Terminator
the border between light and dark on the Moon
Moon
a rocky sphere that travels around a planet
New Moon
a moon phase in which the Moon is not visible from Earth
the sun, the planets that orbit the sun, and other objects that orbit the sun
Exomoon
a moon outside our solar system
Lunar Eclipse
when the Moon is completely dark
Gravity
a force that pulls matter closer together
Scale
the relative size of things
Model
an object, diagram, or computer program that helps us understand something by making it simpler or easier to see
Full Moon
a moon phase that looks like a full circle from Earth
Pattern
something we observe to be similar over and over again
Moon Phase
the shape of the illuminated part of the Moon as it appears from Earth
Orbit
the nearly circular path a smaller object travels around a larger object
Illuminate
to shine light on an object and make it visible
Year
the amount of time it takes for a planet to complete one orbit around a star or stars
Exoplanet
a planet outside our solar system
Crescent Moon
a moon phase that looks like less than half a circle from Earth
Sun
the star that is the main source of light at the center of our solar system
Gibbous Moon
a moon phase that looks like more than half a circle from Earth
Quarter Moon
a moon phase that looks like a half-circle from Earth