If Andromeda Galaxy were brighter, this is what we’d see

Andromeda Galaxy is the farthest object in the sky that we can see with the naked eye. But if you don’t know where to look, you won’t notice it. If it was much brighter, its appearance in the sky would be sensational. The moon is a good reference for what we’d see if our galaxy’s […]

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, […]

How Eratosthenes calculated the Earth’s circumference more than 2k years ago?

In 240 BC, the Greek astronomer, geographer, mathematician, music theorist, and librarian Eratosthenes of Cyrene (c. 276 BC – c. 195/194 BC) calculated the circumference of the Earth without even leaving Egypt. Here’s how:

Proxima Centauri b May Have Oceans

Proxima Centauri b, the Earth-like planet orbiting the red dwarf Proxima Centauri may have oceans, scientists say. The planet was discovered in August 2016 and caused excitement because it’s in the habitable zone of its star, and it’s rocky. And it’s in the Alpha Centauri, the closest star system to us! Researches of France’s National […]

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 […]

Proxima Centauri b: Did We Find Earth’s Cousin?

On August 24, 2016, a group of scientists led by Dr. Guillem Anglada-Escude at the Queen Mary University of London, announced the discovery of a terrestrial exoplanet orbiting the red dwarf Proxima Centauri, the nearest known star to the Sun. Proxima Centauri is a Latin idiom, meaning “nearest (star) of Centaurus” (see notes 1). The new […]

Where Earth’s water came from?

Earth is a blue marble in the space: the water, gives our planet its blue color: about 71 percent of the Earth’s surface is water-covered. There is roughly 326 million cubic miles (1.332 billion cubic kilometers) water on the Earth’s surface. Almost 97% of that water is salty (ocean water). But where all that water […]

Planet with Three Suns

On March 17, 1941, John W. Campbell, editor of Astounding Science Fiction, asked Isaac Asimov that: “What, if people see the stars once in a thousand of years?” Campbell has had read Ralph Waldo Emerson’s 1836 essay “Nature” and Emerson was saying in the first chapter that “If the stars should appear one night in […]