New Stuff:
Adjustable Tires
The High Mobility Multi-Purpose Wheeled Vehicle (HMMWV) or Hummer is a
highly durable motor vehicle that was originally designed for military
use. A Hummer has the ability to change tire pressure while it is
moving, making it practical for travel across loose surfaces like sand
dunes.
The Hummer was designed to be dropped by parachute and land on
its wheels unharmed. Its other interesting talents include a winch
powerful enough to suspend the vehicle in midair, and, in the military
version, the ability to ford streams as deep as 60 inches (150
centimeters).
The civilian version of the Hummer, which became available in
1992, is not available with a machine gun or rocket launcher, but it is
just as durable as the military version.
(Hummer is a trademark of AM General.)
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Alien Sand Dunes
Scientists have recently discovered active sand dunes on Mars. The
Viking spacecraft, which photographed the planet in the 1970s, hinted
at the presence of sand dunes. Cameras aboard the Mars Global Surveyor
spacecraft, which is currently mapping the planet in great detail,
returned more precise images of the dunes and showed that they are
active (moving).
There are two kinds of dunes: small fields of bright dunes, which
may be made of gypsum or another sulfate mineral, and large areas of
darker dunes, which might be made of eroded particles of volcanic rock.
The Martian sand dunes form where winds bring in other particles
to replace the reddish-brown dust that accumulates in most places on
Mars. Scientists believe the winds on Mars are only strong enough to
move the sand during part of the year, because the air is too thin at
other times.
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Atomic Clocks
The most accurate clocks in the world are atomic clocks, which use the
vibrations of atoms to keep track of the time. They are so accurate
that they would gain or lose only one second in three million years.
Most clocks use mechanical or electronic oscillators (vibrators)
to count out a fixed number of "ticks" per second. The oscillators are
not all exactly the same, so ordinary clocks must be periodically
reset.
Atomic clocks use the absolutely stable vibrations of atoms
(usually cesium atoms). Since every atom of the same type vibrates
exactly the same number of times each second, atomic clocks are
extremely accurate.
The largest error in the best atomic clocks comes from slight
variations in how the atoms are moving as their vibrations are
measured. New atomic clocks will slow the atoms down almost to a stop,
making them up to 10,000 times more accurate than today's models.
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Black And White Moon
The most contrasting object in our solar system is Saturn's moon
Iapetus (eye-AP-i-tus). The albedo (reflectance) of its leading
hemisphere (the half that stays in front as it orbits Saturn) is less
than 0.05, about as dark as soot. The trailing hemisphere has an albedo
of 0.5, as bright as water ice.
The difference in brightness is so great that Iapetus'
discoverer, Giovanni Cassini, noticed he could only see the moon during
half of its orbit.
Astronomers wonder if the dark material may be debris from one of
Saturn's darker moons, Phoebe. From its density, astronomers believe
Iapetus must be made almost entirely of water ice, which makes the dark
hemisphere especially puzzling.
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Body Glue
The most abundant protein in animal tissues is collagen [KOL-uh-gen], a
kind of "glue" that holds the body together. The 14 different kinds of
collagen account for about 30% of all the protein in our bodies.
Collagen shapes the structures of tendons, bones, cartilage and
connective tissue. It also strengthens the skin, and attaches it to the
underlying muscles. It makes up most of the "gristle" part of cooked
meat.
Why is collagen such great cellular glue? Its molecules are
shaped like long, thin rods, with many attachment points where they can
be stuck together. They can form strong, rigid structures, and they can
be firmly attached to many other kinds of molecules.
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Breathable Liquid
Doctors are using a liquid called perflubron to save the lives of
people who might otherwise die of lung congestion. The non-water- based
fluid fills the lungs, displacing the watery fluids that otherwise
would accumulate there and possibly drown the patient.
Perflubron is a perfluorocarbon, a liquid that is closely related
to the plastic teflon. It does not mix with water, and it evaporates in
air. Because it carries oxygen and carbon dioxide almost as well as
plain air does, it can be used instead of air in the lungs. The
technique is called "liquid ventilation."
Tests are under way now to determine the best way to perform
liquid ventilation. It is hoped that it can be used to save the lives
of premature infants, who often experience lung failure because of
fluid accumulation.
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Brown Dwarfs
Objects that are smaller than a star but many times the size of Jupiter
are called brown dwarfs. Bearing some similarities to both planets and
stars, they do not qualify as either. Some brown dwarfs float freely in
space, and others, like planets, orbit stars. Although they are similar
to the small, dim stars called red dwarfs, brown dwarfs do not have
enough mass to start the process of hydrogen fusion in their cores, and
therefore cannot generate the same level of energy as a star.
Over billions of years a brown dwarf will slowly cool, releasing
the heat generated by the gravitational collapse which occurred when it
first formed from gas and dust. As it cools, it fades; the older a
brown dwarf is, the dimmer it is.
Until recently, brown dwarfs were purely theoretical objects;
their dark color and faint intensity made them difficult to see. New
techniques in astronomy have allowed several to be discovered, some
even quite close to our Solar System.
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Coin Notches
United States dimes, quarters, and half dollars have notches all around
their edges, but pennies and nickels have no notches.
Notches are a remnant from days when the value of a coin was
determined by the amount of silver or gold it contained. The US mint
incorporated the notches as a way of discouraging people from shaving
off small amounts of the precious metals from their coins. Less
valuable coins have always contained only cheaper metals, and so their
smooth edges were allowed to remain.
Although coins today no longer contain silver, the notches have
been kept as part of their design, and are useful for recognition by
the visually impaired.
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Complex Crystals
Mineralogists at the Canadian Museum of Nature and the University of
Copenhagen were surprised when they began analyzing specimens of
eudialyte, a mineral that is an important source of the rare, expensive
metal zirconium.
After finding inconsistencies in x-ray diffraction patterns,
which are often used to study the crystal structures of minerals, they
conducted further studies that revealed as many as 46 different
chemical elements could be part of eudialyte's crystal structure.
Eudialyte's unusually complex structure includes many places
where rare elements might be incorporated. Understanding that structure
might make the refining of zirconium and other rare elements more
practical. As a result of this study, several new varieties of
eudialyte have been discovered.
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Coral Atolls
A coral atoll is a ring-shaped island or arc of islands, made almost
entirely out of coral, with a shallow, sandy central lagoon. There are
atolls in tropical seas all over the world.
An atoll starts out as a small island of ordinary rock, often a
volcano. Coral animals settle below the tide line, building a ring-
shaped reef around the island. Then, through erosion or because of
geological forces, the island slowly sinks down.
The coral reef, however, keeps growing. It grows almost to the
surface as the land sinks, forming the distinctive ring shape. The
shallow central lagoon (where the mountain used to be) usually has a
floor of coral sand, studded with small patches of reef.
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Deepest Cave
Lechuguilla Cave, near Carlsbad, New Mexico, goes down at least 1,571
feet (479 meters), making it the deepest known cave on Earth. It is
only partially explored, but already more than 97 miles (156
kilometers) of passages have been mapped.
