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HE
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LANETS
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. Another great feature of Jupiter is its cloud belt. Jupiter is alive with weather activity
and its clouds have formed over time into belts visible through telescopes in the right atmospheric conditions.
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. The planet and its rings
appear pale yellow. The major division in the rings, the Cassini division, is possible to see if you keep the
telescope firmly in position.
Uranus and Neptune are the last of the solar system’s gas giants. They do not provide as spectacular a sight as
Jupiter or Saturn, but are nonetheless rewarding to see.
Beyond our solar system there are many more objects to be found. Galaxies, nebulae, and star clusters
abound!
FREQUENTLY ASKED QUESTIONS
1) How far can I see?
If you stand outside and look up at the night sky on a clear evening, you can see hundreds of stars without the
aid of your telescope. The telescope is a light-gathering instrument that magnifies the view—providing
significantly more detail and unveiling more stars, nebulae, and celestial objects. With the aid of a telescope,
you will be able to enjoy exciting views of Saturn’s rings, Jupiter’s major moons, the Orion Nebula, and much
more.
2) Why can’t I see anything through my telescope?
(a) If you see only grey or black when looking through your telescope, even after searching for an object to
view, it is very likely that you are using an eyepiece that is too powerful. To solve this problem always start with
the lowest power eyepiece first, and only insert the higher power eyepiece after you have located an object. (b)
The lens cap is still in place.
3) When I use my high-power eyepiece, everything looks much darker. Why?
As magnification in a telescope increases, brightness diminishes. Conversely, brightness increases when
magnification is reduced. If an image appears too dark or unclear, use a lower-powered eyepiece. Views of
small, bright objects are superior to those of large, dark, or blurry ones! Atmospheric conditions, air currents, as
well as light and air pollution also affect viewing quality.
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