October skies

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 (fow·muh·lowt) 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.

Like many star names, Fomalhaut derives from an Arabic phrase, in this case “mouth of the fish,” referring to its location in the constellation Piscis Austrinus.

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

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.

 



 



 

The Hunter ascendent

Canis Major and Orion are seen in the Annapolis valley. - John McPhee

Orion the Hunter has risen into view above the city skyline on a frosty late November night.

That’s no small feat given the light pollution that blights the sky above that cityscape. Even on the clearest and most transparent nights, all but the brightest stars are dimmed by the ever-expanding orange washout that comes with urbanization.

Luckily, the winter constellations such as Orion and Canis Major boast some of those stellar beacons.  

It’s particularly easy to track down the Hunter, mainly because of the diagonal trio of stars that make up his belt. (The photo above shows a dark sky view with Orion at upper right and Canis Major to the left). 

Alnitak, Alnilam and Mintaka (from bottom up) appear to line up neatly to hold up the Hunter’s pants. In fact, these stars are dozens and hundreds of light-years away from each other in space.

If you look above Orion in December's evening skies, two bright stars might catch your eye, one red and the other blazing yellow.

Let's begin with the brighter of the pair, the yellow star Capella. This is the brightest star nearest the northern celestial pole, so it's visible every night at some time in our latitude. Capella, the fifth-brightest star in the northern night sky, is quite similar to the sun, except for its huge size. It's the alpha star of the constellation Auriga (oh-RYE-guh), which contains some interesting sights for binocular and telescope observers.

Its main attractions are three open star clusters, M36, M37 and M38. It's rare to have so many bright clusters in one constellation, especially in the relatively sparse winter skies.

In summer, the Milky Way, particularly around Sagittarius, fairly bursts with open and globular clusters.

You don't have to look far from Auriga to find more clusters high in the December sky. That red star I mentioned would be Aldebaran (al-DEB-uh-ran), a supergiant that marks the spot for the huge open cluster, the Hyades (HY-uh-deez). Aldebaran is not actually part of the V-shaped cluster; it lies only 68 light-years from Earth, while the cluster is 150 light-years away.

The Hyades contains about 200 stars and it's a spectacular sight in binoculars, covering too much of the sky to be easily viewed in a telescope.

Comet 46pwirtanen (the green dot) is seen below the pleiades cluster on feb. 4, 2019. - john mcphee

Comet 46pwirtanen (the green dot) is seen below the pleiades cluster on feb. 4, 2019. - john mcphee

Another must-see for binocular observers is M45, also known as the Pleiades (PLEE-uh-deez). There's nothing else like it in northern skies. This open cluster is small enough to present a stunning sight when using low-power views in a telescope. But it's big enough to be easily visible to the naked eye; it's claimed that people with excellent eyesight can see six or even seven of the cluster's brightest stars. No problem seeing those stars with binoculars - the cluster fits easily in most binocular fields. Your neck will probably give out before you want to move on from this celestial jewel box.

You can put away your binoculars and still enjoy another highlight of the winter sky.  The constellation Perseus (PURR-see-us) rewards you with a glittering ladder of stars that climbs toward the zenith in mid-evening. Look just to the east of M45 to find this much larger celestial group. 

You can give your neck a rest and look low in the east to find the brightest planet in the evening sky this month, Jupiter. This largest of the planets (and second brightest after Venus) rises after 10:30 p.m. in November.

If you’re up with the birds, you’ll see the ringed planet  Saturn (but you’ll need a small telescope to see those rings). It rises just before the sun in the southeast in November and later as the winter really takes hold.