October skies
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A meteor streaks above the constellatoin orion in 2019 - the green dot above the meteor is comet 46pwirtanen. - john mcphee
As the days get shorter and colder, the night sky offers a refuge of things bright and beautiful. And in October, we get a few bonuses as the seasons turn - at least for stargazers willing to lose a little sleep.
After midnight, the glittering constellations of Orion the Hunter and Gemini are rising in the east, while the Summer Triangle of the stars Altair, Deneb and Vega are hanging on for dear life in the west.
The cusp of the seasons is a good time to compare the brightness of stars that make up the constellations.
Orion's appearance is always a mixed blessing - if the Hunter is coming up, the temperatures are going down. But on the bright side, excuse the pun, this is an extraordinary group of stars.
Cygnus
- Wikipedia Commons
That's obvious when you turn from Orion to look overhead or to the west in late-night October. Most constellations have only one or two bright stars: you usually have to work to connect the dots with the dimmer remainder.
I can remember risking a neck strain trying to make out the six stars of the Northern Cross, officially known as Cygnus the Swan. This constellation straddles the Milky Way with its brightest, or alpha, star Deneb at the top of the cross.
Cygnus is now a familiar sight after years of exploring its treasures, such as the gold and blue double-star Albireo at the foot of the cross.
Then there's Orion, which stands out mainly because of his three-star belt. In a small telescope, the Orion Nebula below the belt is a facinating sight - just don’t expect to see the spectacular colours that make this such a coveted photographic object.
The Summer Triangle of Altair, Deneb and Vega (from bottom clockwise) hangs on for dear life in the west as winter approaches. - john mcphee
The brightness, or magnitude, of many of Orion’s stars are in the 0 to 2 range. That might not sound all that impressive. But under the magnitude system - which was created 2,000 years ago by the Greek astronomer Hipparchus and tuned up by the English astronomer Norman Pogson in the 1800s - the lower the number, the brighter the star.
In fact, really bright objects such as Venus, the full Moon and, of course, the Sun, go into the negative at -4, -13 and -26 magnitudes respectively.
Bears and queens
The other constellation that stands out as we scan the late-night October sky is Ursa Major or Great Bear, which prowls the northern regions.
Ursa Major boasts a number of second- and third-magnitude stars, which come together in the famous Big Dipper group.
So for the dedicated night owls out there, it's a rewarding time of year.
Double Cluster
The Double Cluster (also known as Caldwell 14) consists of the open clusters NGC 869 and NGC 884. - Wikipedia Commons
But there's lots to see at a more civilized hour. For example, the royal couple of autumn holds court in the northeast. Queen Cassiopeia (cass-ee-oh-PEE-uh) and the king Cepheus (SEE-fee-us) reign in the eastern wing of the Milky Way, which is studded with star clusters.
The big draw in this region is the Double Cluster, which technically is in the constellation Perseus. However, I find that two stars in Cassiopeia act as a handy pointer to this beautiful pair of star clusters, located about 7,500 light-years away from Earth.
In dark skies with the naked eye, the Double Cluster looks like a couple of dim, fuzzy stars. But through binoculars (see below), the clusters break down into glittering splashes of stars that easily fit into one binocular field.
the w-shape of cassiopeia is seen between the clouds in nova scotia. - john mcphee
To find them, locate the slanted W of Cassiopeia. The central star in the W and the dimmer star below and to the left point toward Perseus. The Double Cluster lies in this direction about halfway to Perseus.
Another nearby cluster, called M52, boasts more than 100 stars. It can be found between Cassiopeia (its top two stars point toward the cluster) and the house-shaped and relatively dim constellation of Cepheus.
Turning to the south, the skies in this direction look pretty desolate in late-evening October, after Sagittarius and Scorpius dip below the horizon. Shining a little light into the gloom is the first-magnitude star Fomalhaut (FO-mal-owt) which reaches its highest point in the south this month. At a distance of 22 light-years, it's one of our closer neighbours in space.
If you like stuff that moves, two meteor showers can be enjoyed in October and November. The Orionids and Northern Taurids aren't usually very active showers, producing about 10 to 25 meteors an hour. But both have been known to feature bright meteors and even fireballs.
Two eyes better than one
Back to those binoculars.
You often read in astronomy that the best telescope is the one you'll use the most. (if you’re in the market, here’s a great primer on buying your first one.)
A big scope is great for sucking up those photons from space, revealing distant galaxies and dim nebulae. But don't forget the time and effort it takes to set up this optical beast and drag it out to the backyard. I have two scopes - a 90mm refractor and an 8-inch Dobsonian. They're not monsters by any means but the Dob in particular takes a little muscle to move around.
Size does indeed matter and sometimes smaller is better, certainly when you're talking about portability.
So it's no surprise the optical equipment I use most often is my trusty set of 10 by 50 Carton Adlerblick binoculars. There's no setup time (except for occasionally mounting them on a tripod) and you might be surprised how many objects are within the grasp of those little twin barrels, particularly away from light polluted skies.
The pleiades star cluster is a lovely binocular object. this photo - taken on feb. 4, 2019 - includes the comet 46p/wirtanen, which shows up as a green spot at bottom centre. - john mcphee
If you have binoculars already, give them a try on the Moon and bright star clusters like the Pleiades. The Moon in particular offers a wealth of detail for binocular users. Try observing when the Moon is at first quarter or last quarter phases, when craters are highlighted by the shadow of the terminator, the line that separates the sunlit part of the lunar surface and the darker portion.
You can see a lot during the full Moon as well. Craters such as Tycho and Copernicus have ray systems that are spectacular in binoculars. The rays result from the spray of molten material ejected from the meteor impacts that created the craters.
run away from the monsters
If you're looking to buy a first pair of binoculars, choose ones that will be useful for astronomy, as well as terrestrial observing such as birdwatching. You’ll want a pair with a magnfication of 7 to 10 in order to glean the most detail out of star clusters and lunar craters.
The suggesetions in the review I linked to above include monster sizes such as 25 by 100, which must be mounted on a tripod. These are not recommended for first-time buyers - while they can provide amazingly wide and bright views, they’re cumbersome and usually much more expensive.
Astro nuts
A group of astronomy enthusiasts (including me in middle) talk shop in St. Croix, Nova Scotia. - Halifax RASC
But do buy binoculars that have a tripod adapter socket. It’s amazing how simply steadying your equipment will improve your viewing experience. (That “steadier the better” motto also applies to telescopes - a poor tripod will render even a good scope useless.)
You may not get a tripod right away but after you become comfortable observing with binoculars, it’s a helpful next step. You’ll also need a 1.25-inch adapter to connect your binoculars to the tripod.
I find it gets uncomfortable to hold even my 10 by 50 binoculars for any length of time, so for extended observing I plunk myself in a deck chair in mild weather to steady my arms or mount them on a tripod.
