The Dolphin Nebula is a planetary nebula in the constellation Cassiopeia, it lies an estimated distance of 5,200 light years away from Earth.

Everyone has heard of the electromagnetic spectrum. It is a collection of all wavelengths and frequencies of light, from radio and microwave to ultraviolet and gamma. The light we see is called the "visible" part of the spectrum. The rest...

Galaxies can be classified into three main types: elliptical, spiral, and irregular. Hubble's morphological classification is a more detailed taxonomic method. Since the Hubble method classifies galaxies only on the basis of shape, it ignores the rate of star formation...