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National Geographic NG55CS Instructions And Owner's Manual page 6

Maksutov-cassegrain telescope

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WHAT TO LOOK FOR IN THE NIGHT SKY
There is a whole universe of objects you could view at night, so where do you start?
We recommend starting with the most prominent objects first.
The moon
The moon is the easiest target to find at night. When the moon is in full position, it
bathes the night with a silvery light that washes the sky of all but the brightest objects.
The best time to view the moon is not when it is full, but rather when it is less than half
full. The dividing line between dark and light on the moon, called the terminator, shows
the best detail in the craters and mountains.
The planets
The planets, our solar system companions, range in size and substance from moon-size
rocky bodies to giant gas balls, which could hold Earth 1,000 times over. To find the
planets, you will need information about their times of visibility. An astronomy magazine
will give you the locations of the planets as they change position from month to month.
The Internet is also an excellent source of information, offering star charts, maps, and
more!
The popular and more familiar constellations often provide the easiest landmarks to
help find the planet's locations and paths of orbit. Most people have looked up at the
sky at night and seen some of the planets without even realizing it. A planet looks like a
bright star but does not twinkle like a star does; it looks like a tiny ball. Venus, Mars,
Jupiter, and Saturn are the easiest planets to view. Mercury is dimmer, usually below
the horizon, and more challenging to find.
Each of the planets provides interesting views. Venus is covered with clouds so all that
is visible is an extremely bright light, the brightest next to the moon. However, Venus,
like the moon, goes through phases. As it travels around the sun, different areas of its
surface are illuminated, producing crescent shapes of varying sizes. Mars is the red
planet. When it is above the horizon, it is noticeably red and stands out like a beacon in
the night sky. The apparent brightness of Mars varies as the planet orbits around the
sun and throughout its period of visiblity, it will look brighter or dimmer depending on its
distance from Earth.
Jupiter is the largest planet in our solar system and the second brightest next to Venus.
Jupiter has many moons, four of which are often visible through your telescope when
viewing conditions permit. As you watch them throughout the evening, you will see that
they change position relative to each other and to Jupiter. It is possible with careful
planning to actually see one of the moons disappear either in front of or behind Jupiter
as it orbits around the planet.
Saturn, the second largest planet, is not as bright as Jupiter and so its moons are not as
visible through small telescopes. The large rings that encircle Saturn are spectacular to
observe, however.
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