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- Let's take a quick trip
through the planets in our solar system,
with our last stop
at the dwarf planet Pluto.
So how far is the Sun from Pluto?
It's this.
Does this number mean anything to you?
How can scientists possibly work with numbers this big?
- The end of the solar system is something like
5 trillion miles away.
That's a lot of zeroes.
To manage such a huge number,
we need to scale things down to more manageable numbers.
"AU" is "astronomical unit."
It's the distance between the Earth and the Sun,
about 93 million miles,
and it's a convenient yardstick
to measure other distances throughout the solar system.
And the AU is very convenient.
So the size of the solar system in AU
is about 50,000 AU.
- One way to get a better idea of the distance
between the Sun and Pluto is to compare it
to something most of us have seen and is familiar,
like a football field.
Let's start by placing the Sun at the goal line
and Earth at a distance of 1 AU,
which is at the second yard line on a football field.
We'll drop in inner planets first to scale,
using astronomical units.
Mercury and Venus is less than 1 AU from the Sun.
Mars is beyond Earth's orbit, at a distance of 1.5 AU.
The outer planets begin with Jupiter, at 5.2 AU,
and end with Neptune, at 30 AU,
which is a little more than half a football field away.
And let's not forget the dwarf planet Pluto.
At 39.5 AUs, it's 79 yards away from the Sun
on our football field.
Hmm, I wonder where
the Kuiper Belt and the Oort Cloud
fit on this scale.
- The Kuiper Belt is about 30-50 AUs away from the sun.
The Oort Cloud wouldn't even be in the stadium.
It would be a couple miles away,
and it would extend as much as 50 miles away.
- Our solar system is so vast.
Math and scaling helps us shrink the solar system down
to a physical model that we can understand.
To learn more about our solar system,
check out this website:
Thanks for watching.
See you next time on "Real World."
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