GHOSTLY LIGHTS AND GAS GIANTS
As nights begin to lengthen in September, skywatchers are able to spend more time under the stars while temperatures are still pleasant. From ghostly celestial glows to neighbouring worlds, an amazing cosmic treasure trove awaits. Near moonless skies the first two weeks of September offers an amazing chance for keen-eyed skywatchers to catch a glimpse of the Zodiacal Lights. If you are willing to head out to the dark countryside, look for a pyramid-shaped glow — fainter than the Milky Way — rising above the eastern horizon before sunrise. Humans do not cause this eerie beam of light, but instead it is formed by sunlight reflecting off countless dust particles scattered across the solar system, between the planets.
Orbiting the sun are countless number of these dust grains which reflect and scatter sunlight in such a way that make them visible in our sky — much like we see household dust floating in front of a sunny window. Radiating out well beyond the orbit of the planet Mars, most of this space debris is continually generated from asteroid collisions and leftovers from comets as they have been rounding the sun for eons. So in observing the zodiacal light skywatchers are actually witnessing the ancient remains from the birth of our solar system over 4.5 billion years ago.
Known and sometimes feared since ancient times, zodiacal light was recorded by many ancient cultures. First century Romans likened it to glows of distant unseen fires scattered in the sky while even earlier the Greek philosopher Aristotle concluded that these misty patches of lights in the heavens were caused by far off volcanic eruptions.
Also putting on a sky show will be the gas giant planets posing with our moon. As night falls on Sept. 13, gaze towards the low southwestern sky for a setting crescent moon joined by the brilliant planet Jupiter. Both celestial objects will appear to set below the horizon by 10 p.m. local time. Then on Sept. 17 as dusk sets, the waxing gibbous moon appears perched above the golden-hued Saturn high above the southern sky. Keen eyed stargazers can spy below the pair of worlds the familiar looking pattern of stars known as the Teapot belonging to the constellation Sagittarius.
In the last few days of the month, dark, early night skies will offer great opportunities to check out the giant constellation Pegasus — the flying horse riding the northeast sky. The winged steed is the seventh largest constellation in the entire sky and is easy to track down thanks to four brilliant stars marking out a giant square.
A large piece of celestial real estate, this “Great Square of Pegasus” is large enough to contain more than 30 full moons side by side. Though each corner star is only moderately bright, they’re relatively easy to locate because there are no stars in this area of the sky that are as luminous.