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With the end of daylight savings time and the approaching winter solstice, November
evenings offer several hours of darkness to view our glorious night sky
while still getting a full night’s sleep. Conversely you can rise a bit
earlier and still catch Venus, Saturn, Mars and even Mercury before the
sun rises.
In early November Mars rises above the east north-east horizon about
9:30 PM and by late November you might notice it as early as 8:30 PM.
The beautiful Pleiades star cluster will already be to the upper right
of Mars. Every 26 months earth overtakes the red planet on our shorter
path around the sun. This time we will be closest to Mars on December
19 but November and January evenings will still offer opportunities to
gaze on our close celestial neighbour.
Of all the planets, Mars mostly closely resembles the earth with a
visible surface, with seasons and a 24 hour and 37 minute day. With a
good telescope and a clear night you might be able to see a white polar
cap and some surface markings on Mars during this year’s approach.
I regularly field calls about the bright star in the east before
dawn. Being close to the sun and totally covered with clouds, Venus
reflects most of its sunlight back into space, making it the brightest
celestial object after the sun and moon. With binoculars or in a
telescope Venus now appears like a first quarter moon as half of its
disc is illuminated. Saturn floats above and to the south of Venus in
the morning sky and Mercury makes a brief appearance below Venus in
early November.
Last month we began some comments on astronomy equipment. Canadian
author and astronomer Terence Dickinson includes a section on
Stargazing Equipment in his popular NightWatch book. In a section
called “Trash-Scope Blues” he quotes a caller: “Am I doing something
wrong, or is it this telescope?…It doesn’t seem to focus, and I am
never sure what I am pointing at.” I was speaking with another
frustrated owner of a $200 department-store telescope, the kind that
comes in an attractive package announcing a 450-Power Astronomical
Telescope, embellished with color photographs of comets and
nebulas….aptly called a “Christmas trash scope”. Dickinson continues,
“The classic trash scope priced at $300 or less is designed not for
ease of use but to appeal to rank beginners and well-meaning gift
buyers.” Many have been turned away from a wonderful journey of
discovery by a bad case of “trash scope blues.
All the larger telescopes around the world, including the Hubble, are
reflectors, often referred to as Newtonians. They use a concave mirror
to collect the light and bring it to a focus. For an equal amount of
money you will almost always get a larger telescope by purchasing a
reflector rather than a refractor. I usually recommend this type of
telescope with at least a 5 or 6 inch diameter mirror for someone
beginning in astronomy. A Dobsonian mount will be somewhat less
expensive and simpler to use than a tripod mounted or equatorial
mounted telescope but these are rarely offered in department stores. A
six or eight inch mirror in a reflector on a Dobsonian mount is a
recommended beginner scope by Terence Dickinson. They sell in the range
of $300 to $400. A refractor is a traditional looking scope with lenses
and gives sharp, clear views of the moon and planets and often can be a
good daytime telescope if it is on a tripod and offers a “right side
up” view. A refractor cannot be built as large as a reflector and will
be limited in its views of deep sky objects such as nebulas and
galaxies. Find a telescope dealer who can help you clarify what you
plan to view with the telescope and who can tell you the advantages and
disadvantages of each scope.
While evenings are cooler, for the next several months Canadians can
be lost in wonder and awe at the splendors of the heavens above.
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