Elegant Earth
Alien worlds may be all the rage, with their mystique and promise, but the orb we call home, planet Earth, has all the makings for a jaw-dropping blockbuster movie: from the drama of explosive volcanoes, past meteor crashes and catastrophic collisions between rocky plates to the seeming fantasy of the ocean's deep abysses swirling with odd life and tales of the coldest, hottest, deepest, highest and all-out extreme spots. So try to stay grounded as you take a journey through some amazing facts about Earth.
Third Rock
Our home, Earth, is the third planet from the sun and the only world known to support an atmosphere with free oxygen, oceans of liquid water on the surface and — the big one — life.
Squashed Sphere
It's not a perfect sphere. As Earth spins, gravity points toward the center of our planet (assuming for explanation's sake that Earth is a perfect sphere), and a centrifugal force pushes outward. But since this gravity-opposing force acts perpendicular to the axis of Earth, and Earth's axis is tilted, centrifugal force at the equator is not exactly opposed to gravity. This imbalance adds up at the equator, where gravity pushes extra masses of water and earth into a bulge, or "spare tire" around our planet.
She's Got a Waistline
Mother Earth has a generous waistline: At the equator, the circumference of the globe is 24,901 miles (40,075 kilometers).
Hot Spot
The fiery award for Earth's hottest spot goes to El Azizia, Libya, where temperature records from weather stations reveal it hit 136 degrees Fahrenheit (57.8 degrees Celsius) on Setp. 13, 1922, according to NASA Earth Observatory. There have likely been hotter locations beyond the network of weather stations. (The image was created from data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite.
Pole Flip-Flops
In fact over the past 20 million years, our planet has settled into a pattern of a pole reversal about every 200,000 to 300,000 years; as of 2012, however, it has been more than twice that long since the last reversal. These reversals aren't split-second flips, and instead occur over hundreds or thousands of years. During this lengthy stint, the magnetic poles start to wander away from the region around the spin poles (the axis around which our planet spins), and eventually end up switched around, according to Cornell University astronomers.
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