Seasons & Sunlight
Kepler & Orbits
Stellar Evolution
Cosmology & Redshift
"Houston, we have a question!"
200

The reason Earth has seasons

Tilt

200

Name for the oval shape that describes a planet's path around the Sun.

Ellipse

200

The original stage all stars begin as, and what determines their future path.

Cloud of dust and gas

200

The current scientific model for how the universe started.

Big Bang Model
200

Even in a galaxy full of stars, this number lets each atom stand out in the element-ary school yearbook

Number of protons

400

This term describes the two times of the year when nighttime and daytime are the came length.

Equinox

400

The position in a planet's orbit when it is farthest from the Sun.

Aphelion

400

When a star is stable in size, its because these two forces are balanced.

Fusion & gravity

400

This observed phenomenon how we know the universe is expanding.

Redshift

400

This cosmic unit helps us measure distances between stars — because ‘a bazillion kilometers’ isn’t scientific enough.

Light years

600
This Kepler's Law explains why planets speed up when closer to the Sun

Kepler's 2nd Law or "Equal Areas in Equal Times"

600

At the end of its life, our Sun (a main sequence star) will be in this stage.

Black dwarf

600

They’re dense, rocky, and keep things down to Earth — unlike those giant gasbags hanging out past the asteroid belt.

Terrestrial planets or Inner planets

800

You would find this angle of sunlight happening during the winter in Iowa

Low angle

800

The Kepler's Law that says planets farther from the Sun take longer to orbit.

Kepler's 3rd Law or p2 = a3

800

The powerful explosion that ends a high-mass star’s life and can create any element on the periodic table

Supernova

800

If stars had dating profiles, this trait would tell you who’s cool, who’s hot, and who’s just a red giant pretending they still got it.

Color

1000

The two places during stellar evolution where the whole process can start over from the beginning

Planetary nebula & supernova

1000

What happens to the speed of a star/galaxy as it gets farther away

Speeds up

1000

This spectral stretching doesn’t involve yoga — but it does tell us when galaxies are moving away and taking their light with them.

Redshift