Over the years when I’ve spoken with many other amateur astronomers
about their interest in the sky, most have said that it could be traced
back to receiving their first telescope at Christmas.
With the winter holidays
now behind us, perhaps you fall into this category. If this is the
case, then please read this article carefully, for you are now at a very
important crossroad.
now behind us, perhaps you fall into this category. If this is the
case, then please read this article carefully, for you are now at a very
important crossroad.
While it is true that many have been hooked on skywatching
for life by viewing the wonders of the night sky through their first
scope, it is also true that many others have had their initial
enthusiasm for astronomy severely dampened by their first telescope — particularly if they didn't know how to properly use it, and any initial pleasure soon turns to frustration.
So, now is the appropriate time to talk about how to best take advantage of your new instrument.
Learn your way around
Before anything else, if you have not already done so, I would invest
in a couple of good books on the stars and constellations. As the late
George Lovi (1939-1993), a longtime columnist of Sky & Telescope
magazine, once wrote: "First spend some time learning the sky with your
own personal optics — the set nature mounted in your head." [Skywatching Events for February 2012]
in a couple of good books on the stars and constellations. As the late
George Lovi (1939-1993), a longtime columnist of Sky & Telescope
magazine, once wrote: "First spend some time learning the sky with your
own personal optics — the set nature mounted in your head." [Skywatching Events for February 2012]
If you haven't yet opened the box that contains your telescope, good!
From 45 years of both personal observing and teaching many others, it’s
my belief that you should not hastily rush outside with a telescope
before even knowing what's in the sky or what to look at. It's not
unlike buying a catamaran if you've never sailed before.
When you finally start setting up your telescope,
take whatever time is needed to learn its use and operation. Be sure
that you have assembled everything with great care. In the beginning,
practice how to aim and focus your new instrument, not on the night sky,
but on daytime terrestrial objects. Not only are these daytime targets
bright and easy to see, but unlike night sky objects, they will not
drift out of your field of view because of the rotation of the Earth.
Was your new instrument advertised by the manufacturer as promising
"spectacular views" of the moon or the rings of Saturn at magnifications
of, say, 500-power or more? Unfortunately, too many uninitiated
amateurs are "power happy" (can we call this malady "poweritis?"). High power dilutes the brightness of an image, as well as aggravates any unsteadiness of detail. [Video: Types of Telescopes - Which is Right for You?]
happy" (can we call this malady "poweritis?"). High power dilutes the brightness of an image, as well as aggravates any unsteadiness of detail. [Video: Types of Telescopes - Which is Right for You?]
So, always remember as a general rule of thumb: the maximum amount of
magnification for any telescope is 50-power per inch of aperture. If you
have, for example, a 6-inch reflector, 300-power is as high as you should ever attempt to go; the maximum for a 3-inch refractor should be 150-power.
"But wait a minute," you may protest, "my telescope comes with a
special Barlow lens, that the manufacturer promises will double or even
triple the magnification of my eyepiece."
True enough. In fact, the aforementioned 500-power is likely achieved
by pushing the scope's highest power eyepiece with that very same Barlow
lens (a diverging lens named for its creator, the English engineer
Peter Barlow), which ultimately will result in a dim, impossibly fuzzy
image.
A little lesson about power
If you’re a beginner, you need to understand that using a Barlow lens
is similar to enlarging a photograph. The negative — like a telescope's
image — contains only so much detail, which can be blown up only so far
before all you can see is fuzz!
So, if you have purchased a 3-inch telescope — even if it is blessed with perfect optics — the claim of 500-power is more than three times the limit of the most practical magnification that it can provide.
Truth be told, you'll probably be surprised to discover that your most
pleasing views with your new instrument will come at much lower powers.
Low power, in fact, makes a telescope much more convenient to handle,
and if your telescope mount or tripod is a bit shaky, as least lower
powers will not magnify "the shakes" as much.
