Planetary confusion: why astronomers keep changing what it means to be a planet

Christopher Palma, Pennsylvania State University As an astronomer, the question I hear the most is why isn’t Pluto a planet anymore? More than 10 years ago, astronomers famously voted to change Pluto’s classification. But the question still comes up.

Solar System through the eyes of Hubble Space Telescope

Hubble Space Telescope was launched on April 24, 1990, and entered service on May 20, 1990. Since then, it has observed all the planets in our Solar System, apart from Earth and Mercury. Earth is far better studied by geologists on the ground and specialized probes in orbit. Hubble can’t observe Mercury as it is […]

Top 10 Largest Non-Planets In Our Solar System

There are eight planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Two of the largest moons are bigger than the smallest planet, Mercury. Here are the top 10 largest non-planets in our solar system (eight of them are moons and two of them are dwarf planets).

Watch: Yet Another Scale Model of the Solar System

Previously I posted articles titled “If The Moon Were Only 1 Pixel – A Tediously Accurate Map Of The Solar System” and “A Scale Model Of Solar System Drawn In The Desert And The Result Is Stunning”. Since the human brain cannot deal with the really large numbers, these articles provide amazing ways to understand how […]

Size comparison of the Sun and the planets

This size comparison of the Sun and the planets in our solar system is going around frequently, but it’s still amazing to see it. Created by the San Francisco-based artist Roberto Ziche, the image features the Sun in the background with the planets, Moon and the four dwarf planets lined up in the foreground in the […]