Make a model comet with dry ice and without. See how the model simulates a real comet and illustrates its parts.
Astronomy
See how to choose a telescope. Learn the difference between reflectors vs refractors, types of mounts, and other factors you should consider.
How to Choose a Telescope – Reflector vs Refractor
Learn what right ascension and declination mean (RA and DEC) and how to use them to find stars, planets, and other celestial objects.
Right Ascension and Declination
Learn where the atmosphere ends and space begins. See why it's difficult to set a single value for where outer space starts.
Where Does Space Begin? The Kármán Line
Learn what the zodiacal light is. Find out what it looks like. Determine the best time and location to see it.
What Is the Zodiacal Light? When and How to See ...
Learn the difference between meteoroids, meteors, meteorites, comets, and asteroids.
Difference Between Meteoroids, Meteors, Meteorites, Comets, and Asteroids
Find out which element is the most abundant element in the universe. See the abundance of other elements, too.
What Is the Most Abundant Element in the Universe?
One easy way to calculate your weight on other planets is to multiply your weight on Earth by the ratio between gravity on another planet and Earth.
How to Calculate Weight on Other Planets
The moon rotates, completing one rotation each month so we only see one side.