Solar Eclipse Facts

Solar Eclipse

• The umbra is the full shadow that covers the sun during an eclipse.
• The penumbra is a partial eclipse view.
• If you're outside of the shadow, you won't see an eclipse.
• The moon is 400 times closer to Earth than the sun.

Moon and Earth

• The moon moves 3.8 cm away from Earth every year.
• The closest point of the moon's orbit to Earth is called perigee, and the farthest point is called apogee.

Gravity

• Gravity is a force of attraction that pulls objects together, but does not push them apart.
• Earth has a gravitational field around it.
• Gravity pulls objects with mass towards each other.
• The strength of gravity changes when objects move closer together or farther apart.

Meteors

• Gravity pulls chunks of rocks into the atmosphere towards Earth's center.
• As meteoroids enter the atmosphere, they get hotter and faster, creating a streak of light called a meteor.

Sun

• The radius of the sun is about 700,000 km, or about 110 times the radius of the Earth.
• The sun rotates differentially, faster at the equator and slower at the poles.

Atomic Structure

• An atom is the smallest piece of an element, and an element is made up of one type of atom.
• A molecule is the smallest piece of a compound, formed when two or more atoms chemically combine to form a new substance.
• Constituents of an atom include protons, neutrons, and electrons.

Sun's Power

• The surface temperature of the sun is 5780 degrees Celsius.
• Heat from the core reaches the surface of the sun through radiation and convection.

Surface Effects

• Granulation: areas of brighter and darker gas covering the sun's surface.
• Supergranules: larger, hotter areas of gas rising from under the surface.
• Sunspots: darker markings on the sun that usually appear in groups and last 1-100 days.
• Spicules: jets of gas ejected from the surface of the sun, found along the outline of a supergranule.
• Solar prominence: a loop of gas rising from the sun and then falling back.
• Solar flare: a huge burst of particles and energy shot out into space at speeds greater than the escape velocity.

Motion of the Sun

• The sun rotates on its axis about once per month.
• The gas on the surface rotates differently, faster near the equator and slower nearer to the poles.