Use the links next to the caption "Cool Facts" to view past cool facts.

These are the facts you could find on this page:
Active Languages, Blood-Free Tissue, Closest Orbiting Moon, Cold Volcanoes, Fastest Humans, Fastest Waves, Footbag Origins, Meteor Showers, Micro-graffiti, Seafood Fertilizer

Active Languages
According to recent estimates, the number of actively spoken languages in the world today is around 6,000. More than 1,400 of those languages belong to the Niger-Congo family from Africa, and about 1,200 are in the Austronesian family from Madagascar, Indonesia, Australia, the Pacific Islands, and New Zealand.
Most of today's active languages are spoken by very few people, and many of them are losing speakers rapidly as the world becomes more and more connected. Half of today's languages have fewer than 10,000 speakers, and a quarter have fewer than 1,000.
Thousands of years ago, there may have been as many as 10,000 active languages in the world. Within the next century, thousands of languages may be lost.
Back to Top

Blood-Free Tissue
The only living tissue in the human body that contains no blood vessels is the transparent cornea of the eye. It's the firm, smooth outer shell that arcs across in front of the iris and pupil.
The cornea contains no blood vessels because it must be perfectly clear. Even one tiny capillary would cast the shadow of hundreds of streaming blood cells into the light coming through the pupil.
Without blood to provide oxygen and nutrients, the cornea must get them from somewhere else. Nutrients come from the tears and from the liquid (aqueous humor) that fills the chamber behind the cornea. Oxygen is no problem, since the cornea is in direct contact with the air.
Back to Top

Closest Orbiting Moon
Of all the moons in the solar system, the one with the closest orbit is Phobos, the larger of the two satellites of Mars. The orbit of Phobos is less than 6000 kilometers above the surface of the planet (3700 miles).
Phobos is an irregularly shaped chunk of rock and ice about 27 kilometers long (17 miles). Because its orbit is so low, it can only be seen from a limited strip of the planet near its orbital path. Seen from that strip, it crosses the sky quickly from west to east, twice a day.
Phobos' orbit is so low that tidal forces are pulling it closer and closer to Mars. Scientists expect that in about 50 million years it will either crash into the planet or break up into a thin ring of orbiting debris.
Back to Top

Cold Volcanoes
Neptune's moon Triton is the coldest place in the solar system, with a surface temperature of -235 degrees Celsius (-390 degrees Fahrenheit). As cold as it is, there are active volcanoes on Triton in which the erupting liquid is frigidly cold liquid nitrogen.
At Triton's surface, nitrogen normally exists as frozen ice. But under the surface, where Triton is heated by slow radioactive decay of its rocks, nitrogen melts into a liquid. When the liquid heats up still further, it boils and erupts through the surface, spewing evaporating liquid nitrogen high into space.
Back to Top

Fastest Humans
Relative to the planet Earth, the fastest speed humans have achieved was 24,791 miles per hour (39,914 km/hr), by the Apollo 10 astronauts, on their return trip from the moon in 1969.
But the universe is much bigger than the Earth-Moon system, and everything moves. If the Sun is taken as a fixed point, then all the humans on Earth are moving at about 66,660 miles per hour (107,320 km/hr) as the Earth follows its orbit.
If the center of the Milky Way galaxy is a fixed point, then the solar system is moving at about 500,000 miles per hour (800,000 km/hr) in its orbit around the galaxy.
From an even broader reference frame, our entire local group of galaxies is moving at about one million miles per hour toward another galaxy group called Virgo Cluster.
Back to Top

Fastest Waves
The fastest ocean waves are also the rarest and the most dangerous. They are tsunamis, very long waves that move across the open sea at speeds approaching 500 miles per hour (800 kph).
A tsunami (sometimes incorrectly called a "tidal wave") is caused by a geological event like an earthquake, underwater landslide, or volcanic eruption. As it moves across the open sea it is only a few feet high, although it may be more than 100 miles long (160 kilometers). Ships do not notice its passage.
But when it reaches the shore, interaction with the bottom slows the wave down and all its energy is concentrated at the surface. A wall of water quickly builds up that can be as high as a multi-story building.
Back to Top

Footbag Origins
The sport of footbag has been played for centuries by Asians and Native Americans, who used small, soft bags filled with nuts or pebbles. But it did not take off in the modern world until 1972, when a football player named John Stallberger made it into a popular hit.
Stallberger was recovering from a knee injury. His friend Mike Marshall suggested that he keep his legs flexible during his recovery by kicking around a small bag. They called it "hacking the sack."
Stallberger and Marshall began marketing their "hacky sacks" and were immediately successful. Today, footbag is an international sport with champions and competitive rules.
Note: Hacky Sack is a trademark of Wham-O, Inc.
Back to Top

Meteor Showers
Most meteors are tiny flecks of cosmic dust that strike the Earth's atmosphere in random directions. But there are also collections of dust and grains of rock (meteoroids) that orbit in streams around the Sun. When the Earth's orbit crosses one of these streams, we might have a sudden meteor shower.
Meteoroid streams form along the orbits of comets, which release dust and debris as the Sun evaporates their ices. Some of them repeat every year at the same time. These are named according to the constellation from which the meteors appear to originate (the radiant of the swarm). We have the Leonids from Leo, the Orionids from Orion, and many others.
The most intense meteor showers are spectacular meteor storms, where dozens or even hundreds of meteors flash across the sky every minute.
Back to Top

Micro-graffiti
If you have any electronic device that contains microchips, you may own some chip graffiti, the smallest form of public art.
For many years, chip designers have placed tiny, embossed drawings in unused spots on integrated circuit chips. The drawings are made out of the same silicon and other materials that form the circuits. The art is dying out because most chip designs these days are created by automatic software, but many devices still contain older chips that hold the drawings.
There is great variety among the designs, which include human figures, animals, buildings, vehicles, appliances, comic strip characters, and cultural icons like "Mr. T," the "happy face" and Pac Man.
Back to Top

Seafood Fertilizer
During the 1700s and early 1800s, there were so many lobsters along the coast of New England that one could walk down the beach and pick them up off the sand. Lobsters were so abundant that native Americans used them as fertilizer, and colonists thought of them as food for poor people. Servants complained when they were forced to eat lobster more than three times in a week.
Today, of course, lobsters are prized as an expensive delicacy. They are hunted intensely by humans, and they are no longer so abundant. Today's wild lobsters are puny runts compared to the huge forty- pound, three-foot specimens (18 kg, 1 meter) that were once common along the New England coast.
Back to Top