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Where are we in the solar system? -

The Earth is the third planet from the Sun. It's one of four terrestrial planets. Like Mercury, Venus, and Mars, it has a hard, rocky surface.

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Earth's atmosphere -

Our home is coated with many layers of atmosphere, including the mesosphere, ionosphere, exosphere, and the stratosphere. But it's the troposphere, closest to the planet itself, that supports our lives. This layer contains most of Earth's clouds and is the location where weather primarily occurs.

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Not a perfect sphere -

Earth has never been completely round. It's not a perfect sphere. This is because the planet bulges around the equator due to the fact that it rotates about its axis. More worryingly, NASA suggests that melting glaciers are causing Earth's waistline to spread.

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Putting a spin on it -

We are constantly moving on Earth, even when we're standing still. The planet spins at roughly 1,000 miles (over 1,600 km) per hour. That's an astonishing 460 meters (over 1,500 feet) per second.

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Long days ahead -

According to NASA, the days are getting longer. This is because the Moon is imperceptibly drifting away from Earth. This slows down our planet's rotation through the tides that it helps create. As a result, our days are being extended.

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How old is the Earth? -

The Earth is about 4.54 billion years old. Scientists know this by dating both the oldest rocks on the planet and meteorites that have been discovered on Earth, both of which were formed at the same time, when the solar system was forming.

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When continents collide -

About 250 million years ago the continents came together to form a supercontinent called Pangaea, surrounded by a vast ocean. Fifty million years later, Pangaea began to break apart. This resulted in two new land masses—Gondwanaland and Laurasia. These eventually fragmented into the continents we know today.

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Salt of the Earth -

If all the ocean water evaporated, there would be enough salt to cover the entire surface of the Earth. More precisely, spread evenly over the planet's land surface, it would form a layer more than 500 feet (166 meters) thick.

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Largest inland sea -

The largest inland sea (often described as the world's largest lake) is the Caspian Sea. It covers a surface area of 143,000 sq mi (371,000 km2).

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Driest place on Earth -

The Atacama Desert is the driest nonpolar desert in the world. Located in Arica, Chile, average annual rainfall is just 0.03 inches (0.8 millimeters).

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Coldest place of Earth -

It's no surprise that Antarctica is the coldest place on Earth. Winter temperatures, fueled by wind chill, can drop to a bone-chilling -100°F (-73°C).

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Natural holding tank -

Remaining in the south, the Antarctic ice cap holds around 70% of Earth's fresh water and roughly 90% of its ice. This is despite the fact that it's only the world's fifth largest continent.

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Get the drop on Earth's gravity -

Earth's gravity isn't uniform. It varies geographically. For example, gravity is stronger in the Himalayas than it would be on a perfectly flat, featureless planet. These variations are known as gravity anomalies. In other words, areas with higher subsurface rock density have higher than average, or positive anomaly, gravity. Conversely, ocean trenches decrease it—a negative gravity anomaly.

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Sea level fluctuation -

Global sea levels have fluctuated significantly over Earth's history. This has a lot to do with the advance of ice on the planet about 70,000 years ago, and which ended about 11,500 years ago. So much water was trapped as ice that sea levels dropped by as much as 390 feet (120 meters). The current sea level is about 426 feet (130 meters) higher than the historic minimum. Global warming is set to increase it further.

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Shifting of the magnetic North Pole -

Unlike the geographic North Pole, which is stationary, the magnetic North Pole moves about 10 to 15 km (about 6 to 9 miles) northwest per year. This movement is probably explained by a fluctuation in the strength and orientation of the magnetic field.

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End of the world as we know it? -

Earth is set to be vaporized. But don't worry: this cataclysmic event will not take place for five billion years. But it will happen when the Sun exhausts its supply of hydrogen, causing it to collapse under gravity. It will then balloon in size, becoming 2,000 times more luminous and turning into giant, deadly ray gun.

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Hottest place on Earth -

Death Valley in California is the hottest place on Earth. On July 10, 1913, the highest temperature ever recorded was registered at Furnace Creek Ranch, when the mercury topped 134°F (56.7°C). In the scorching summer of 2023, Death Valley hit 129°F (53°C).

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Two moon scenario -

Earth may have once had two moons, but the smaller one was apparently destroyed in a slow-motion collision. Scientists account for this by the fact that our existing natural satellite is bumpier one side than the other, suggesting a titanic clash billions of years ago.

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Cosmic dust -

Experts from the United States Geological Survey claim that around 1,000 tons of space debris rains down on our planet every year. Furthermore, data published by the European Space Agency from December 2023 showed that almost 2,500 bits of space debris fell to Earth the year before.

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Longest mountain range on Earth -

The Mid-Atlantic Ridge system that bisects the North and South Atlantic basins is the longest mountain range on Earth, reaching approximately 40,000 miles (65,000 km).

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Plate tectonics -

Simply put, plate tectonics describes the large slabs of rock that divide Earth's crust, and move constantly to reshape the Earth's global landforms and environments.

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Electrical storms -

In an impressive display of power, a single stroke of lightning can heat the air to around 54,000°F (30,000°C). The accompanying thunder is a result of the ballooning air creating a shock wave and ultimately a boom.

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Earth's largest living structure - Coral reefs are the largest living structures on Earth, a community of connected organisms made up of tiny coral polyps.

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Deepest point on Earth -

The deepest point on the ocean floor is located in the Western Pacific 36,200 feet (11,033 meters) below sea level in the Mariana Trench.

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Deadly lakes -

Lake Nyos (pictured) and Lake Monoun, both in Cameroon, plus Lake Kivu in the Democratic Republic of Congo are the world's deadliest lakes. Each contain a massive amount of carbon dioxide in their depths. In 1984, a limnic eruption at Monoun released this deadly gas, killing 37 people. In 1986, Nyos suffered the same fate. Then, 1,746 people and 3,500 livestock perished. Meanwhile, inhabitants of the Kivu region are holding their breath in the hopes their lake doesn't follow suit.

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Purple haze -

Some scientists have speculated that the Earth might have once been purple as it is green today. Ancient life forms may have been able to generate metabolic energy from sunlight using a purple-pigmented molecule called retinal, according to NASA Astrobiology.

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Core values -

At 1.516 miles (2,440 km) across, the Earth's core is almost the size of the Moon. It also makes up roughly  19% of Earth's total volume.

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Safety first -

The Earth's core plays a significant role in keeping us safe. It is responsible for the generation of Earth's magnetic field, which in turn interacts with the interplanetary magnetic field produced by the Sun. This interaction creates the magnetosphere, which serves as a protective field against solar winds.

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Alien Earth -

Scientist have found evidence of other Earth-like planets that could sustain life. Kepler 22-b, for example, lies in what's known as a habitable zone where water could exist in liquid form on the planet's surface. This diagram compares our own solar system to Kepler 22-b.

Sources: (Live Science) (National Science Foundation) (National Geographic) (ScienceDirect) (NASA Astrobiology)

See also: Discover 60 extreme points of Earth

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