Galaxy and Planet

Pluto in the Kuiper belt in the Solar System

The Kuiper belt, sometimes called the Edgeworth–Kuiper belt, is a circumstellar disc in the Solar System beyond the (known) planets, extending from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun.   What is the Kuiper belt? It is [ … ]

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 [ … ]