Bushnell NORTHSTAR GOTO 78-8890 - Manual (Page 5)

M
HELPFUL HINTS
9.
M
ENJOYING YOUR NEW TELESCOPE
8.
1. First determine your targeted object. Any bright object in the night sky is a good starting point.
One of the favorite starting points in astronomy is the moon. This is an object sure to please
any budding astronomer or experienced veteran. When you have developed proficiency at this
level, other objects become good targets. Saturn, Mars, Jupiter, and Venus are good second steps
to take.
2. The first thing you need to do after assembling the telescope as planned is center the desired object
in the finderscope’s cross hairs. Provided you did a reasonable job aligning the finderscope, a quick
look through the main telescope tube at low power should reveal the same image. With the lowest
power eyepiece (the one with the largest number printed on it) you should be able to focus the
same image that you saw through the finderscope. Avoid the temptation to move directly to the
highest power. The low power eyepiece will give you a wider field of view, and brighter image—thus
making it very easy to find your target object. At this point with a focused image in both scopes,
you’ve passed the first obstacle. If you don’t see an image after attempting to focus it in, you
might consider aligning your finderscope again. Once you pass this step, you’ll will enjoy the time
spent ensuring a good alignment. Every object you center in the finderscope will be easily found in
the main telescope tube, which is important for continuing your exploration of the night sky.
3. The low power eyepieces are perfect for viewing the full moon, planets, star clusters, nebulae, and
even constellations. These should build your foundation. However, for more detail, try bumping
up in magnification to higher power eyepieces on some of these objects. During calm and crisp
nights, the light/dark separation line on the moon (called the "Terminator") is marvelous at high
power. You can see mountains, ridges and craters jump out at you due to the highlights. Similarly,
you can move up to higher magnifications on the planets and nebulae. Star clusters and individual
stars are best viewed through the low power no matter what.
4. The recurring astronomical theater we call the night sky is an ever-changing billboard. In other
words, the same movie does not play all the time. Rather, the positions of the stars change not
only hourly as they seem to rise and set, but also throughout the year. As the earth orbits the sun
our perspective on the stars changes on a yearly cycle about that orbit. The reason the sky seems
to move daily just as the sun and the moon "move" across our sky is that the earth is rotating about
its axis. As a result you may notice that after a few minutes or a few seconds depending on what
power you are viewing at, the objects in your telescope will move. At higher magnifications especially,
you will notice that the moon or Jupiter will "race" right out of the field of view. To compensate,
just move your telescope to "track" it in the necessary path.
1. Your telescope is a very sensitive instrument. For best results and fewer vibrations set
your telescope up on a level location on the ground rather than your concrete
driveway or your wooden deck. This will provide a more stable foundation for viewing,
especially if you’ve drawn a crowd with your new telescope.
2. If possible view from a location that has relatively few lights. This will allow you to see
much fainter objects. You’d be surprised how much more you’ll see from your local lake
or park when compared to a backyard in the city.
3. Using your telescope out a window is NEVER recommended.
4. View objects that are high in the sky if possible. Waiting until the object rises well
above the horizon will provide a brighter and crisper image. Objects on the horizon
are viewed through several layers of earth’s atmosphere. Ever wonder why the
moon appears orange as it sets on the horizon? It’s because you are looking
through a considerable more amount of atmosphere than you would directly
overhead. (Note: If objects high in the sky are distorted or wavy, you are probably
viewing on a very humid night.) During nights of unstable atmosphere, viewing
through a telescope can be frustrating if not impossible. Astronomers refer to crisp,
clear nights as nights of "good seeing."
78-8890 1LIM.indd 8-9 6/1/04 11:20:07 AM