Galaxy and Planet

Do you know what is the horizon?

The horizon or skyline is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth’s surface, and those that do not. What is the [ … ]

What everybody ought to know about galaxies!

A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.   What are galaxies? The word galaxy is derived from the Greek galaxias, literally “milky”, a reference to the Milky Way. Galaxies range in size [ … ]