The immense maze of rooms and passages that forms the Lechuguilla
system was discovered in 1986. A group of spelunkers (cave explorers)
decided to investigate a desert pit called Misery Hole. When they
reached the bottom, they dug down and found a chamber from which a
howling wind emerged, a sign of a large cave system.
Unlike most limestone caves that were formed by water dissolving
the rock from above, Lechuguilla was formed by hydrogen sulfide gas
coming up from underneath. The gas was released from an underground oil
pocket because of geological shifts.
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Early Ocean Explorers
Long before Europeans set out to explore the world by sea, Polynesian
explorers had sailed across thousands of miles of open water. They
started as early as 1500 BC by exploring the nearby islands north of
New Guinea, then sailed east and north to distant, unseen lands. By
1000 AD they had settled islands scattered across much of the vast
Pacific Ocean.
The ancient Polynesians built sturdy double-hulled boats to carry
colonists and all the animals, plants, and supplies that they needed to
establish settlements. With time, they developed a sophisticated
navigation system based on the positions of stars and the patterns of
ocean swells.
By the time Captain Cook and other Europeans finally reached many
of the remote islands of the Pacific, Polynesian people had been living
there for hundreds of years.
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Electron Microscopes
Electron microscopes do not use light, and can show objects in much
greater detail than any conventional light microscope. The detail is
better because electrons are much smaller than light waves, and can be
sent and detected with extreme precision.
There are several different kinds of electron microscopes. Two of
the most frequently used types are transmission electron microscopes
and scanning electron microscopes.
A transmission electron microscope (TEM) sends electrons through
an extremely thin cross-section (slice) of an object and projects an
image of the specimen onto a screen. Many organelles (the small
structures which make up cells) were discovered with the help of
transmission electron microscopes.
A scanning electron microscope (SEM) bounces electrons off a
solid object in order to generate an image of that object's surface.
The object is coated, placed in a vacuum chamber, and electrons are
fired at it. The fired electrons "excite" electrons in the coating,
causing them to be released. Sensors detect the ejected electrons, and
a picture is constructed on a monitor screen.
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Evaporated Sea
Millions of years ago, the land at what is now the Straits Of Gibraltar
rose up, blocking off the connection between the Mediterranean Sea and
the Atlantic Ocean. Slowly, the sun did its work, and the Mediterranean
Sea evaporated, leaving behind vast layers of salt and a few shallow
salt lakes.
Geological changes continued at their slow pace. One day about
five million years ago, the Atlantic Ocean finally burst through again,
and a torrent of seawater began refilling the basin. Centuries later,
the Mediterranean Sea was full again.
A very similar event happened around 5650 BC at the mouth of what
is now the Black Sea. Once a freshwater lake, that body of water is now
much larger, containing salt water that flooded in through the Bosporus.
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Expanding Lizard
When a desert chuckwalla (Sauromalus obesus) is disturbed, it runs into
a rock crevice. If the threat persists, it puffs itself up with air,
inflating its lungs up to three times their normal volume. It becomes
tightly wedged in place, and almost impossible to remove from the
rocks.
Chuckwallas are large lizards, closely related to iguanas, which
can be up to 18 inches (46 centimeters) long. They are herbivores, with
a special preference for yellow flowers. They are common in the
southwestern US, where their favorite habitat (rocky hillsides) is
still relatively undisturbed by humans.
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Giant Antlers
The largest antlers ever were those of the now extinct Irish elk. Their
huge racks grew as large as 3.6 meters (12 feet) across, weighing more
than 40 kilograms (88 lbs). Every year, they grew a whole new set from
nubs on their heads.
These very large deer roamed across the northern hemisphere until
about 10,000 years ago, when there was a sudden cold period called the
Younger Dryas. When the climate got cold, the forests were replaced by
tundra.
Recent studies suggest that although the Irish elk were still
able to grow their huge antlers during the Younger Dryas, doing so
depleted them of calcium and phosphorus. Unable to find enough food to
restore themselves, they died out.
The largest antlers on living deer are found on the moose. Their
antlers can get as large as two meters (over six feet) across.
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Giant Construction Project
There has never been a construction project as massive and expensive as
China's Three Gorges Dam. This gigantic dam, which will be sixty
stories high and 2.3 kilometers long (1.4 miles), will create a
reservoir longer than Lake Superior. Scheduled for completion in 2009,
the Three Gorges Dam is expected to cost $27 billion and will generate
as much electricity as would 18 nuclear power plants.
The massive construction project is also highly controversial,
and has generated domestic and international opposition. The reservoir
it will create will drown many towns and villages, beautiful valleys,
and historic sites. The ecosystem of the Yangtze River downstream of
the dam will be permanently changed and some species may become extinct.
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Glass Shells
Diatoms (Bacillariophyta) are tiny, floating, one-celled life forms
that build intricate shells out of silicon dioxide, the compound found
in glass, sand, and rock crystal. Their minute shells are beautiful
structures with very tiny details, and there are thousands of
varieties.
The shell of a diatom has two halves called frustules. One of the
frustules is slightly larger than the other, and they fit together
tightly. Most diatom frustules are decorated with hundreds of tiny
holes, grooves, or bumps, arranged in regular patterns.
Diatoms have been around for hundreds of millions of years. They
are very important to Earth's ecology, producing about a quarter of all
the free oxygen in the atmosphere. Although they may seem like plants,
they have recently been assigned to a new kingdom, the Chromista, along
with some other related life forms.
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Halogen Light Bulbs
Hot-burning "halogen bulbs" can last two or three times longer than
regular bulbs because they are filled with chemically active halogen
gases that preserve the filament.
The filament of an ordinary light bulb burns out because atoms of
tungsten evaporate from its surface, so that it becomes thinner and
thinner until it breaks. The evaporated tungsten is deposited on the
inside surface of the bulb, where it forms a dark deposit.
The gas inside a halogen bulb combines with the tungsten atoms
that condense on the glass, removing the deposit. When the combined
molecules touch the hot filament, the tungsten is redeposited there,
and the gas is released to do the same trick again.
Halogen bulbs don't last forever, though. Although the filament
does not evaporate as fast, it does eventually develop thin spots, and
the bulb burns out.
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Heavy Ice
Ice cubes made out of "heavy water" will not float in ordinary water.
Normal water is made of molecules containing one atom of oxygen
and two atoms of hydrogen. Both of the hydrogen atoms in heavy water
have been replaced by deuterium. An atom of deuterium is different from
an atom of hydrogen in that it contains an extra neutron in its
nucleus, making the whole atom almost twice as heavy.
Normal ice floats in water because its density is lower than that
of water -- a result of its more open molecular structure. The extra
mass of the deuterium atoms in heavy water adds enough weight that a
heavy water ice cube sinks in ordinary water, although it still floats
in heavy water.
Heavy water is used in nuclear reactors, where it slows down the
fast neutrons emitted by the core and carries away the heat created
there.
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Hops in Beer
The sharp bite of beer is partly a result of flavor elements that come
from the conelike female flower of the hop vine (Humulus lupulus), also
known as the "spices" of beer. But hops do much more than add flavor to
beer.
Brewers began adding hops to beer in the fourteenth century, when
it was discovered that not only was the flavor better, but the beer
also held its head better (the foam lasted longer) and it was less
likely to go bad during the brewing process.
