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view), it’s like trying to find a needle in a haystack! Once
you’ve centered the object in the eyepiece, you can switch to
higher magnification (shorter focal length eyepiece), if you
wish.
The best rule of thumb with eyepiece selection is to start
with a low power, wide-field eyepiece, and then work your
way up in magnification. If the object looks better, try an even
higher magnification. If the object looks worse, then back off
the magnification a little by using a lower-power eyepiece.
What to Expect
So what will you see with your telescope? You should be
able to see bands on Jupiter, the rings of Saturn, craters on
the Moon, the waxing and waning of Venus, and many bright
deep-sky objects. Do not expect to see color as you do in
NASA photos, since those are taken with long-exposure
cameras and have “false color” added. Our eyes are not sen-
sitive enough to see color in deep-sky objects except in a
few of the brightest ones.
Remember that you are seeing these objects using your own
telescope with your own eyes! The object you see in your
eyepiece is in real-time, and not some conveniently provided
image from an expensive space probe. Each session with
your telescope will be a learning experience. Each time you
work with your telescope it will get easier to use, and stellar
objects will become easier to find. Take it from us, there is
big difference between looking at a well-made full-color
NASA image of a deep-sky object in a lit room during the
daytime, and seeing that same object in your telescope at
night. One can merely be a pretty image someone gave to
you. The other is an experience you will never forget!
Objects to Observe
Now that you are all set up and ready to go, one critical deci-
sion must be made: what to look at?
A. The Moon
With its rocky surface, the Moon is one of the easiest and
most interesting targets to view with your telescope. Lunar
craters, marias, and even mountain ranges can all be clearly
seen from a distance of 238,000 miles away! With its ever-
changing phases, you’ll get a new view of the Moon every
night. The best time to observe our one and only natural
satellite is during a partial phase, that is, when the Moon is
NOT full. During partial phases, shadows are cast on the
surface, which reveal more detail, especially right along the
border between the dark and light portions of the disk (called
the “terminator”). A full Moon is too bright and devoid of sur-
face shadows to yield a pleasing view. Make sure to observe
the Moon when it is well above the horizon to get the
sharpest images.
Use an optional Moon filter to dim the Moon when it is very
bright. It simply threads onto the bottom of the eyepieces
(you must first remove the eyepiece from the focuser to
attach a filter). You’ll find that the Moon filter improves view-
ing comfort, and also helps to bring out subtle features on
the lunar surface.
B. The Sun
You can change your nighttime telescope into a daytime Sun
viewer by installing an optional full-aperture solar filter over
the front opening of the ShortTube 4.5 EQ. The primary
attraction is sunspots, which change shape, appearance,
and location daily. Sunspots are directly related to magnetic
activity in the Sun. Many observers like to make drawings of
sunspots to monitor how the Sun is changing from day to
day.
Important Note: Do not look at the Sun with any optical
instrument without a professionally made solar filter, or
permanent eye damage could result.
C. The Planets
The planets don’t stay put like the stars, so to find them you
should refer to Sky Calendar at our website (telescope.com),
or to char ts published monthly in Astronomy, Sky &
Telescope, or other astronomy magazines. Venus, Mars,
Jupiter, and Saturn are the brightest objects in the sky after
the Sun and the Moon. Your ShortTube 4.5 EQ is capable of
showing you these planets in some detail. Other planets may
be visible but will likely appear star-like. Because planets are
quite small in apparent size, optional higher-power eyepieces
are recommended and often needed for detailed observa-
tions. Not all the planets are generally visible at any one time.
JUPITER: The largest planet, Jupiter, is a great subject for
observation. You can see the disk of the giant planet and
watch the ever-changing positions of its four largest
moons—Io, Callisto, Europa, and Ganymede.
SATURN: The ringed planet is a breathtaking sight when it is
well positioned. The tilt angle of the rings varies over a peri-
od of many years; sometimes they are seen edge-on, while
at other times they are broadside and look like giant “ears”
on each side of Saturn’s disk. A steady atmosphere (good
seeing) is necessary for a good view. You will probably see a
bright “star” close by, which is Saturn’s brightest moon, Titan.
VENUS: At its brightest, Venus is the most luminous object
in the sky, excluding the Sun and the Moon. It is so bright
that sometimes it is visible to the naked eye during full day-
light! Ironically, Venus appears as a thin crescent, not a full
disk, when at its peak brightness. Because it is so close to
the Sun, it never wanders too far from the morning or
evening horizon. No surface markings can be seen on
Venus, which is always shrouded in dense clouds.
MARS: The Red Planet makes its closest approach to Earth
every two years. During close approaches you’ll see a red
disk, and may be able to see the polar ice cap.
D. The Stars
Stars will appear like twinkling points of light. Even powerful
telescopes cannot magnify stars to appear as more than a
point of light. You can, however, enjoy the different colors of
the stars and locate many pretty double and multiple stars.
The famous “Double-Double” in the constellation Lyra and
the gorgeous two-color double star Albireo in Cygnus are
favorites. Defocusing a star slightly can help bring out its
color.
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