Two comets together in the pre- dawn sky

Astronomers around the world, both professional and amateur, are waiting with great anticipation to see if Comet ISON survives its journey around the sun later this month.

If it does survive its perihelion swing around the sun intact, hopes are that it will sport a magnificent tail and be bright enough to be seen even in broad daylight. However, it is a big “if,” as ISON is classified as a sungrazer, meaning that its perihelion pass by the sun will take it dangerously close to the sun’s surface, greatly increasing the chance that it will fragment into small pieces or disintegrate altogether.

It doesn’t help either that ISON is a virgin comet making its maiden voyage into our solar system. Such comets are notorious for failing to meet expectations in terms of brightness.

A good opportunity to see Comet ISON will come in the pre- dawn hours of Nov. 17- 18. Look to the southeast about one hour before sunrise. Mercury ( see upcoming information) will sit low above the eastern horizon, with Comet ISON to its upper right next to the star Spica in Virgo. Although Comet ISON is now within the range of binoculars and scopes under a dark sky, we will really have to wait until after perihelion on Nov. 28 to see if this comet, labelled as potentially being the “comet of the century,” lives up to the hype.

While waiting to see what Comet ISON will do, dedicated viewers will experience a rare event this month if they venture out in the pre- dawn hours to look for ISON. A second comet, Comet Encke, graces the pre- dawn sky, not all that far from ISON. At its best morning apparition in a decade, Comet Encke can be found low in the eastern sky about two hours before sunrise. Encke visits our inner solar system every 33 years. It passes close by the bright star Spica in the constellation of Virgo – the maiden on Nov. 11- 13. Observers using binoculars or a scope should see a fairly bright central core, with a narrow fan- tail extending westward. Both ISON and Encke are expected to brighten from magnitude 7 to 5 during the first half of November.

In the latter part of November, moonlight will interfere with the view of both comets and, by month’s end, they will both be lost in the increasing bright dawn as they draw nearer to the sun. For the latest updates and finder charts for both comets, Google their respective names or go to www. astronomy. com or www. skyandtelescope. com. If at all possible, don’t miss the opportunity to witness this rare event of two comets in the sky together.

Venus starts the month low in the southwest sky as darkness falls, but slowly climbs higher in the night sky as November progresses. Venus will brighten slightly this month, increasing from - 4.5 to - 4.8 magnitude ( remember, negative numbers denote greater brightness).

Jupiter, shining at - 2.5 mag., makes an appearance around the middle of November, rising in the east around 10 p. m. By about 11 p. m. it should be high enough in the night sky for good viewing, and will be at its best for observing when it is almost directly overhead in the pre- dawn hours. Earth is about 10 per cent closer to Jupiter in November than at other times, so Jupiter will appear slightly larger. On the night of Nov. 21- 22, the waning gibbous moon passes just S of Jupiter.

Though on the far side of our solar system from Earth right now, and, therefore, smaller, Mars ( mag. 1.4) should be identifiable as a ruddy- coloured “star” as its rises in the east around 1: 30 a. m.

Mercury makes its best morning apparition of the year when it climbs into the eastern, pre- dawn sky. Shining at mag. - 0.6, Mercury should be noticeable in the ESE sky about 45 minutes before dawn.

Once you have located Mercury, you can use this bright planet to locate Saturn. On the mornings of Nov. 25- 26, these two planets will be less than 1

... Cont. from C1 degree apart. On Nov. 25, Mercury will be the higher of the two planets, with the positions switched ( Saturn above) on the morning of Nov. 26. It’s a great photo op.

Unfortunately this time around, the famous Leonid meteor shower which is usually so reliable in terms of numbers and brightness of its meteors, will be washed out by the light of the full moon, which occurs mid- morning of Nov. 17, just a few hours after the Leonids are due to peak.

Observers may still see a few of these wonderfully bright meteors if they position themselves next to trees or a building so as to block the moon. Leonids regularly strike Earth’s atmosphere at speeds in excess of 250,000 kms/ hr, producing more bright fireballs than most other meteor showers. They are always worth watching, even under a full moon.

Speaking of full moons, this month’s was often referred to by early settlers as the “Beaver Moon” as this was the time of year when beavers were hunted to ensure a supply of warm furs. It was also sometimes called the “Frost Moon” for the frosts that appeared at this time.

Until next month, clear skies

and good hunting.

Nov. 10

1: 57 a. m.

Nov. 17

EVENTS ( AST)

— First quarter moon;

— Full moon; 11: 16 a. m.; Leonid meteor shower ( pre- dawn sky)

Nov. 22

— Moon at apogee ( farthest from Earth); 403,090 kms.; 5: 49 a. m.

Nov. 25

3: 28 p. m.

Nov. 28

— Last quarter moon;

— Comet ISON reaches perihelion ( closest to Sun); 1.16 million kms.; 3 p. m.