Female hops flowers contain glands that produce resins vital to
the brewing process. They change the surface tension of the liquid, so
the head is firmer, and they also interfere with the growth of
undesirable bacteria. Many complex compounds in the hops also
contribute to the distinctive flavor of beer.
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Human Genome Size
You may have heard of the recently completed "human genome project," a
monumental project undertaken to decode the entire DNA sequence of a
human being (the human genome). Just how big is that sequence?
Each human cell contains 46 chromosomes, each of which is a DNA
molecule wrapped around proteins called histones. If all the DNA
molecules in one cell were unwrapped from the histones and stretched
out end-to-end, the total length would be about six feet (2 meters).
Almost every cell in your body contains six feet of DNA, wrapped up
into a very compact space.
If all the information in the human genome were printed in small
type, it would fill a thousand thick telephone directories. The whole
sequence contains about three billion base pairs (the genetic
equivalent of alphabet letters), including some 50,000 - 100,000 genes,
each of which codes for a specific protein.
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Humming Fish
In the Pacific Ocean there are fish that make a loud humming sound.
Sometimes the sound is so loud that it can be heard by people in boats
on the surface. The sound is emitted in the spring and summer by
thousands of male midshipman fish, who sit in rocky nests at the
bottom.
The humming chorus is their way of attracting a mate, but not all
male midshipman fish are hummers. There are two kinds. The larger kind
are the ones who hum. The smaller ones, who are called "sneaker males,"
silently sneak into the nests of the hummers, depositing sperm there.
When a female midshipman fish visits the nest of a hummer male,
she deposits her eggs, which are fertilized by sperm from the hummer
male and from any sneaker males who have visited. The hummer male
raises the brood, which may include several batches of young at
different ages, from eggs deposited by different females.
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Insect Sweat
If you've ever lived where there are cicadas, you know that these
extremely noisy insects make the most racket when it's blistering hot.
How do they keep cool while remaining so active in the hot sun?
The secret is that cicadas sweat. These finger-long, winged
insects have pores through which they secrete a watery liquid derived
from the tree sap they drink. While they sing (by vibrating ridged
membranes against their bodies), they sweat profusely, thus dissipating
the heat of their efforts.
Those efforts result in the loudest sounds made by any insect. In
Missouri in the summer of 1999, the din reached 85 decibels at some
locations, louder than a large diesel truck at full power. Outdoor
cafes had to close because the noise was too much for the customers.
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Largest Eyes
The eyes of the giant squid (Architeuthis dux) can be up to 25
centimeters (ten inches) across, about the size of a volleyball. Those
large, sensitive eyes are useful in the dark waters where the giant
squid lives, 200-700 meters (660-2,300 feet) below the surface of the
ocean.
Giant squids are among the world's most mysterious megafauna
(large animals). So far, no live specimen has been captured. They live
in deep oceans all around the world, along with at least ten other
species of very large squid.
Like other cephalopods such as octopi, giant squids have complex,
well-developed brains. They are ferocious predators, but they are also
pursued and eaten by large cetaceans such as sperm whales, some of
which show the obvious scars of giant squid sucker disks.
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Largest Star
The largest known star is VV Cephei, a "red supergiant" in the
constellation Cepheus. VV Cephei's diameter is 17.7 times the size of
Earth's orbit. If it were put in the center of our solar system in
place of the sun, it would extend almost to the orbit of Saturn, and it
would swallow up Mercury, Venus, Earth, Mars, and Jupiter.
Like other supergiant stars, VV Cephei is a deep red color. It's
also known as the "garnet star." It has a small companion star that
circles it every 20.4 years. During one part of its orbit, the
companion is hidden for about 1,000 days, and accurate measurement of
that time makes it possible to calculate the main star's diameter.
VV Cephei is a massive star near the end of its life cycle.
Astronomers believe that one day in the next million years or so it
will explode into a supernova, releasing vast amounts of energy and
leaving behind a tiny but massive black hole or neutron star.
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Light Catching Chemical
Green plants gather energy from sunlight and use it to build living
tissue in a process called photosynthesis. (Oxygen is also produced,
making plants the foundation of almost all life on Earth.)
Photosynthesis begins when chlorophyll molecules catch photons
("particles") of light. A chlorophyll molecule looks like a square
plate with a long tail. When a photon strikes a magnesium atom at the
center of the square, the atom releases a high-energy electron.
The electron is captured and sent along a complicated pathway.
Along the way, its energy is collected and used to build sugar out of
carbon dioxide and water.
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Light Catching Molecule
Green plants are the foundation of almost all life on Earth, because
they collect the Sun's light energy and use it to build living tissue.
They do it by catching photons ("particles" of light) with chlorophyll
molecules in a process called photosynthesis.
A chlorophyll molecule looks like a square plate with a long
tail. At the center of the square is an atom of magnesium. When a
photon strikes the magnesium atom an electron is ejected.
The electron is then captured in the complicated molecular
structure that surrounds the chlorophyll molecule. The energy it
releases fuels a chemical reaction resulting in the creation of sugar
molecules from carbon dioxide and ater.
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Microgravity Robot
Astronauts on missions in the Space Shuttle and the International Space
Station will soon be joined by softball-size flying robots called
Personal Satellite Assistants (PSAs). These spherical machines, now
being designed in a NASA project, will move around in the weightless
crew cabin under their own air-jet propulsion.
Each PSA will have a microphone, a camera, many sensors, and
wireless data communications. A small flat-screen display will allow
the PSA to serve as a self-positioning video conferencing tool, and it
will be able to enter small spaces and send back a video feed of what
it sees, hears, and senses.
The PSA is the first generation of a whole line of robotic
assistants for space workers. We may also see "outdoor" construction
robots to build large structures in the weightless vacuum of orbit.
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Milky Way's Shape
For many years, scientists thought that our home galaxy, the Milky Way,
was a circular spiral galaxy like the nearby Andromeda Galaxy. But
recently it has become clear that the Milky Way is a "barred spiral"
galaxy.
Instead of having smooth spiral arms, our home galaxy has a
nearly straight bar of stars across the center, with spiral arms
trailing from the ends of the bar. The bar and the spiral bands are
fuzzy collections of gas, dust, and millions of stars. Our sun is
located at the edge of a spiral band, near one end of the bar.
The bar is not directly visible from Earth, because it is
obscured by vast clouds of dust. Astronomers discovered it by carefully
mapping the shape of the central bulge of stars in the Milky Way and by
observing the motions of stars.
How do barred spirals form? One theory is that the bar is a
consequence of intense magnetic fields near the center of the galaxy,
which could cause the gas, dust, and stars to orbit differently.
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Momentum Exchange Tether
An orbiting spacecraft can send another one into a higher or lower
orbit without using any fuel by simply reeling it out on a long string,
then releasing it. This is called a momentum exchange orbital tether.
Momentum exchange tethers are different from the electrodynamic
tethers described in another Cool Fact (linked below). No magnetic
field is needed and no electricity is used, so they work around planets
like Mars, which has almost no magnetic field.
One proposed system of tethers called the Lunavator would
transfer spacecraft between the Earth and the Moon by flinging them
along in relays, from one level of orbit to the next. The Lunavator
could make Earth-Moon travel much more practical, and much less
expensive.
