Meade Instruments TerraStar 60 - Manual (Page 15)

objects are easiest to see under dark skies.
But it is still possible to observe even in
a city.
Surf the Web and visit your local library:
The internet contains a huge amount of
astronomical information, both for children
and adults. Check out astronomy books from
your library. Look for star charts—these are
available on a monthly basis in
Astronomy
and Sky and Telescope magazines.
HAVE A GOOD TIME,
ASTRONOMY IS FUN!
SPECIFICATIONS
Optical tube focal length . . . . . . . . . 700mm
Objective lens diameter. . . 60mm (2.4 inch)
Focal ratio. . . . . . . . . . . . . . . . . . . . . . . f/11.7
Mounting type . . . . . . . . . . . . . . . Altazimuth
What do the specifications mean?
Optical tube focal length is simply a
measurement of the length of the optical
tube. In other words, this is the distance
light travels in the telescope before being
brought to focus in you eyepiece. Your tube is
700mm long.
Objective lens diameter is how big the
lens is on your scope. Telescopes are
always described by how large their
objective lens is. Your telescope is 60mm
or 2.4 inches. Other telescopes are 90mm,
8 inches, 16 inches, or even 3 feet in
diameter. The Hubble Telescope’s objective
lens has a diameter of 2.4 meters (that’s
7.8 feet across!).
The focal ratio helps determine how
fast the photographic speed of a
telescope is. The lower the focal ratio
number, the faster the exposure. f/5 is
faster than f/10. The faster the ratio, the
faster exposure time is needed when a
camera is hooked up to the telescope. Your
telescope has slower focal ratio at f/11.7.
Sometimes, astronomers use focal reducers
to make slow exposure telescopes have
faster focal ratios.
Altaz mounting simply means your telescope
moves up and down (altitude or “alt”), and
side to side, (azimuth or “az”). Other
Looking at or near the Sun will cause irreversible damage to your eye. Do not point this telescope at or near the Sun. Do not look through the telescope as it is moving.
JOIN AN ASTRONOMY CLUB, ATTEND A STAR PARTY
One of the best ways to increase your knowledge of
astronomy is to join an astronomy club. Check your local
newspaper, school, library, or telescope dealer/ store to
find out if there’s a club in your area.
Many groups also hold regularly scheduled Star Parties
at which you can check out and observe with many
different telescopes and other pieces of astronomical
equipment. Magazines such as
Sky and Telescope and
Astronomy print schedules for many popular Star Parties
around the United States and Canada.
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