Celestial Sphere
History of Astronomy
Laws of Nature
Light and Telescopes
Terrestrial Planets
100

A collection of millions or billions of stars, bounded together by gravity.

What is a galaxy?

100

This historic figure developed three laws which describe the motion of the planets.

Who is Johannes Kepler?

100

A law that describes how the net force of an object equals the object's mass multiplied by its acceleration. 

What is Newton's Second Law?

100

To our eyes, hotter objects appear more like this color.

What is blue?

100

The source of materials that become the building blocks for planets.

What is a nebula?

200

The Earth's 23.5 degree axial tilt is the angle between Earth's rotation axis and ________.

What is the ecliptic plane?

200

A model designed to explain what we see in the night sky while having the Earth orbit the Sun.

What is the heliocentric model?

200

A measurable property of an object that does not change over time.

What is a conserved quantity?

200

The spectra of most galaxies show redshifts, meaning that their spectral lines have wavelengths that are ________ than normal.

What is longer?

200

The region of the Solar System where Ceres is found.

What is the Asteroid Belt?

300

A star that always lies above your local horizon.

What is a circumpolar star?

300

A model based on natural processes whose predictions explain a wide variety of observed phenomenon.

What is a scientific theory?

300

________ are responsible for the Moon always showing the same face to the Earth.

What are tides?

300

We put some telescopes into space because some wavelengths are completely absorbed by the Earth's ________.

What is atmosphere?

300

Smaller bodies lose heat faster because they have a relatively large ________ compared to their volume.

What is surface area?

400

The season experienced in the Southern Hemisphere when the Northern Hemisphere is tilted towards the Sun.

What is winter?

400

For most of history, the lack of observable stellar ________ was interpreted to mean that the Earth was stationary at the center of the Universe.

What is parallax?

400

An object in an orbit that is ________ around the Sun means that it will approach the Sun once and then never return.

What is unbound?

400

We observe this type of spectrum when we look at a star with an intervening cloud of cool gas.

What is an absorption spectrum?

400

Planets emit most of their light in this wavelength range.

What is infrared light?
500

A New Moon rises approximately at this time of day.

What is sunrise?

500

The great contribution of ________ was to create a detailed model of our Solar System with the Sun at the center.

Who is Nicolaus Copernicus?

500

Earth is farthest from the Sun in July and closest to the Sun in January, meaning that Earth moves slowest in the Northern Hemisphere's season of ________.

What is Summer?

500

This property of a telescope provides it with more light collecting area and a better angular resolution.

What is diameter?

500

This feature on Earth plays a key role in the CO2 cycle by allowing for the storage of CO2 within the Earth's mantle.

What are plate tectonics?

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