Solar Eclipse Facts

Study Notes

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.

Description

Test your knowledge about solar eclipses, the moon's orbit, and how astronomers like Hipparchus, Newton, and Einstein used eclipses to prove their theories. Learn about the umbra, penumbra, and how the moon's distance from Earth affects our view of the sun.