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Most Islands in a Lake
Lake of the Woods, located at the corners of Ontario, Minnesota, and
Manitoba, contains an estimated 14,000 islands, more than any other
lake on Earth. It is also one of the most irregularly shaped lakes,
with an estimated 65,000 miles (105,000 km) of shoreline.
During the last Ice Age, the land in that area was covered by a
thick layer of ice. The ice scoured the surface, leaving many
depressions and hills. Today, the depressions are filled with water,
and a broad section of central Canada is sprinkled with thousands of
small lakes.
Around 7000 BC, Native Americans hunted in the area. Throughout
the region there are pictographs (rock art) from the Cree tribe, made
about 500 years ago. The first white man to see the lake was the French
explorer Jacques De Noyon in 1688.
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Muddiest River
The largest amount of sediment is carried by one of the world's largest
rivers, China's Hwang Ho (Yellow River). The Hwang Ho used to carry
vast amounts of yellowish silt into the Yellow Sea, but changed its
course during a disastrous flood in 1852 and now empties into the Gulf
of Chili, 400 miles further north.
This 3,000 mile-long river (4,800 km) receives most of its silt
load as it passes through an area of loess (deposits of silt or clay,
originally created as windblown dunes) just south of the Great Wall.
China has repeatedly attempted to control the Hwang Ho, but the
river, also known as "China's Sorrow," has not responded well.
Reservoirs and dredged beds fill with silt, and devastating floods are
still common.
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Nest Impostor
The cuckoo bird does not make its own nests. Instead, the female finds
a nest that has eggs in it, and lays one egg in it. The birds that made
the nest seldom notice the extra egg. This practice is called "brood
parasitism."
Cuckoo eggs hatch quickly. When the cuckoo chick emerges, the
first thing it does is push all the other eggs out of the nest. If they
hatch before it can do this, it pushes the babies out too.
The cuckoo chick, which is dutifully fed by its hosts, grows
quickly, often to a size much larger than both of them. The hungry
chick makes so much noise that the "foster parents" feed it generously.
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New Kinds of Planets
Astronomers are finding more and more planets orbiting stars outside
the solar system. Many of these "extrasolar planets" are quite strange.
One group is the "hot Jupiters." These are super-giant planets
several times the size of Jupiter, in very close orbits around their
stars. Some of them are in orbits much smaller than Mercury's orbit
around our Sun.
There are also planets that have very eccentric orbits, swinging
in close to their star and then coasting out very far away. There are
many other odd planets, including at least two that orbit around
neutron stars.
As more strange, new planets are discovered, astronomers are
scrambling to come up with explanations for how they came to be.
Existing theories of solar system formation simply do not cover such
oddities. There are many new theories.
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Nimble Insects
If you have ever tried to catch a cockroach, you know the little devils
are fast and sure-footed. A team of biologists recently discovered that
cockroaches can change course as many as 25 times in one second, making
them the most nimble animals known.
Cockroaches can run as fast as one meter (over three feet) per
second. The researchers were curious how these darkness-loving insects
managed to avoid running into obstacles, so they built a special
enclosure and filmed them at 250 frames per second.
They discovered that the roaches kept the tips of their antennae
in contact with barriers, and were able to twist and turn very rapidly
to follow the walls. Even when the insects were blindfolded with dabs
of wax, they still kept a sure course around obstacles.
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Ocean Creatures
One of the most ancient creatures in the ocean is the hagfish, which
remains virtually unchanged over its 300 million year history. This
primitive, boneless agnathan (jawless fish) looks similar to an eel,
but without visible eyes.
The hagfish is a scavenger that consumes dead creatures whose
bodies have sunk to the sea floor. When threatened, a hagfish can emit
up to a gallon of a syrupy, toxic slime, that makes it almost
impossible to capture.
There's only one problem with all that slime: the hagfish needs a
way to get rid of it after escaping the predator. It does this by tying
its own tail in a knot, then sliding the knot all the way up past its
head. When the knot pops off its head, it slips out of the slime and
swims away.
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Ocean Walking Insect
The only insects known to live directly on the surface of the open
ocean are the sea skaters (genus Halobates), close relatives of the
water striders that walk on the surfaces of ponds and streams.
Like the water striders, sea skaters have waxy hairs on their
feet that repel water, allowing them to stand on the surface tension.
They are delicate insects with long legs and highly coordinated
reflexes, enabling them to move around with great precision on the
surface of the waves.
Sea skaters are predators, able to sense the presence of small
swimming creatures just under the surface and spear them with their
sharp mouthparts. They also eat insects that fall onto the water
surface. Of course, they are themselves prey to any fish that is fast
enough to snatch them.
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Oldest Stars
Our galaxy's oldest stars are also the smallest and the most abundant,
numbering 70% of the galaxy's stars. They are red dwarfs, dim stars
that are difficult to even see. Some of these stars formed more than
ten billion years ago, and many of them are part of ancient globular
clusters, spherical collections of stars that are found in a large halo
around the galaxy.
Red dwarfs live a long time because they burn slowly. Without a
large mass of gas, they are not able to create a high temperature and
pressure in their cores where the fusion reactions take place, so the
hydrogen fuses very slowly.
Objects that gather even less mass than a red dwarf do not
generate enough internal pressure and heat to begin fusion. Unable to
"light up," they become brown dwarfs, destined to fade into
invisibility and become cold, dark balls of frozen gas.
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Penguin Boat
Instead of a propeller, the penguin flipper boat uses a pair of paddles
at the back that look and move like the flippers of a penguin. The
twelve-foot boat, invented by James Czarnowski, is called "Proteus."
The penguin flipper boat uses 17% less power than an equivalent
propeller-driven boat, and produces far less turbulence and noise. It
might be good for use in nature preserves, where propellers might cause
too much disturbance of the ecosystem.
For inspiration Czarnowski watched the penguins swimming
underwater at Boston's New England Aquarium. He mapped out the way they
moved their flippers, and designed a mechanical system to mimic it,
moving the paddles side to side while turning them at the same time.
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Prehistoric Creatures
Although science has not found a definitive answer to this question, it
is considered likely that the first animals on land were eurypterids,
primitive creatures very similar to today's scorpions. Fossil evidence
indicates that they emerged from swamps during the early Silurian
Period about 440 million years ago, approximately 200 million years
before dinosaurs first appeared.
Eurypterids were among the most successful lines of early
arthropods (animals with external skeletons). Some were giant
ocean-dwellers, as large as 2.3 meters (7 feet). As one would imagine,
they were quite formidable predators.
The first eurypterids to venture onto land didn't find very much
there. Plants had only made it to land a short while before, also
during the Silurian Period, and hadn't evolved much beyond mosses and
other simple plants.
Today's scorpions are direct descendants of the ancient
eurypterids, and have a very similar anatomy.
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Protein
The largest known single-chain protein is found in muscle cells, and is
referred to by two names: titin and connectin. This huge molecule helps
to maintain resting tension in muscle tissue and takes part in the
contraction of muscle fibers.
A molecule of titan can be nearly one micron long (0.000001 meter
or 0.00004 inch); which is bigger than some cells. Each molecule
consists of about 30,000 amino acids (the basic building blocks of
proteins).
