World's Smallest Mammal

On the end of other spectrum, there are plenty of teeny-tiny organisms on Earth that are not discovered yet, all the way down to single-cell life. But let us focus on something that is little more cuddly: the Kitti's hog-nosed bat. This vulnerable species is found in the southeast Asia is only about 1 inch (29-33 millimeters) long weighing 0.071 ounces (2 grams), putting it in the running with Etruscan shrews, which are lighter but longer, for the world's smallest mammal.

Aurora Borealis

Auroras occur when charged particles from the sun are funneled toward Earth by the planet's magnetic field and collide with the upper atmosphere near the poles. They are more active when the sun's activity peaks during its 11-year solar weather cycle.

The southern lights, also called aurora australis, are seen less often than aurora borealis, the northern lights, because few people brave Antarctica's dark, freezing winters. Shown here, a 2008 image taken from Antarctica of the dazzling sky lights. 

Largest Earthquake

As of 2011, the largest earthquake to shake the United States was a magnitude-9.2 temblor that struck Prince William Sound, Alaska, on Good Friday, March 28, 1964. (Photos shows the Four Seasons Apartments in Anchorage, a six-story lift-slab reinforced concrete building, which cracked to the ground during the quake.) And the world's largest earthquake was a magnitude 9.5 in Chile on May 22, 1960, according to the U.S. Geological Survey (USGS).

Our Moon Quakes!

Moonquakes, also known as "earthquakes" on the moon, do occur, though they are less common and less intense than the one who shakes Earth. According to USGS scientists, moonquakes seem to be related to tidal stresses associated with the varying distance between Earth and moon. Moonquakes also tend to occur at great depths, about midway between the lunar surface and its center.

It was Recycled !

The ground you're walking on is recycled. Earth's rock cycle transforms igneous rocks to sedimentary rocks to metamorphic rocks and then back again. The cycle is not a perfect circle, but the basic works like this: Magma from deep in the Earth emerges and hardens into rock (that's the igneous part). Tectonic processes uplift that rock to the surface, where erosion shaves bits off. These tiny fragments gets deposited and buried, and the pressure from above compacts them into sedimentary rocks such as sandstone. If sedimentary rocks get buried even deeper, they "cook" into metamorphic rocks under lots of pressure and heat. Along the way, sedimentary rocks can be re-eroded or metamorphic rocks re-uplifted. But if metamorphic rocks get caught in a subduction zone where one piece of crust is pushing under another, they may find themselves transformed back into magma.

It is OLD !

The researchers calculate the age of the Earth by dating both the oldest rocks on the planet and meteorites that have been discovered on Earth (meteorites and Earth formed at the same time, when the solar system was forming). They say that the Earth is about 4.54 billion years old.

On The Move!

You can feel like you are still standing, but you were actually moving — fast. It depends on where you are on the globe, you could be spinning through space at over 1,000 miles an hour. People on the part of equator move the fastest, while the one whi is standing on the North or South pole would be perfectly still. (Imagine a basketball spinning on your finger. A random point on the ball's equator has farther to go in a single spin as a point near your finger. Thus, the point on the equator is moving faster.)