night sky

Eyes on the skies — September

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

Many people consider September to be the finest month of the year to enjoy Ontario’s outdoors.

The bugs have all but left and the daytime temperatures are cooler, making the weather ideal for strenuous activities such as hiking or canoeing. To top it off, the leaves begin their beautiful transition through the colours of fall.

With the much shorter days, the nighttime skies are full of celestial splendors that we hope you will enjoy discovering in this edition of “Eyes on the skies.”

Here are our astronomical highlights for September, 2019:

The sun

The sun continues its apparent drop in elevation and passes through the Celestial Equator on September 23 at 3:51 am. The Celestial Equator is an imaginary projection of the Earth’s Equator into space. So on this day, the sun stands directly above the equator and we have (roughly) equal amounts of daylight and night, or equinox.

There are two equinoxes in a year: one in the spring (usually around March 20) and one in the fall, around September 23.

Lake beside forest with leaves changing colours all under a blue sky with bright sun

If we didn’t have Daylight Savings Tme, the sun would rise roughly at 6:00 am and set at roughly 6:00 pm. However, as our clocks are currently forward by one hour, the sunrise and sunset times on the equinox are pushed up an hour to 7:00 am and 7:00 pm.

Check out our March edition to learn more about the Earth’s orbit around the sun.

Sunrise and sunset times

September 1 September 15 September 30
sunrise 6:46 am 7:03 am 7:22 am
midday 1:28 pm 1:21 pm 1:16 pm
sunset 8:04 pm 7:37 pm 7:08 pm

The moon

The moon has long captivated observers of all ages. Even a pair of small binoculars will reveal the craters of the moon.

Photo of a full moon.

September’s lunar phases of the moon occur as follows:

  • Waning crescent on September 3
  • First quarter on September 6
  • Waxing gibbous on September 10
  • Full moon on September 14
  • Waning gibbous on September 18
  • Last quarter moon on September 22
  • Waning crescent on September 25
  • New moon on September 28

Picture showing the visual depiction of each phase of the moon.

The planets

Jupiter and Saturn continue to be well placed in the south after sunset. Jupiter rises first and sets by 10:00 pm. Saturn is a little further towards the east, and sets around midnight.

Picture of the night sky with the Moon, Jupiter, and Saturn highlighted.
Wide field view of the Moon, Jupiter and Saturn on September 5. Image courtesy of SkySafari 6 Pro

On the night of September 5, Jupiter and the moon will appear to be relatively near each other, as seen from the Earth.

Picture of night sky with the Moon and Jupiter shown.
Binocular field of view showing the moon and Jupiter on September 5. Image courtesy of SkySafari 6 Pro

Meteor showers

September is traditionally a quieter month for meteors. While there are no meteor showers peaking (concentrated activity in which you may see many meteors that originated from the same source), there are always sporadic meteors visible in the dark skies of our provincial parks.

Night sky

Typically in September, between five and ten meteors can be seen, especially after midnight, remnants of powerfully strong meteor showers of which, today, we only see the echo of what may have been an incredible sight eons ago

Featured constellations

In August’s featured constellations, we discussed Sagittarius, Capricornus and Delphinus.

There is a water theme in September’s edition.

Diagram of September constellations.

We discuss Pegasus the flying horse (moose or baseball diamond), Aquarius the water bearer, and Piscis Austrinus the southern fish.

Did you know…

…the speeds of light and sound can provide us with a lot of useful information? That we can even apply when we’re camping? Read how we can apply this knowledge to stay safe when we’re camping in our post “Understanding the speeds of light and sound.”

This completes our review of the September skies. Come back next month to learn more about our galaxy and the stars of October.