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 […]

Yet Another Scale Model of the Solar System (video)

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 really large numbers, these articles provide amazing ways to understand how big […]

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 […]

The Size Of Earth Compared to Other Planets and Stars (and the Universe)

Have you ever wondered how big is the Earth compared to other planets? Or other stars? Or even the Universe itself? When it comes to big numbers, very big numbers, the human brain is weak. In fact, our brains cannot deal with really large numbers. That’s why when the subject is Earth, planets, Solar System, […]

The scale of the Solar System and the first flybys of planets

Previously I posted two 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 an amazing way to […]

Planet Nine – Where is it?

In January 2015, Caltech (California Institute of Technology) astronomers Konstantin Batygin and Michael E. Brown published an article titled Evidence For A Distant Giant Planet In The Solar System and announced calculation-based evidence of a massive ninth planet. Despite they have had started their research to demonstrate that there’s no ninth planet, they reached the […]