Page 186 - Innovator's Science-8

heat very effectively, creating a strong greenhouse effect This
Science phenomenon prevents heat from escaping into space, making Venus
Bytes
hotter than even Mercury, the
Testimony
The greenhouse effect planet closest to the Sun.
Sun
that allows planets like A similar greenhouse effect
Venus and Earth to retain Outgoing
Solar
heat does not work occurs on Earth too. Our Radiation Energy Greenhouse gases in Earth's
atmosphere trap heat
exactly like a greenhouse atmosphere contains gases
used for growing plants in like carbon dioxide that Atmosphere
colder climates. On Incoming Warming
Energy
planets, gases such as absorb heat radiated from the Effect
carbon dioxide in the planet after it warms up under
atmosphere absorb the Trapped
heat radia on emi ed by sunlight. This natural effect Energy
-Heat
Earth a er it has been helps regulate Earth’s
warmed by the Sun, temperature, making it
trapping the heat. Schematic of greenhouse effect on Earth
hospitable for life.

In contrast, a plant greenhouse traps warm air
because it is an enclosed structure, usually

made of glass. During the day, it warms up,
and the heat stays inside because the air
cannot escape easily. So, although both
systems keep things warm, they do so in

different ways. Greenhouse for plants

Fill in the Blanks:
Run Through
1. All life on Earth exists within a very thin outer layer called the _____________.
Intellectual Development
2. Earth's crust is as thin as the _____________ of an apple when compared to
the entire planet.
3. The planet _____________ is the hottest in the solar system due to its thick
atmosphere of carbon dioxide.
4. The greenhouse effect helps Earth retain _____________ and maintain a
suitable temperature for life.
5. Earth stays warm because its atmosphere traps heat using gases like
_____________ .

WHAT MAKES EARTH SUITABLE FOR LIFE?

One of the key reasons Earth can support life is its perfect placement within
the solar system. Its distance from the Sun is "just right"allowing

temperatures that keep water in its liquid form. If Earth were much closer, it
would be far too hot, causing all water to evaporate. On the other hand, if
Earth were farther away, it would be much colder, freezing all water. Either

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