Scientists have recently used "optical tweezers" to study titin
by carefully stretching individual molecules. They found that a
molecule of titin is something like a series of springs connected by
looser chains, allowing it to stretch and return to its original shape
easily.
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Robot Community
A scientist at the MIT Artificial Intelligence Lab has built a colony
of microrobots. The tiny machines, which are called "ants," are only
1.4 inches (3.5 cm) long. They have tractor treads, long feelers, and
jaws in front that they use to pick up their "food." They can
communicate with each other by sending and receiving infrared signals.
The microrobots live on a big, flat surface called the "ant
farm." They are learning how to play social games like "Follow The
Leader," "Tag," and "Capture The Flag."
Each "ant" has its own microprocessor (computer chip), running
software written in a style called "Subsumption Architecture," in which
complex behavior is built up from collections of simpler behaviors that
interact. As new levels of software are written, the robots will be
able to do more complex things.
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Rock Varnish
Rocks that have been exposed to the harsh conditions in the desert
often develop a hard, usually dark brown coating called "rock varnish"
or "desert varnish". By examining the varnish coat, it is possible to
measure how long the rock's surface has been undisturbed. Varnish can
also form on the surface of desert soil, if it has been undisturbed for
thousands of years.
"Rock varnish" is composed of oxides of iron and manganese,
together with clay particles, cemented together by living bacteria. It
tends to become darker with time. Some varnished rocks that have been
untouched for tens of thousands of years are nearly black.
Native Americans used hard stones to scratch pictures in the dark
varnish coating, allowing the natural light-color of the rocks beneath
to come through. These durable images, called petroglyphs, can be seen
throughout the American southwest.
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Rotary Rocket
The Roton Rotary Rocket not only has blades at the top, like the blades
of a helicopter, it also has a rocket motor at the bottom that spins.
It's a design for a fully reusable, manned, Earth-to-orbit spacecraft
that only uses one stage.
The spinning rocket motor is more efficient than an ordinary
rocket because no complicated, heavy fuel pumps are needed. The spin of
the rocket motor causes the fuel to flow out toward the nozzles, where
it mixes and burns.
On re-entry, the helicopter-like blades at the top are deployed.
At first they spin passively, slowing down the craft as it enters the
atmosphere. But later, small rockets at the tips of the blades are
ignited, and the rotary rocket becomes able to hover and make a
delicately controlled soft landing, tail first.
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Round Portholes
Portholes on ships are round for the same reason that submarine hatches
have round corners and airliners have rounded windows. In all these
cases, the vehicle is subject to flexing and mechanical stress. If the
windows had sharp corners, the stresses would concentrate there,
resulting in material fatigue and eventually cracking. With round or
rounded windows, the stress is evenly distributed.
Large boats like cruise liners can have rectangular picture
windows in some places because the local stresses there are smaller.
Some early commercial airplanes had large, rectangular windows,
and the skin of the planes had a tendency to crack at the corners.
Today's pressurized airliners have much smaller, rounded windows.
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Scale Eaters
Fish in the genus Perissodus eat mouthfuls of scales from the sides of
other fish. These strange predators live in Africa's Lake Tanganyika,
where they form part of one of the most diverse freshwater ecosystems
on Earth.
Each Perissodus individual is left-biting or right-biting. Its
mouth curves to the left or to the right, and it can only steal scales
from one side of its prey. The number of left-biting and right-biting
fish is roughly equal.
The scale-stealing Perissodus are cichlids, part of a family of
fish that became isolated in Eastern African lakes millions of years
ago. The family includes hundreds of specialized kinds of fish, with
many different feeding and breeding habits. All of them evolved since
the lakes were isolated.
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Shrinking Compound
Heating increases the motion of atoms, causing most substances to
expand, but a ceramic called zirconium tungstate shrinks. One of the
few known "heat shrinking" compounds, it shows this strange behavior
over the widest range of temperatures, from near absolute zero
(-273°C or 460°F) up to a red-hot 777°C (1431°F)!
Zirconium tungstate shrinks because of the unusual way in which
its oxygen atoms are bonded. When they vibrate they tend to pull the
zirconium and tungsten atoms closer together, causing the substance to
shrink.
"Materials scientists" are looking for useful ways to use
zirconium tungstate. One idea is to mix it with other compounds to
create materials that do not shrink or expand with changing temperature.
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Sinking Ground
In Arizona, California, and hundreds of places throughout the world,
the ground has been sinking for years. Some places in California's
Imperial Valley have subsided more than 25 feet in the past century.
Why is the ground sinking?
In almost all cases, ground subsidence is caused by the removal
of fluids from beneath the ground, allowing the rock layers to settle
and compress. It is usually caused by removal of groundwater, but
sinking ground can also be caused by the removal of oil or even natural
gas, or by the draining of wetlands.
Ground subsidence is a growing problem in many places. Deep
fissures can form, cutting across roads, farms, and buildings, and the
land can slowly tilt. The only solution is to stop drawing out
groundwater, which becomes less likely as people around the world
continue to face increasing water shortages.
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Slow Heart
Throughout the animal kingdom, there is a general relationship between
an animal's size and how fast its heart beats: the larger the animal,
the slower its heart beats. An adult blue whale with a heart the size
of a small car has one of the slowest heart rates of all.
Researchers have been able to record whale heartbeats directly by
listening to them from inside of submarines. When it is at the surface,
a whale typically has a heart rate of about five or six beats per
minute. When it dives, the whale's heart slows down to about three
beats per minute.
The whale's heart slows down when it dives in order to save
oxygen, and to keep the precious substance in the central body rather
than letting it get used up in the fins, skin, and other outer body
parts.
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Smart Birds
Ravens and their smaller cousins, crows, are among the smartest birds.
Not only can they untie knots, they can also unzip zippers and unfasten
velcro. Ravens have a highly sophisticated language with hundreds of
distinct sounds. They are highly social birds, who mate for life and
play complex games with each other.
Ravens are the largest perching birds. They can have up to a
four- foot (1.2 meter) wingspan, and they are powerful fliers with
tremendous endurance. They live all around the northern hemisphere,
from tropical jungles to the snowy wastes of the high Arctic. Their
high intelligence and endurance give them the ability to adapt to many
conditions and eat a wide variety of foods.
For years ravens were thought of as pests in the United States.
They were seen as thieves of eggs and small barnyard animals, and shot
on sight. Their numbers declined steadily until recently, but now they
are recovering across the western and northern states, learning to
coexist with the humans who were once their main enemy.
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Spherical Fish
A pufferfish responds to stress by gulping a huge amount of water,
expanding itself in a few seconds into a hard ball three times as large
as the resting fish. Some species have sharp spines that pop out
straight when the fish puffs up, making them particularly nasty if
eaten by a predator.
When it puffs up, a pufferfish's stomach expands to 100 times its
normal volume. Its abdominal cavity is lined with folded, pleated
tissue, and some of its ribs are missing, making it easier to inflate.
Its skin is threaded with thousands of fibers that snap tight when it
is fully inflated.
