Explore Earth
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Earth, the largest and densest rocky planet, was formed about 4.5 billion years ago. The Earth's ...
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The atmosphere is a mixture of nitrogen (78%), oxygen (21%), and other gases (1%) that surrounds ...
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The Earth has a magnetic field with north and south poles. The magnetic field of the Earth ...
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The Earth's one natural satellite, the Moon, is more than one quarter the size of Earth itself ...
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Do you wonder what Earth's Polar Regions are like? Where do polar bears live? Where do penguins ...
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Warm near the equator and cold at the poles, our planet is able to support a variety of living ...
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Water is found in many places on Earth including on the surface of the planet, within rocks ...
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What is life? Why is there life on Earth, but not on any other planets in the solar system ...
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The United Nations estimated that between 1994-2015, there were 6,873 natural disasters worldwide, ...
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Did you know?
Did you know that Earth is the
largest and densest rocky planet in the solar system?
Did you know that many different
cultures had myths
about Earth goddesses and gods?
Earth and Space Science Concept of the Day
Do you know what this word or phrase means?
Magnetic polarity reversalxMagnetic polarity reversal : A magnetic polarity reversal is a change of the earth's magnetic field to the opposite polarity. This has occurred at irregular intervals during geologic time.
Click on the word to find out!
Research Highlights
Marine scientists long believed that a microbe called Trichodesmium, a member of a group called the cyanobacteria, reigned over the ocean's nitrogen budget. New research results reported on-line today...
Read more![](/olpa/images/microbe1_sm.jpg)