Definition: Relating to the point in the orbit of the moon or a satellite at which it is closest to the Earth.

Example: The perigean tide occurs when the moon is closest to the Earth, resulting in higher than normal tides.

Definition: The closest point in the orbit of an object around a planet or moon.

Example: The satellite reached its perigee just before it began to ascend again.

Definition: The location in a planet's or other celestial body's orbit where it is closest to the sun.

Example: Earth reaches its perihelion in early January each year.

Definition: The point in an orbit around the Moon where the orbiting object is closest to the Moon.

Example: The spacecraft reached perilune just before beginning its descent to the lunar surface.

Definition: The outer layer of a star that gives off light, particularly the sun.

Example: The photosphere of the sun is where sunspots can be observed.

Definition: Relating to the visible surface of a star, especially the sun, where light is emitted.

Example: The photospheric temperature of the sun is about 5,500 degrees Celsius.

Definition: A large celestial object that orbits a star, has enough mass to be round, and is not a moon of another object.

Example: Earth is the third planet from the sun in our solar system.

Definition: A place or building where people can watch shows about stars, planets, and other space objects, often using a special dome-shaped screen.

Example: We visited the planetarium to learn more about the universe and see a show about the stars.

Definition: Relating to or resembling planets, or affecting the whole world.

Example: The scientists studied the planetary movements to understand the solar system better.

Definition: Having characteristics or qualities similar to a planet.

Example: The newly discovered celestial body has a planetlike atmosphere that could support life.