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* Earth is currently the only known planet to support any form of confirmed life.
* The friction created by our only Moon’s pull on the tides of our oceans is causing the Earth to very gradually slow down. In turn, as the Earth slows down its rotation, it slowly lets the Moon creep ever so slightly further away.
* Our atmosphere is composed of 77% nitrogen, 21% oxygen, as well as trace amounts of water, carbon dioxide, and argon.
* These trace amounts of carbon dioxide as well as water vapor continuing to circulate in the atmosphere provide a greenhouse gas effect.
*  This greenhouse gas effect sustains the average temperature of the Earth to a degree in which is currently aids in sustaining life on the planet and keeping the oceans from freezing.
* Unlike the other three terrestrial planets in the solar system, Earth’s crust is divided into “tectonic plates,” or separate plates which float independently on top of the much hotter mantle that sits below them.
* There are seven primary tectonic plates and several smaller ones, and the majority of earthquake and volcanic activity on the planet occurs in places where tectonic plates meet, particularly in the Pacific Ring of Fire. There are three major types of tectonic plate activity:
    - Divergent - the plates move apart from one another
    - Subduction - an oceanic plate moves under a continental plate; this usually causes the most violent earthquakes and volcanic activity
    - Transform - plates slide back and forth against one another
* As a result of this plate activity, the physical structure of Earth has changed remarkably since its formation.
* For example, approximately 300 million years ago, our planet had only one continental body we now call Pangaea. About 200 million years ago, that continent began to split apart and form our current seven continents. Even now, these continents are not stationary, and are continuing to move as tectonic plates shift.
* Over 71% of Earth is covered in water.
* It is the only planet in the solar system known to be able to sustain liquid water, although some may one day be found on Jupiter’s moon Europa.
* 97% of the water on the planet is salt water, 2% is glacier ice at both of the poles, and less than 1% is fresh water.
* Oceanographers estimate that we have only explored approximately 5% of of Earth’s oceans, and some claim that we have more detailed maps of Mars and its surface than we do of our own oceans