Blue Marble: the famous Apollo 17 photograph of Earth from space

On December 7, 1972, the crewmembers of Apollo 17 spacecraft en route to the Moon took a photo of Earth from space, at a distance of about 45,000 kilometers (28,000 miles). This image, with the official NASA designation AS17-148-22727, became known as “The Blue Marble”. It remains one of the most iconic photos of Earth …

Perućica, one of the last remaining primeval forests in Europe

Located in Republika Srpska, Bosnia and Herzegovina, Perućica is one of the last two saved primeval forests in Europe (the other being the Białowieża Forest). Perućica has many trees that are 300 years old, and its age is stated to be 20,000 years (it existed even before the last Ice Age which concluded about 11,550 …

When did we first realize that Saturn had rings

Before the invention of the telescope, no one on Earth knew that Saturn had rings until the 1600s. Galileo Galilei discovered them with his telescope in 1610, but he did not know what these were either. Thus they remained a mystery until 1655 when the Dutch astronomer Christiaan Huygens (see notes 1) figured out that they …

10 Amazing Great White Shark Facts

The great white shark (scientific name: Carcharodon carcharias) is one of the most feared beasts in the world’s oceans. They are also known as simply the “great white”, white pointer, white shark, or white death. They can be found in the coastal surface waters of all the Earth’s oceans. Here are 10 amazing great white …

How Mars Died? The Death Of Mars

Mars is now a cold and extremely arid desert that is constantly bombarded with deadly solar radiation. It has a very thin atmosphere (it’s really thin, it is practically almost a vacuum) and no liquid water. But that was not always the case. Billions of years ago, Mars had liquid water on its surface. It …

Why do leaves change color in the fall?

Plants are green because their cells contain chlorophyll (a green pigment, see notes 1) inside little structures called chloroplasts. Chlorophyll is green because it absorbs other wavelengths of light, but reflects the wavelength that we see as green. That’s why most plants are green, including trees and grass. Those wavelengths that the chlorophyll is absorbing? …

The largest island-in-a-lake-on-an-island-in-a-lake-on-an-island in the world

There’s an island within a lake that is situated on an island located in a lake on an island in the Philippines called Vulcan Points. But, it’s not the largest such island. Vulcan Points is about 50×80 meters in size (about 164×262 feet). “The largest island-in-a-lake-on-an-island-in-a-lake-on-an-island in the world ” title belongs to an island …