Answer 1:
Thanks for your interesting question! All of
the planets in our solar system (the Earth
included) orbit the sun in an elliptical path - an
ellipse is a stretched circle, see the following
page for more information:
ellipse
The planets stay along this path - instead of
getting either closer to or further from the sun -
because each of the planets are predominantly
acted on by two forces that exactly oppose and
balance one another:
• The gravitational attraction between the sun and
each of the planets pulls the planets towards the
sun
• The rotational motion of the planets around the
sun leads to a force that pushes the planet away
from the sun
A good analogy for this motion is a tennis ball
that is attached to a string and swung in a circle
around you. When the ball first starts swinging,
the motion drives the tennis ball away from you
until the string gets tight. Once the string gets
tight, the tennis ball is "pulled" into a circular
path, which is similar to the way the sun's
gravitational force keeps the planets moving in an
elliptical path. You may also wish to check out
the following webpage for a diagram of these
forces and directions:
what
causes an orbit
I hope that this helps!
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