Pufferfish are relatives of sunfish and triggerfish. They are
awkward looking fish, with a boxy shape, and they do not swim very
well. They rely on their unusual defense (and recognition by predators)
to protect them.
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Sunken Continent
In the southern Indian Ocean, about 4000 kilometers (2500 miles)
southwest of Australia, there is a very large undersea plateau called
Kerguelen. In the last 110 million years, Kerguelen has risen above the
waves and re-submerged three times.
Scientists discovered Kerguelen's past by examining deep core
samples and reconstructing the movement of the Earth's crustal plates.
Kerguelen rose above the water about 110 million years ago, then
submerged. The land rose again 85 million years ago, and broke the
surface once more 35 million years ago.
Scientists believe the force that lifted the sunken continent was
generated by gigantic injections of volcanic magma deep beneath the
Earth's crust. When the underground activity subsided, the plateau sank
again.
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Sun's Core
The temperature at the sun's core is thought to be about 15 million
degrees C (27 million degrees F), by far the hottest temperature in the
solar system. The material there is plasma, a gas of electrons and
atomic nuclei, compressed to about ten times the density of lead.
The sun's nuclear fusion reactions only happen in the innermost
core, where the pressure and temperature are high enough to fuse
hydrogen into helium. The energy generated there starts out as high
energy gamma rays and x-rays, not as visible light.
The energy released by fusion makes its way out from the core
through several layers, colliding with the dense plasma all the way. It
takes about a million years for each photon (energy "particle") to
reach the surface of the sun. By that time the energy has been divided
and down- shifted by collisions, until it's mostly visible light.
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Swimming Ants
The only known swimming ants live in the tendrils of a pitcher plant
called Nepenthes. The ants swim around in the digestive fluid that
collects inside the plant's insect-trapping pitcher leaves. The ants
avoid being digested by the juices the plant secretes, although how
they do this is not understood.
When a large insect falls in and drowns, the ants pull it out of
the water and eats it. By pulling out large insects, the ants keep the
pitcher from being fouled by too many decaying insect bodies. But small
insects are allowed to decompose in the water, where their substance
can be absorbed by the plant.
The pitcher plant benefits from this arrangement because its
digestive fluid is kept fresh and pure, and the ants also protect it
from insect pests. The ants get a safe place to live and a regular
supply of insects to eat.
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Thickest Skin
The thickest skin in the animal kingdom belongs to beluga whales
(Delphinapterus leucas), the beautiful white whales found in the Arctic
Ocean. Their skin can be as thick as 1 centimeter (0.39 inch). By
contrast, the thickest human skin is only 2.5 millimeters thick (0.1
inch).
Unlike other whales, belugas go through an annual summer molt,
during which they shed the outer layers of their skin. During the molt,
they rub themselves on gravel beds or other rough surfaces, exposing
fresh, pure white skin.
In the Inuit language, the thick skin of beluga whales is called
muktuk. Muktuk is an important part of the Inuit diet, because it
contains as much vitamin C as oranges, more than any other animal
source.
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Tree Kangaroos
In the rain forests of New Guinea and northern Australia, there are
kangaroos (in the genus Dendrolagus) that live in trees.
Although they are adept at climbing, tree kangaroos can't move
well on open ground, where they are not able to make more than two or
three "kangaroo hops" at a time. Occasionally, they have been seen to
make astounding leaps of up to 18 meters (59 feet) from trees to the
ground.
Dendrolagus kangaroos eat leaves, fruits, flowers, and grass.
Much of what they eat is not very nutritious, but their stomachs
contain millions of tiny worms and bacteria that help break down their
leafy diet.
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Twig Camouflage
Worldwide, there are almost three thousand species of stick insects
(family Phasmitidae). These long, very thin, plant-eating creatures
have evolved to resemble the stems of the plants they eat. Some
Indonesian species can get up to a foot long (30 cm), making them the
longest insects alive today.
Looking like a stick is great camouflage, but some stick insects
take the disguise even farther. If they are too violently disturbed,
they drop to the ground, playing dead. Some even "break" by releasing a
leg or two.
Stick insects belong to the order Orthoptera, along with their
relatives the grasshoppers, crickets, mantids, and cockroaches. Like
other Orthopterans, stick insects hatch from eggs as nymphs that
resemble the adult insects.
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Ultra-thin Layers
By using "molecular beam epitaxy," (MBE) technologists can create
substances composed of many layers of different materials, in which
each layer is only one molecule thick.
In MBE, a very clean crystal surface is placed in a high vacuum
and chilled. Molecules are allowed to evaporate from a heated crucible,
and they cling to the chilled crystal surface. It is possible to
control conditions so well that layers one molecule thick are created.
Epitaxy is used in the manufacture of computer chips. Microscopic
lasers and light sensors can also be built, making possible new kinds
of computers based on light instead of electricity.
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Whale Ancestors
Until recently, no one knew what sort of animals evolved into whales
because the only fossils of whale-like creatures were fully adapted to
the ocean. Whales evolved from land-walking mammals, but what were they
like?
Fossils discovered in 1983 in Pakistan helped to fill in this
"missing link." The fossil skull of an animal called Pakicetus from 50
million years ago shows that whale ancestors were water-loving
predators ranging from wolf-size to bear-size. They swam in shallow
freshwater streams, and had ears adapted for listening underwater.
Since 1983, even earlier whale ancestors have been discovered.
Another early whale was discovered in 1994. Called Ambulocetus,
it was a marine mammal that swam by flexing its spine the way modern
whales do. Analysis of oxygen in its bones suggests that it needed to
stay close to shore because it had not yet developed the ability to
drink salt water as modern whales do.
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Video Games:
was the first console to implement
online play over a phone line, calling the system Sega Net.
• The Microsoft XBox is the
first video game system to completely support HDTV.
• Popular Science
recognized the Sega Dreamcast as one of the most important and
innovative products of 1999.
• The Magnavox Odyssey,
released in 1972, contained 40 transistors and no microprocessor. The
new Pentium 4 microprocessor contains 42 million transistors on the
chip itself!
• The PlayStation 2 is the
first system to have graphics capability better than that of the
leading-edge personal computer at the time of its release.
• The Nintendo N64 marked
the first time that computer graphics workstation manufacturer Silicon
Graphics Inc. (SGI) developed game hardware technology.
• While the original Atari
Football game was first created in 1973, it wasn't released until 1978.
It was delayed because the game couldn't scroll the screen -- players
couldn't move beyond the area shown on the monitor. When the game was
finally released, it became the first game to utilize scrolling, a key
part of many games today.
• The Atari Pong video game
console was the No. 1 selling item for the holiday season in 1975.
• The first console to have
games available in the form of add-on cartridges was the Fairchild
Channel F console, introduced in August 1976.
• The PlayStation 2 is the
first video game system to use DVD technology.
• On the original Magnavox
Odyssey, players had to keep score themselves because the machine
couldn't.
• The Nintendo GameCube's
proprietary disc can hold 1.5 gigabytes of data -- 190 times more than
what an N64 game cartridge can hold.
• On the market from 1991
till 2004, the SNK NeoGeo AES has tied the Atari 2600 (1977-1990) as
the longest supported gaming console in history.
