2. • All living things on Earth are dependent on the sun to
stay alive.
All life on Earth needs the sun to thrive and grow. All
energy that humans consume originates from the sun,
either directly or indirectly.
• Plants need sunlight to grow. Humans need plants, or
animals that eat plants, to stay alive. Also, electricity is
generated by burning oil or coal, which is essentially
ancient plants. (Some electricity is created using solar
or wind energy, which is also dependent on the sun.) If
the sun were to disappear, all plants and animals
would eventually die.
3. • The sun is a star.
• The sun is a star, but appears to be much
larger because it is so close to earth. It is one
of the 100 billion stars in the Milky Way
galaxy. It is approximately 93 million miles
from Earth.
4. • The sun is the largest object in our solar
system.
• The sun is larger than all of the planets. Its
radius is approximately 432,000 miles. This is
nearly 109 times as large as the Earth. It is
about 865,000 miles across.
5. • The sun is incredibly hot.
• The outer part of the sun is about 10,000
degrees Fahrenheit. That is about fifty times
hotter than the temperature at which water
boils. It is so hot that all metals would be
vaporized on the sun.
6. • The sun is about 70% hydrogen and 28%
helium.
• The core of the sun converts hydrogen to
helium. The sun is basically a giant ball of gas.
7. • All of the planets in our solar system revolve
around the sun.
• The Earth, as well as other planets such as
Mars, Venus, Saturn, and Jupiter, move
around the sun. The length of time it takes a
planet to revolve around the sun is referred to
as a year. There are 365 days in one Earth
year. The length of years vary on other
planets.
8. • The four seasons on Earth are determined by
how close the Earth is to the sun.
Each year, as the Earth revolves around the
sun, the seasons change. It is hottest in the
summer when it is closest to the sun.
However, it is not always the same seasons on
all parts of Earth. Some parts of the Earth are
closer to the sun at different times.
9. • It takes 8.3 minutes for light from the sun to
reach the Earth.
• When you see the sun, you are actually seeing
what it looked like 8.3 minutes ago. It takes
that amount of time for light to reach the
Earth.
10. • It takes 8.3 minutes for light from the sun to
reach the Earth.
• When you see the sun, you are actually seeing
what it looked like 8.3 minutes ago. It takes
that amount of time for light to reach the
Earth.
