- [Instructor] You're probably familiar
with the major types of planets in our solar system.
You know, there are some smaller rocky planets
and some giant gas planets.
The rocky, or terrestrial ones are closer to our star,
the sun where it's much warmer, while the giant gas planets
are farther out in the cold.
But what about other planet systems we're finding out there
among the stars?
For the most part, they don't look a whole lot like ours.
Turns out, there doesn't seem to be a typical arrangement
for planetary systems.
Yep, all planetary systems might be weird.
Most other systems of planets
are certainly arranged differently.
Sure there are lots of planets out there the size
of Juipter and Neptune and Earth,
but their Jupiters and Neptunes can be way closer
to their stars than ours.
Some as close or closer than the orbit of Mercury.
So scientists who study these exo-planets,
planets outside our solar system, find themselves using
terms like Hot Jupiters and warm Neptunes.
Plus, there's a whole range of exo-planet sizes
from much smaller than Earth to even bigger than Jupiter.
To help describe what weight class each
of these planets belong to, we often refer back
to the different planet types in our solar system
using terms like Mini Neptunes
and Super-Earths or Super-Terrestrials.
We're constantly learning more about exo-planets
and our ideas about them are changing as we go,
ideas about how these different planet types relate
to each other and what their variety can teach us
about our own weird little solar system.