• The Sega Genesis featured
a version of the same Motorola processor that powered the original
Apple Macintosh computer.
• Mattel's Intellivison
system, introduced in 1980, featured an add-on called "PlayCable,"
which delivered games by cable TV.
• Nintendo's Game Boy is
the most successful game system ever, with more than 100 million units
sold worldwide.
• The word atari comes from
the ancient Japanese game of Go and means "you are about to be
engulfed." Technically, it is the word used by a player to inform his
opponent that he is about to lose, similar to "check" in chess.
• In the 1980s, a service
called Gameline allowed users to download games to the Atari 2600 over
regular phone lines. It was not a success, but did form part of the
foundation for America Online, the world's largest Internet service
provider.
• The first color portable
video game system was the Atari Lynx, introduced in 1989 and priced at
$149.
• Introduced in 1993, the
3DO was the first video game system to be based entirely on CD
technology.
• The Sony PlayStation was
originally intended as a CD add-on to the Super Nintendo. When
licensing problems and other issues arose, Sony decided to develop the
PlayStation as a machine of its own.
Earthquakes:
The largest recorded earthquake in
the United States was a magnitude 9.2 that struck Prince William Sound,
Alaska on Good Friday, March 28, 1964.
2. The largest
recorded earthquake in the world was a magnitude 9.5 (Mw) in Chile on
May 22, 1960.
3. The earliest
reported earthquake in California was felt in 1769 by the exploring
expedition of Gaspar de Portola while the group was camping about 48
kilometers (30 miles) southeast of Los Angeles.
4. Before electronics
allowed recordings of large earthquakes, scientists built large
spring-pendulum seismometers in an attempt to record the long-period
motion produced by such quakes. The largest one weighed about 15 tons.
There is a medium-sized one three stories high in Mexico City that is
still in operation.
5. The average
rate of motion across the San Andreas Fault Zone during the past 3
million years is 56 mm/yr (2 in/yr). This is about the same rate at
which your fingernails grow. Assuming this rate continues, scientists
project that Los Angeles and San Francisco will be adjacent to one
another in approximately 15 million years.
6. The East African
Rift System is a 50-60 km (31-37 miles) wide zone of active volcanics
and faulting that extends north-south in eastern Africa for more than
3000 km (1864 miles) from Ethiopia in the north to Zambezi in the
south. It is a rare example of an active continental rift zone, where a
continental plate is attempting to split into two plates which are
moving away from one another.
7. The first
"pendulum seismoscope" to measure the shaking of the ground during an
earthquake was developed in 1751, and it wasn't until 1855 that faults
were recognized as the source of earthquakes.
8. Moonquakes
("earthquakes" on the moon) do occur, but they happen less frequently
and have smaller magnitudes than earthquakes on the Earth. It appears
they are related to the tidal stresses associated with the varying
distance between the Earth and Moon. They also occur at great depth,
about halfway between the surface and the center of the moon.
9. Although both are
sea waves, a tsunami and a tidal wave are two different unrelated
phenomenona. A tidal wave is a large sea wave produced by high winds,
and a tsunami is a sea wave caused by an underwater earthquake or
landslide (usually triggered by an earthquake) displacing the ocean
water.
10. The
hypocenter of an earthquake is the location beneath the earth's surface
where the rupture of the fault begins. The epicenter of an earthquake
is the location directly above the hypocenter on the surface of the
earth.
11. The greatest
mountain range is the Mid-Ocean Ridge, extending 64,374 km (40,000 mi)
from the Arctic Ocean to the Atlantic Ocean, around Africa, Asia, and
Australia, and under the Pacific Ocean to the west coast of North
America. It has a greatest height of 4207 m (13,800 ft) above the base
ocean depth.
12. The world's
greatest land mountain range is the Himalaya-Karakoram. It countains 96
of the world's 109 peaks of over 7317 m (24,000 ft). The longest range
is the Andes of South America which is 7564 km (4700 mi) in length.
Both were created bythe movement of tectonic plates.
13. It is estimated that
there are 500,000 detectable earthquakes in the world each year.
100,000 of those can be felt, and 100 of them cause damage.
14. It is thought
that more damage was done by the resulting fire after the 1906 San
Francisco earthquake than by the earthquake itself.
15. A seiche
(pronounced SAYSH) is what happens in the swimming pools of
Californians during and after an earthquake. It is "an internal wave
oscillating in a body of water" or, in other words, it is the sloshing
of the water in your swimming pool, or any body of water, caused by the
ground shaking in an earthquake. It may continue for a few moments or
hours, long after the generating force is gone. A seiche can also be
caused by wind or tides.
16. Each year the southern
California area has about 10,000 earthquakes. Most of them are so small
that they are not felt. Only several hundred are greater than magnitude
3.0, and only about 15-20 are greater than magnitude 4.0. If there is a
large earthquake, however, the aftershock sequence will produce many
more earthquakes of all magnitudes for many months.
17. The
magnitude of an earthquake is a measured value of the earthquake size.
The magnitude is the same no matter where you are, or how strong or
weak the shaking was in various locations.
The intensity of an earthquake is a measure of the shaking
created by the earthquake, and this value does vary with location.
18. The Wasatch
Range, with its outstanding ski areas, runs North-South through Utah,
and like all mountain ranges it was produced by a series of
earthquakes. The 386 km (240-mile)-long Wasatch Fault is made up of
several segments, each capable of producing up to a M7.5 earthquake.
During the past 6000 years, there has been a M6.5+ about once every 350
years, and it has been 150 years since the last powerful earthquake.
19. There is no such
thing as "earthquake weather". Statistically, there is an equal
distribution of earthquakes in cold weather, hot weather, rainy
weather, etc. Furthermore, there is no physical way that the weather
could affect the forces several miles beneath the surface of the earth.
The changes in barometric pressure in the atmosphere are very small
compared to the forces in the crust, and the effect of the barometric
pressure does not reach beneath the soil.
20. From 1975-1995
there were only four states that did not have any earthquakes. They
were: Florida, Iowa, North Dakota, and Wisconsin.
21. The core of
the earth was the first internal structural element to be identified.
In 1906 R.D. Oldham discovered it from his studies of earthquake
records. The inner core is solid, and the outer core is liquid and so
does not transmit the shear wave energy released during an earthquake.
22. The swimming pool at
the University of Arizona in Tucson lost water from sloshing (seiche)
caused by the 1985 M8.1 Michoacan, Mexico earthquake 2000 km (1240
miles) away.
23. Earthquakes occur in
the central portion of the United States too! Some very powerful
earthquakes occurred along the New Madrid fault in the Mississippi
Valley in 1811-1812. The effects of shaking from these magnitude 8+
earthquakes caused church bells to ring in Boston, Massachusetts,
nearly 1600 km (1000 miles) away.
24. Most earthquakes occur
at depths of less than 80 km (50 miles) from the Earth's surface.
25. The San
Andreas fault is NOT a single, continuous fault, but rather is actually
a fault zone made up of many segments. Movement may occur along any of
the many fault segments along the zone at any time. The San Andreas
fault system is more that 1300 km (800 miles) long, and in some spots
is as much as 16 km (10 miles) deep.
