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. But if it were much brighter, its appearance in the sky would be sensational. The moon is a good reference about what we’d see in the […]

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

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, galaxies, and in general, the Universe, we cannot truly conceptualize the things. A lot of people think we’re “conquering” space (we […]

How Eratosthenes calculated the Earth’s circumference

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: Eratosthenes knew that at local noon on the summer solstice (at the time of the longest day, about 21 June in […]

How Mars would look if it still had water

What if Mars still had liquid water on its surface and a thick atmosphere filled with clouds, like Earth? How would it look like? Software engineer Kevin Gill of JPL (NASA’s Jet Propulsion Laboratory) wondered this and prepared an image using data from NASA’s Mars Reconnaissance Orbiter (MRO)(1) and Mars Orbiter Laser Altimeter (MOLA)(2). The […]

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 […]

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” (1). The new planet is […]

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 […]