What is in the night sky?

What is up there in the sky? During the day, you can often see puffy clouds
floating high in the air, and a huge ball of gas called the
Sun. But when you look
up on a cloudless night, you can see other things up there: the Moon and many,
many stars. What are they? How many are there? How large are they? Can I
touch them? These are only some of the questions human beings have
pondered in the past and continue to ponder.

People have invented telescopes to see these planets and stars better. Stars
are very hot balls of gas. Planets look like stars to the naked eye, but if you look
at them every night for a month or so, you will notice how they move across the
sky. That is because they are moving in their orbit around the sun, just like
There are eight major planets in our solar system:
Mercury, Venus, Earth, and
Mars are the inner planets; Jupiter, Saturn, Uranus, and Neptune are the outer
planets. There are also smaller objects in the outer regions call "dwarf planets".
These include

How is the
Solar System measured?
When we look at things in the Solar System, we try to measure what we see.
This allows us to compare the many objects and to know how and where they
will move. To make it easy to share what we know with each other, a common
method is used. Most of the world now measures the Solar System using the
metric system. This system is a set of values that can be used to measure

The metric syste was first used in Europe during the eighteenth century. It was
meant to replace all of the older systems of measuring things, such as the
English system that used units such as feet, inches, pounds, and degrees
Fahrenheit. The use of the metric system has made it much easier for people to
agree on common sizes for things that are sold and to share information.

The types of values that are shown are length, mass, temperature, and time.
Length is used for values such as the size of a planet or the distance of a moon
from a planet. Mass can be thought of as the weight of something if it was on the
surface of the Earth. So if you weigh 30 kilogrammes on Earth, your mass is 30
kilogrammes. If you went somewhere where there was no gravity you would
weigh nothing at all, but you would still have a mass of 30 kg. So the weight
measures the pull of gravity on something with a given mass.

In the metric system, the length of something is measured in metres. A typical
adult is about 1.7 metres high. One metre, in the old English system, is a little
longer than 3 feet, 3 inches. The metre is sometimes shortened to an m. 'Metre'
is spelt 'meter' in the United States.

For longer distances, the kilometre is used ('kilometre' is spelt 'kilometre' in the
United States). A kilometre is a thousand metres. In the old English system, a
kilometre is equal to about five-eighths of a mile. It is often shortened to km.

Mass is usually measured in grams. A thousand grams is called a kilogramme.
The kilogramme is often shortened to kg. In the old English system, a
kilogramme is equal to about 2.2 pounds.

Finally, the temperature of something is measured in degrees Celsius. A degree
is sometimes written as a little circle to the right of a temperature value. So 25°
means twenty five degrees. The Celsius scale is based upon the temperatures
at which water freezes and boils. At 0° Celsius, water at the surface of the Earth
will freeze. When the temperature reaches 100° Celsius, water will begin to boil.
Celsius is often shortened to C.
Get Acrobat Reader Now
Join the Mailing List
Enter your name and email address below:
Subscribe  Unsubscribe 
Home   eBooks       Audio Books   Lit Arts    Language      Pre-K      Free ESL Resources     Online Games    Book of the Day       Game of the Day
AddThis Social Bookmark Button
Our Solar System
Sites for Teachers
Our Solar System
This comprehensive book
contains information on all
major planets, major star
constellations, space
exploration and our solar
system. Included are fact
sheets, fast facts,
wordsearches, crossword
puzzles, Q's & A's, Student
Activity Sheets,
Teacher/parent resources
and tips, lesson plans and
crafts and activities.  
Preview entire book 208
The Chinese lunar calendar dates back to the
second millennium BC. The Chinese calendar is
cyclical. Each cycle is made up of 12 years; after
the 12th year, the cycle is repeated.  
This book
contains comprehensive teacher/parent resources,
lesson plans and activities relating both to the
Chinese Zodiac and to the Chinese New Year. A
Fun interactive learning experience for Gr K-5  with
a particular focus on adjectives,  characteristics and
Preview the entire book here