussed in our May edition) is well up in the constellation of Virgo, near Spica, at sunset.

Saturn (to be discussed in our July edition) can be found low in the south, near the border of Ophiuchus, Scorpius and Sagittarius, around midnight.

Featured constellations: heroes and serpents

In this month’s edition of Eyes on the Skies, we will discuss the constellations of Hercules, Ophiuchus and Serpens.

constellations: Hercules, Corona Borealis, Ophischus, Serpens Caput, Serpens Cauda

Ophiuchus

Those within the medical discipline are very familiar with the symbol that has come to represent their craft; a staff surrounded by two serpents coiling up its length. This symbol — the caduceus — reminds us of the ancient Greek legend for the origin of modern day medicine.

A long time ago Asclepius, son of Apollo, met up with a serpent which he severely injured by beating it with his staff. Another serpent brought herbs and laid them atop the injured one, whereupon the injured serpent seemed to gather its strength and slithered off into the bushes with its friend. From this encounter, Asclepius was said to have learned the medicinal arts.

The constellation of Ophiuchus, the serpent bearer, represents the healer Asclepius. But shouldn’t he have a serpent nearby? As a matter of fact, he does…

Serpens

Near Ophiuchus (actually running through it) lies the constellation of Serpens. Serpens has three main parts: Serpens Caput represents the head, Serpens Cauda represents the tail, and the body lies within Ophiuchus itself.

Just below Serpens Caput is the globular star cluster M5. We’ll talk more about globular clusters below, in the section on M13.

Above both Ophiuchus and Serpens lies the famous hero of ancient Greco-Roman lore: Hercules (or Heracles in Greek).

constellations: Hercules, Corona Borealis, Ophischus, Serpens Caput, Serpens Cauda

Hercules

For all of his impressive tasks and great power, the constellation of Hercules is actually one of the smaller ones in the sky, but the constellation is ancient even by Greek standards.

Two Greeks living almost 2,500 years ago, Eudoxus and Aratus, are largely responsible for the ancient Greeks learning about the far more ancient Sumerian/Babylonian constellations (these date back to between 3,000 to 4,000 years ago).

In the Classical tradition, Hercules was the son of Zeus. Zeus’ wife Hera disliked Hercules, who tried to make his mortal life difficult. To try to atone for his sins, Hercules undertook 12 “impossible” tasks (labours). During this time, the Oracle of Delphi renamed Hercules to Heracles, which means “glory of Hera.”

Four brighter stars make up a parallelogram known as “the keystone of Hercules.”

stars

Towards the top right (about 1/3 of the way down from the top-right star) is a beautiful object known as M13. M13 is the 13th object in a catalogue of interesting objects in the sky. M13 is known as a Globular Star Cluster, a cluster made up of hundreds of thousands of stars about 22,000 light years away.

Corona Borealis – the Northern Crown

Just to the west of Hercules is a lovely u-shaped pattern of stars known as the Corona Borealis or “Northern Crown.” This distinctive pattern of stars was said to be the crown that Dionysus gave the Cretan princes Ariadne for their wedding. After the wedding, Dionysus tossed it into the sky where the jewels shine today as stars.

This completes our review of the June skies

Come back next month to learn about the Milky Way, the Summer Triangle and the planet Saturn!