Get total solar eclipse facts, including a list of upcoming total eclipses, the stages of the eclipse, and special features to see.
Astronomy
Learn how aurora colors work. See the chemistry and physics of the northern and southern lights and how the aurora works on other planets.
Aurora Colors Explained – Southern and Northern Lights
Learn what a solar eclipse is, how often one occurs, and how the different types of solar eclipses work. Get dates of upcoming ones.
What Is a Solar Eclipse? Recently updated !
Learn how many planets there are in the solar system and get their names. See why Pluto isn't considered to be a planet.
How Many Planets Are There in the Solar System?
Meet the dwarf planets in our solar system. Learn the dwarf planet definition and get a list of bodies that qualify.
Dwarf Planets in Our Solar System
Get facts about the Kuiper belt, including what it is, how far out it extends, and what bodies (Kuiper belt objects or KBOs) it contains.
Kuiper Belt – Objects, Location, Facts
Learn why the Sun and Moon are the same size in the sky and what it means for eclipses. See if it has always been this way.
Why the Sun and Moon Are the Same Size in ... Recently updated !
Learn what the shortest day of the year is in the Northern Hemisphere and Southern Hemisphere and how it relates to the solstice.
What Is the Shortest Day of the Year? Winter Solstice
Learn whether you can fit all the planets between the Earth and Moon. See the calculation that explains the answer.