26. The world's
deadliest recorded earthquake occurred in 1557 in central China. It
struck a region where most people lived in caves carved from soft rock.
These dwellings collapsed during the earthquake, killing an estimated
830,000 people. In 1976 another deadly earthquake struck in Tangshan,
China, where more than 250,000 people were killed.
27. Florida and North
Dakota have the smallest number of earthquakes in the United States.
28. The deepest
earthquakes typically occur at plate boundaries where the Earth's crust
is being subducted into the Earth's mantle. These occur as deep as 750
km (400 miles) below the surface.
29. Alaska is the
most earthquake-prone state and one of the most seismically active
regions in the world. Alaska experiences a magnitude 7 earthquake
almost every year, and a magnitude 8 or greater earthquake on average
every 14 years.
30. The majority of
the earthquakes and volcanic eruptions occur along plate boundaries
such as the boundary between the Pacific Plate and the North American
plate. One of the most active plate boundaries where earthquakes and
eruptions are frequent, for example, is around the massive Pacific
Plate commonly referred to as the Pacific Ring of Fire.
31. The earliest recorded
evidence of an earthquake has been traced back to 1831 BC in the
Shandong province of China, but there is a fairly complete record
starting in 780 BC during the Zhou Dynasty in China.
32. It was recognized as
early as 350 BC by the Greek scientist Aristotle that soft ground
shakes more than hard rock in an earthquake.
33. The cause of
earthquakes was stated correctly in 1760 by British engineer John
Michell, one of the first fathers of seismology, in a memoir where he
wrote that earthquakes and the waves of energy that they make are
caused by "shifting masses of rock miles below the surface".
34. In 1663 the European
settlers experienced their first earthquake in America.
35. Human beings can
detect sounds in the frequency range 20-10,000 Hertz. If a P wave
refracts out of the rock surface into the air, and it has a frequency
in the audible range, it will be heard as a rumble. Most earthquake
waves have a frequency of less than 20 Hz, so the waves themselves are
usually not heard. Most of the rumbling noise heard during an
earthquake is the building and its contents moving.
36. When the Chilean
earthquake occurred in 1960, seismographs recorded seismic waves that
traveled all around the Earth. These seismic waves shook the entire
earth for many days! This phenomenon is called the free oscillation of
the Earth.
37. The San Andreas Fault
was named in 1895 by geologist A.C. Lawson. He named it after the San
Andreas Lake, a sag pond through which the fault passes about 20 miles
south of San Francisco. He likely did not realize at the time that the
fault ran almost the entire length of California
1.Evidence shows that bats (the animals)
have been around for about 50 million years.
2.
» Canadian researchers have found that Einstein's brain was
15% wider than normal.
» The actor who played Wedge in the original Star Wars
trilogy has a famous nephew: actor Ewan McGregor, who plays the young
Obi-Wan in the new Star Wars film.
» Peter Mayhew, who played Chewbacca in the first three
Star Wars movies, was a hospital porter in London before starring as
the Wookie.
» Sheryl Crow's front two teeth are fake - she had them
knocked out when she tripped on the stage earlier in her career.
» Hitler was claustrophobic. The large elevator leading to
his eagles nest in the Austrian Alps was mirrored so it would appear
larger and more open.
» Jim Morrison, of the 60's rock group The Doors, was the
first rock star to be arrested on stage.
» Hans Christian Andersen, creator of fairy tales, was
word-blind. He never learned to spell correctly, and his publishers
always had the spelling errors corrected.
» Dutch painter Vincent van Gogh cut off his left ear. His
"Self-portrait with Bandaged Ear'' shows the right one bandaged because
he painted the mirror image.
» The only married couple to fly together in space were Jan
Davis and Mark Lee, who flew aboard the Endeavour space shuttle from
September 12-20, 1992.
» Besides Star Trek, William Shatner, Leonard Nemoy, James
Doohan, and Geoge Takei have all appeared at one time or another on
"The Twilight Zone."
» The original captain of Star Trek's starship "Enterprise"
was Jeffrey Hunter - not William Shatner - as Christopher Pike, in the
pilot episode "The cage" (1964). The cast was quite different from that
of the classic series except for Leonard Nimoy as Spock.
» Screech, from "Saved by the Bell," was the only one of
the characters who played in all the episodes from the junior high,
with Mrs. Bliss, to "Saved by the Bell: The New Class."
» Betsy Ross and Elvis Presley were the only real people to
ever have been the head on a Pez dispenser. The Elvis Pez dispenser was
named "Elvis Pezly."
» Michael Jordan makes more money from Nike annually than
all of the Nike factory workers in Malaysia combined.
» Isaac Asimov is the only author to have a book in every
Dewey-decimal category.
» If Barbie were life-size her measurements would be
39-23-33. She would stand 7 feet (2 m) 2 inches (5 cm) tall and have a
neck twice the length of a normal human's neck.
» The world's longest name officially used by a person is
"Adolph Blaine Charles David Earl Frederick Gerald Hubert Irvin John
Kenneth Lloyd Martin Nero Oliver Paul Quincy Randolph Shermasn Thomas
Uncas Victor William Xerxes Yancy Zeus
Wolfeschlegelsteinhausenbergerdorft Senior" which is composed of 28
words or 192 letters.
» Adolf Hitler's mother seriously considered having an
abortion but was talked out of it by her doctor.
» Queen Victoria eased the discomfort of her menstrual
cramps by having her doctor supply her with marijuana.
» One of the many Tarzans, Karmuala Searlel, was mauled to death
by a raging elephant on set.
» All U.S Presidents have worn glasses. Some just didn't
like being seen wearing them in public.
» Gary Burgoff (Radar on MASH) always kept his left hand
out of the view of the camera, either in his pocket or under a
clipboard, because his left had is deformed.
» Ernest Vincent Wright wrote a novel, "Gadsby", which
contains over 50,000 words none of them with the letter "E."
» The Beatles song "Dear Prudence" was written about Mia
Farrow's sister, Prudence, when she wouldn't come out and play with Mia
and the Beatles at a religious retreat in India.
» Orville Wright was involved in the first aircraft
accident. His passenger, a Frenchman, was killed.
» Born on November 2, 1718, British politician, John
Montagu, the 4th Earl of Sandwich, is credited with naming the
"sandwich". He developed a habit of eating beef between slice of toast
so he could continue to play cards uninterrupted.
» The sound of E.T. walking was made by someone squishing
her hands in jelly.
» Cher's last name was "Sarkissian." She changed it because
no one could pronounce it.
» Marie Curie, the Nobel Prize winning scientist whom
discovered radium, died on 4th July 1934 of radiation poisoning.
» Scientist John Harvey owns Einstein's brain. Harvey was a
pathologist at a small hospital in Princeton, NJ, when Einstein died in
1955 at the age of 76. Harvey performed the autopsy, determined
Einstein died of natural causes, and took the brain home with him.
» Sir Isaac Newton was only 23 years old when he discovered
the law of universal gravitation.
» Mark Twain, real name Samuel Clemens, worked on a
riverboat when he was a teenager. The call "Mark twain!" meant that the
water was deep enough to proceed safely.
» Elvis' hair color was originally blonde. He dyed it black
because he was a big fan of Roy Orbison.
