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Often we think of astronomy as an evening activity but a number of
celestial highlights occur this October in pre-dawn hours. Just as
Venus took centre stage earlier this year in the evening sky, it now
blazes high in the eastern morning sky. On October 5 the moon passes
close to the Beehive Star Cluster. While visible to the naked eye,
binoculars will reveal about a dozen bright stars and several other
fainter stars in close proximity to the waning crescent moon.
As darkness falls earlier in October evenings, a beautiful river
of light flows overhead from northeast to southwest. Binoculars or a
small telescope will reveal hundreds and thousands of stars as you peer
toward the centre of our home galaxy, the Milky Way. As you follow this
concentration of stars towards the southwestern horizon you may notice
several different star clouds. From a dark sky area you may notice the
river of light accompanied by a dark “river bank” running to the west
of the Milky Way. This area, while not as spectacular as the star
fields, is a concentration of interstellar dust blocking out background
stars. Far from the centre of the galaxy one special star is
accompanied by eight planets and a special life form, human beings, who
stand mesmerized by the spectacular view of other stars and galactic
material. Take the opportunity on a dark night to gaze southward with
binoculars or a telescope into this area of the Milky Way. You will see
several star clusters and nebula whose light began its journey to us
hundreds of years ago.
In October Saturn emerges from behind the sun into the morning sky. On
Sunday of our Thanksgiving weekend, look in the morning sky for a
gathering of Venus, Saturn and the moon. By mid month Saturn and Venus
are paired nicely from earth’s vantage point. Venus is relatively close
to us and orbits the sun inside earth’s orbit while Saturn orbits ten
times our distance from the Sun. The red planet, Mars, is also visible
high overhead in the morning sky and will appear in the evening sky
later this year.
As we approach the gift giving season we are often asked for
recommendations on telescopes and binoculars. The first piece of advice
is to avoid the temptation to purchase something off the shelf of a
department store based on the colourful pictures of Saturn and a nebula
while also offering motorized tracking and magnification of several
hundreds. Too many people have been turned away from a life-long,
fascinating hobby by a shaky mount, plastic focuser, poor optics, small
aperature and bargain price of these scopes.
Prices of good telescopes have come down significantly in recent years
and it is possible to now purchase a quality instrument that will show
Saturn’s rings, four of Jupiter’s moons and dozens of star clusters,
galaxies and nebula for $300 to $500. In astronomy our primary
commodity is light so, generally, if you collect more light, you will
have a better view. A 6 inch telescope collects twice the light of a
four inch telescope and will give you better views of star clusters and
most planets. Most telescopes smaller than 4 inches or 100 millimeters
will work well on the moon but usually offer disappointing views of
planets and stars. Next month we will compare “refractors” to
“reflectors” for their advantages and disadvantages. However, if you
don’t have a telescope, begin your lifelong hobby with binoculars of no
more than ten power. These will give you a good, wide-field view of the
heavens and prepare you well for ownership of a telescope.
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