Personally, I’ve always felt that the most pleasing views with your
scope will come at one-half of its maximum possible magnification. So,
for that 6-inch telescope, use 150-power, and for a 3-inch telescope,
try 75-power.
One other thing that should be mentioned is in regard to solar viewing.
Some department store telescopes — especially imported varieties — may
include a dark glass that is designed to screw into the eyepiece of the
scope.
Supposedly, this filter is to be used to view the sun. If your telescope came with such a device, discard it immediately!
Unfortunately, by directing your telescope toward the sun
its light and heat are intensified tremendously when it reaches your
eyepiece. As such, there is an ongoing threat that the dark glass will
be heated to a point where it will suddenly crack. Should your eye be
looking through the eyepiece at the time, you likely will not have
enough time to turn away. The end result can be partialor total
blindness. Never, ever, look directly at the sun at any time with your telescope. [10 Most Popular Skywatching Misconceptions Explained]
its light and heat are intensified tremendously when it reaches your
eyepiece. As such, there is an ongoing threat that the dark glass will
be heated to a point where it will suddenly crack. Should your eye be
looking through the eyepiece at the time, you likely will not have
enough time to turn away. The end result can be partialor total
blindness. Never, ever, look directly at the sun at any time with your telescope. [10 Most Popular Skywatching Misconceptions Explained]
If you do wish to observe the sun, the only way to go is to project its enlarged image onto a white card or screen.
What’s up there?
On February 26, 2012, the Moon will be close to the planets Venus and Jupiter.Credit: Starry Night Software
So what is there to see? Probably the most rewarding object is the moon. It is bright, easy to locate and filled with fascinating detail.
Despite its tremendous brilliance, Venus is a bit of a disappointment right now as it will appear as merely a brilliant blob of light.
That will change in the coming weeks as it grows in size and will mimic
the changing phases of the moon, appearing half illuminated late in
March and then as a thinning crescent during April and May.
Jupiter is high and dazzling in the southern sky at nightfall and is unmistakable; its four bright moons are a constantly changing target even in binoculars.
Another target is Mars, appearing as a brilliant fiery-colored star in
the eastern sky during the mid-to-late evening hours and is now
approaching Earth and getting increasingly brighter with each passing
night.
Rising in the east-southeast sky soon after midnight is the planet
Saturn (whose famous rings can be recognized with a magnification as low
as 30-power).
The brilliant starry scene in the southern sky during the early evening
hours contains innumerable treats, including the Pleiades and Hyades
Star Clusters and the Great Nebula of Orion. Indeed, there’s an entire
universe of stars — double, multiple and all highly beautiful — as well
as other nebulas and galaxies for you to explore. The choices are
virtually inexhaustible.
Welcome to the club!
And as a final piece of advice, make an effort to contact a local astronomy club. You can probably locate the one nearest to you by visiting the website of the Astronomical League
(AL) and clicking on "Member Societies." The AL, which is by far the
largest national organization of amateur astronomers, is composed of
scores of local amateur astronomical clubs and groups, totaling
thousands of individuals.
, make an effort to contact a local astronomy club. You can probably locate the one nearest to you by visiting the website of the Astronomical League
(AL) and clicking on "Member Societies." The AL, which is by far the
largest national organization of amateur astronomers, is composed of
scores of local amateur astronomical clubs and groups, totaling
thousands of individuals.
By attending local club meetings, you'll get to meet a number of fellow sky gazers
who can offer you valuable advice. If you own a telescope, but are
experiencing problems with it, there is no better place to go than an
astronomy club, whose members can offer assistance and helpful
suggestions. Besides, you'll also find camaraderie and the opportunity
to spend time with other people from different walks of life who all
share the same love for the nighttime sky.
So, good luck and enjoy your new telescope!
Joe Rao serves as an instructor and guest lecturer at New York's
Hayden Planetarium. He writes about astronomy for The New York Times and
other publications, and he is also an on-camera meteorologist for News
12 Westchester, N.Y.
