Other Earths - Goldilocks zone, light years, ideal conditions
Other Earths
Goldilocks zone, light years, ideal conditions
Astronomy Unit
Every day Earth gets a little more crowded. More and more people are born. Our air becomes a little less
clean. More and more cars let out gases. Every day we use up our resources. We chop down trees and
use fresh water. Every day, it becomes a little harder to live on Earth. This may feel a little sad. However,
every day, scientists are searching space for planets that are just like ours. They're looking for new
chances, fresh starts. Sometimes they find them.
What makes a planet like Earth? Earth is different from most in that it sits just far away enough from the
sun, but not too far. The Goldilocks zone is the ring around the sun that isn’t close enough to be too hot
for life and isn’t far enough to be too cold for life. Planets can be too hot, too cold, or just right. While
Venus is much too hot and Mars is much too cold, Earth is in the spot that is just right.
We need more than just the right weather to live on Earth. Earth's turning center makes a shield that
blocks the sun's rays from cooking us. The shifting plates push new earth up and pull old earth down to be
used again. Earth is also small enough to be rocky so we do not fall through it like we would on a bigger
gas planet. Ideal conditions are the best set of things for life like us to live. If the planet we find is
enough like Earth, if it blocks the sun, if it makes new land, if it's made of rock, then we might be able to
live on it. Now it’s just a matter of getting there . . .
We do not find planets like Earth very often. In 2013, we only found three. These are so far away that we
cannot tell what’s happening on them. A light year is how far light, the fastest thing we know about, can
go in one year. The closest Earth-like planet is at least 6-7 light years away. That may seem like good
news — it’s only 7 light years away! But there’s one little problem. We are not made of light! We don't
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Other Earths - Goldilocks zone, light years, ideal conditions
travel that fast.
So if the planets we might be able to live on are too far away for us to even see, why are we making such
a big deal about finding them? As it becomes more crowded and harder to breathe here on Earth, we
might someday have to try and reach a new place where we can live. Who knows? Your children’s
children’s children’s children might be able to find a way to get there. People may have to spend two or
three lifetimes on a spaceship,. though. Tell me. Would you live on a spaceship to save everyone on
Earth?
References:
NPR. “Scientists Estimate 20 Billion Earth-Like Planets In Our Galaxy” NPR, 2013.
< http://www.npr.org/blogs/thetwo-way/2013/11/04/243062655/scientists-estimate-20-billion-earth-likeplanets-in-our-galaxy>
Health and Science. “Kepler space telescope finds, Earth-size, potentially habitable planets are
common” Washington Post, 2013.
<http://www.washingtonpost.com/national/health-science/kepler-space-telescope-finds-earth-sizepotentially-habitable-planets-are-common/2013/11/04/49d782b4-4555-11e3-bf0c-cebf37c6f484_story.html
>
New Scientist. “Closest Earth-like planet may be half as far as previously thought” New Scientist,
2013.
<http://www.rawstory.com/rs/2013/03/13/closest-earth-like-planet-may-be-half-as-far-as-previouslythought/>
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