solar system

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Transcript solar system

What is a constellation
A group of stars is known as a
constellation.
The Great Nebula (M42) in the constellation Orion, 1,600 light-years
from the earth, consists of bright and dark masses of gas and dust
where stars are in the process of being born. e.
Ronald Royer/Science Source/Photo Researchers, Inc.[1]
[1]"Orion Nebula," Microsoft® Encarta® Encyclopedia 2000. © 1993-1999 Microsoft
Corporation. All rights reserved.
The various constellations with their
shapes seen during the year
Hanging down from Orion's belt is his sword that is made up of
three fainter stars. The central "star" of the sword is actually not a
star at all, but the Great Orion Nebula, one of the regions most
studied by astronomers in the whole sky. Nearby is the
Horsehead Nebula (IC 434), which is a swirl of dark dust in front
of a bright nebula.
hat is the difference between a revolution and rotation
What is the difference between
a revolution and rotation
REVOLUTION =SEASONS
The changing seasons are caused by
the changing position of the Earth in
relation to the sun.seasons keep
changing because the tilt of the Earth's
axis never changes while the Earth
circles the sun. One way to understand
this is to picture which way the tilt of the
axis causes the North Pole to slant at
different times of the year.
WHAT IS A SEASON
A SEASON is one of the four periods of the year. Each
eason--spring, summer, autumn, and winter--lasts about
hree months and brings changes in temperature, weather,
nd the length of daylight.
During the spring, the days are warm in middle parts of the
Northern Hemiphere, the northern half of the Earth.
Summer follows with hot days and warm nights. In
utumn, the days become cooler, leading to the cold of
winter. The four periods are called climatic seasons when
ased on these temperature and weather changes.
n the Southern Hemisphere, the climatic seasons differ by
bout six months. This hemisphere has summer when the
Northern Hemisphere has winter.
DO SEASONS OCCUR EVERY
WHERE?
• Some regions do not have all four
climatic seasons.
• In parts of the tropics, for example,
temperatures change little. But the
amount of rainfall varies greatly, so
that these regions have a wet season
and a dry season.
• The polar regions, on the other hand,
have a light season and a dark
season. In these parts of the world,
the sun shines almost all the time in
summer and almost never during the
winter.
What is rotation
when an object
moves on its
own axis it is
called
rotation .
This phenomenon
causes day and night