Orion SPACEPROBE 9851 - Manual (Page 14)

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between the dark and light portions of the disk (called the
“terminator”). A full Moon is too bright and devoid of surface
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 SpaceProbe 130mm EQ. The prima-
ry 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. Leave the cover
caps on the finder scope, or better yet, remove the finder
scope from the telescope tube when solar viewing.
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 charts 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 SpaceProbe 130mm 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 need-
ed for detailed observations. 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. higher-power eyepieces
should bring out the cloud bands on the planet’s disk.
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 daylight!
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. To see sur-
face detail on Mars, you will need a high-power eyepiece and
very steady air!
E. 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.
F. Deep-Sky Objects
Under dark skies, you can observe a wealth of fascinating
deep-sky objects, including gaseous nebulas, open and
globular star clusters, and a variety of different types of gal-
axies. Most deep-sky objects are very faint, so it is important
that you find an observing site well away from light pollution.
Take plenty of time to let your eyes adjust to the darkness.
Do not expect these subjects to appear like the photographs
you see in books and magazines; most will look like dim gray
smudges. Our eyes are not sensitive enough to see color in
deep-sky objects except in a few of the brightest ones. But
as you become more experienced and your observing skills
get sharper, you will be able to ferret out more and more
subtle details and structure.
How to Find Deep-Sky Objects: Star Hopping
Star hopping, as it is called by astronomers, is perhaps the
simplest way to hunt down deep-sky objects to view in the
night sky. It entails first pointing the telescope at a star close
to the object you wish to observe, and then progressing to
other stars closer and closer to the object until it is in the
field of view of the eyepiece. It is a very intuitive technique
that has been employed for hundreds of years by profession-
al and amateur astronomers alike. Keep in mind, as with any
new task, that star hopping may seem challenging at first,
but will become easier over time and with practice.
To starhop, only a minimal amount of additional equipment
is necessary. A star chart or atlas that shows stars to at least
magnitude 5 is required. Select one that shows the positions
of many deep-sky objects, so you will have a lot of options to
choose from. If you do not know the positions of the constel-
lations in the night sky, you will need to get a planisphere to
identify them.
Start by choosing bright objects to view. The brightness of
an object is measured by its visual magnitude; the brighter
an object, the lower its magnitude. Choose an object with
a visual magnitude of 9 or lower. Many beginners start with
the Messier objects, which represent some of the best and