The Universe
This theory explains how the universe began about 13.8 billion years ago.
What is the Big Bang Theory?
This theory says the Sun is at the center of the solar system.
What is the heliocentric theory?
The name of Earth’s moon.
This force pulls objects toward each other and helped form galaxies and solar systems.
What is gravity?
The day with the longest daylight in the Northern Hemisphere.
What is the Summer Solstice?
These huge collections of stars, gas, and dust come in shapes like spiral, elliptical, and irregular.
What are galaxies?
This theory says Earth is at the center of the universe.
What is the geocentric theory?
Between a new moon and a full moon, the moon is doing this.
What is waxing?
The path an object takes as it moves around another object.
What is an orbit?
The day with the shortest daylight in the Northern Hemisphere.
What is the winter solstice?
This is the name of the galaxy we live in.
What is the Milky Way Galaxy?
These planets are small, rocky, and closest to the Sun.
What are terrestrial planets?
These are the changing shapes of the moon we see from Earth.
What are the phases of the moon?
This force keeps objects moving in a straight line unless acted on by another force.
What is inertia?
These two days have equal amounts of daylight and darkness. Half way points between the two solstices.
What are the equinox of spring or autumn?
A unit of distance equal to how far light travels in one year.
What is a light year?
This belt separates the inner planets from the outer gas giants.
What is the asteroid belt?
A chunk of rock in space is a meteoroid. When it enters Earth’s atmosphere it becomes a meteor. If it hits the ground, it becomes this.
What is a meteorite?
When the shape of a comet’s orbit varies, this is described as this.
What is eccentric?
This process powers the Sun by fusing hydrogen atoms into helium.
What is nuclear fusion?
A region in space where gravity is so strong that not even light can escape.
What is a black hole?
This dwarf planet was once considered the ninth planet.
What is Pluto?
A solar eclipse is only visible to a small part of Earth because this shadow is very narrow.
What is the Moon’s umbra?
The glowing cloud of gas around a comet’s nucleus.
Energy from the Sun travels through space in this form.
What are electromagnetic waves?