GALAXY 
MARS 
NEBULAE AND STAR CLUSTERS 
THE MILKY WAY 
STAR 
GALAXY
A GALAXY IS A HUGE MASS OF STARS, nebulae, and interstellar material. The smallest galaxies contain about 100,000 stars, while the...
MARS
MARS, KNOWN AS THE RED PLANET, is the fourth planet from the Sun and the outermost rocky planet. In the 19th...
NEBULAE AND STAR CLUSTERS
A NEBULA IS A CLOUD OF DUST AND GAS inside a galaxy. Nebulae become visible if the gas glows, or if the...
THE MILKY WAY
THE MILKY WAY IS THE NAME GIVEN TO THE FAINT BAND OF LIGHT that stretches across the night sky. This light...
STAR
STAR as an astronomical object consisting of a luminous spheroid of plasma held together by its own gravity. The...
ASTEROIDS, COMETS, AND METEOROIDS
ASTEROIDS, COMETS, AND METEOROIDS are all debris remaining from the nebula from which the solar system formed 4.6 billion years ago....
