Yukon Sky Report – September 2024
By: Shale Davis

The Moon

The Moon has long captured the imagination of our species, and for good reason. Even when viewed with just a pair of human eyes the view is truly spectacular. At times it takes the form of a narrow crescent, closely trailing the sun, while at other points it is bright enough to light up the landscape. This month the Moon will be easily visible to Yukoners making arcs over the southern horizon. On the 17th several events will happen simultaneously. For one it will reach a state colloquially known as Super Moon, which is a full moon that happens while it is at the closest part of its orbit to Earth. During a Super Moon it will appear about 14% brighter than during the reverse event, called a Micro Moon. Also on the 17th, the Moon will appear to approach very close to the planet Saturn, making it possible to view both at once with moderately wide-field optics.

The Planets

Mars- The famed Red Planet is gradually making its return to the spotlight. It can now be found at the feet of Gemini and is growing in brightness with each passing day.

Jupiter- Consisting of two and a half times as much mass as all the other planets combined, Jupiter is the undisputed king of the planets. Though it is still about two months away from opposition Jupiter is already dazzlingly bright. Also be sure to observe its 4 moons that are also visible.

Saturn- Having very recently passed opposition Saturn is at its prime. It can currently be found to the south, and is at its highest at about 1:00 Am. This season, its rings appear very edge on making for a unique view.

T Coronae Borealis Nova

Tucked away in the Corona Borealis constellation lies a seemingly inconspicuous star not even visible to the unaided eye. This is T Coronae Borealis, and it is in fact two stars (though they appear as only one) orbiting each other in violent dance. The larger component of the binary system is a massive red giant near the end of its life. The smaller member is an incredibly dense white dwarf (a stellar ember composed of electron degenerate matter). This White dwarf is gravitational stealing matter directly from the surface of its giant neighbour, creating an accretion (a ring of material orbiting its host). During outbursts the rate of transfer between the two stars increases dramatically, thus increasing the luminosity of the system. The last such outburst was in 1946 in which it temporarily brightened to magnitude +3, easily visible to the unaided eye. Another such outburst is anticipated sometime in the next few months.

Deep Sky Spotlight, Andromeda Galaxy

One of the most conspicuous objects in the night sky, the Andromeda galaxy, named for the constellation in which it resides, is visible overhead throughout the fall months. Due to the collective light of over a trillion stars, it is bright enough to be visible with only the unaided eye. If using a telescope, it is possible to observe the small satellite galaxies that orbit Andromeda. Regardless of your observation method, the photons your eyes absorb have been traveling through space for 2.5 million years.

The Andromeda Galaxy.

Clear Skies!