How well do you think you know about our home planet?
Perhaps, you'll realise not that many after reading this short article.
1. The days are getting longer
The length of Earth's day is increasing. When Earth was formed 4.6 billion years ago, its day would have been roughly six hours long. By 620 million years ago, this had increased to 21.9 hours. Today, the average day is 24 hours long, but is increasing by about 1.7 milliseconds every century.
The reason? The moon is slowing down Earth's rotation through the tides that it helps create.
2. Earth isn't perfectly round
Earth has never been perfectly round.
Earth's diameter from North to South Pole is 12,714 kilometers, while through the equator it is 12,756 kilometers. The difference — 42.78 kilometers is about 1/300th the diameter of Earth.
This variation is too tiny to be seen in pictures of Earth from space, so the planet appears round to the human eye.
3. Driest place of earth
Ironically, the driest place in the world is next to the biggest body of water — the Pacific Ocean. the Atacama Desert in northern Chile has an Average annual rainfall of just 0.8 millimeters- SAHARA DESERT HAS 76 MILLIMETERS.
It is believed that Atacama's Calama city saw no rain for 400 years until a sudden storm fell in 1972. Unlike most deserts, the Atacama is relatively cold.
4. Our sun has an expiry date
All stars, like our sun, age and eventually die.
As the sun exhausts its supply of hydrogen, it will collapse under gravity, ultimately ballooning into a red giant that is 100 times bigger and 2,000 times more luminous, vaporizing Earth in the process. But don't worry; it won't happen for about five billion years.
5. Our earth is being stalked by 2 asteroids
Discovered in 1986, 3753 Cruithne is an asteroid that actually orbits the sun. Since it takes the same amount of time to orbit the sun as Earth, it looks as if Cruithne is following our planet. Its orbit, when seen from the perspective of Earth, appears bean-shaped.
Asteroid 2002 AA29 also orbits the sun once a year, following a more bizarre horseshoe-shaped path that brings it close to Earth every 95 years.
6. There weren't always several continents
Some 800 million years ago, the land is just 1 huge continent called rodinia. it broke apart, and 250 million years ago, the continents came together once again to form another supercontinent called Pangaea.
Fifty million years later, Pangaea began to break apart. It split into two large land masses — Gondwanaland and Laurasia — that ultimately fragmented into the continents we know today.