National Geographic Bresser 9062000, Operating Instructions Manual

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Example: Let’s observe Jupiter.
Jupiter is visible in different parts of the world at different times depending on
location, time of year and local conditions.
If it is visible from your location and the telescope is aligned, you can navigate
to Jupiter by following these steps. Press the centre key (5) on your handbox
and select the 'Navigation' option. Move the selection bar with the arrow keys,
then press the centre key (5) for confirmation.
Next, select the 'Solar System' menu option and scroll with the arrow keys to
find Jupiter. Select Jupiter by pressing the centre key (5).
Once you select Jupiter, your telescope will automatically slew towards Jupiter.
When the telescope reaches Jupiter's position, a loud beeping noise will let you
know that the telescope is done moving. You may then begin your observation.
350 mm ÷ 20 mm = 17.5X
350 mm ÷ 10 mm = 35X
1250 mm ÷ 25 mm = 50X
1250 mm ÷ 12.5 mm = 100X
Formula for calculating magnification:
Focal length (Telescope) ÷ Focal length (Eyepiece) = Magnification
Examples:
Possible observation targets
The following section details several interesting and easy-to-find celestial
objects you may want to observe through your telescope.
The moon
The moon is Earth's only natural satellite.
Diameter: 3,476 km
Distance: 384,400 km from Earth (average)
The moon has been known to humans since prehistoric times. It is the second
brightest object in the sky, after the sun. Because the moon circles the Earth
once per month, the angle between the Earth, the moon and the sun is con-
stantly changing; one sees this change in the phases of the moon. The time
between two consecutive new moon phases is about 29.5 days (709 hours).
Constellation Orion: The Orion Nebula (M 42)
Right Ascension: 05
h
35
m
(hours : minutes)
Declination: -05° 22' (Degrees : minutes)
Distance: 1,344 light years from Earth
Though it is more than 1,344 light years from Earth, the Orion Nebula (M 42) is
the brightest diffuse nebula in the sky. It is visible even with the naked eye and
a worthwhile object for telescopes of all types and sizes. The nebula consists
of a gigantic cloud of hydrogen gas with a diameter of hundreds of light years.
Constellation Lyra: The Ring Nebula (M 57)
Right Ascension: 18
h
53
m
(hours : minutes)
Declination: +33° 02' (Degrees : minutes)
Distance: 2,412 light years from Earth
The famous Ring Nebula (M57) in the Lyra constellation is often viewed as the
prototype of a planetary nebula. It is one of the magnificent features of the
Northern Hemisphere's summer sky. Recent studies have shown that it is prob-
ably comprised of a ring (torus) of brightly shining material that surrounds the
central star (only visible with larger telescopes), and not a gas structure in the
form of a sphere or an ellipse. If you were to look at the Ring Nebula from the
side, it would look like the Dumbbell Nebula (M 27). When viewed from Earth,
we are looking directly at the pole of the nebula.
Constellation Vulpecula (Little Fox):
The Dumbbell Nebula (M 27)
Right Ascension: 19
h
59
m
(hours : minutes)
Declination: +22° 43' (Degrees : minutes)
Distance: 1,360 light years from Earth
The Dumbbell Nebula (M 27) was the first planetary nebula ever discovered.
On 12 July 1764, Charles Messier discovered this new and fascinating class
of objects. We see this object almost directly from its equatorial plane. If
we could see the Dumbbell Nebula from one of its poles, we would probably
see the shape of a ring, something very similar to what we know as the Ring
Nebula (M 57). In reasonably good weather, we can see this object well, even
with low magnification.