Where are the hottest volcanoes in the solar system?
The hottest known volcanoes are on Jupiter's moon, Io. The lava
that emerges from Io's volcanoes can be as hot as 1800 degrees
Kelvin (1527 degrees Centigrade), about one third as hot as the
surface of the Sun.
The heat of Io's volcanoes is generated by the tidal flexing of
the moon under the gravitational stress of Jupiter and two of its
other moons, Europa and Ganymede. As Io orbits Jupiter it changes
shape slightly, and its interior is heated.
Although Io's interior is utra-hot, its surface is very cold.
Gas emitted from the volcanoes arcs high into the vacuum of space,
where it freezes into fine snow and falls back down to Io, coating
its surface with multicolored deposits.
What were the largest crocodiles that ever lived?
According to the fossil record, the largest crocodilians that ever
existed were the gigantic Deinosuchus ("terrible crocodile"), which
lived during the late Cretaceous (85 to 66 million years ago). These
giant semi-aquatic predators may have grown as long as 15 meters (50
feet).
During that time, a shallow sea called Tethys covered much of what is
now the central United States. Deinosuchus lived in swamps and
estuaries along the edges of the Tethys Sea, where it was probably
able to capture and devour even large dinosaurs.
Deinosuchus was a distant ancestor of modern crocodiles and
alligators. Few fossils of it have been found, but one skull is
almost six feet long (two meters).
What happens when galaxies collide?
The collision of two galaxies takes hundreds of millions of years.
Galaxies do not actually crash into each other, because they are
mostly empty space. Instead, they pass through each other, becoming
distorted by gravitational interactions.
Even though colliding galaxies may contain hundreds of billions of
stars, very few stars collide with each other or even come close,
because the stars are so far apart relative to their size. But
planets orbiting those stars might be tossed into new orbits by the
gravity of passing stars.
As galaxies pass through each other, the gases they contain can heat
up and collapse, forming "starburst" areas rich with bright new star
systems. Colliding galaxies may merge into one larger galaxy, or
pass completely through each other.
How is glass made into perfectly flat panes?
The very first flat glass was made by the Romans, who rolled partly
melted glass on a flat surface, or cast it into molds. The resulting
small panes were cloudy and uneven, but they were transparent.
Through the late 1800s, flat glass was made with the Crown method in
which blown spheres were reheated, punctured, and spun into a nearly
flat disc. These circular panes had a defect at the center called
the bullion. In the early 1900s, rolled glass panes were produced by
factory machines. But in 1959, a new method made all the rest
obsolete.
Today, optically clear panes are made by the "Pilkington float"
method. Molten glass is poured onto the surface of a bath of molten
tin, under a chemically controlled atmosphere. The glass spreads out
into a perfectly flat layer and solidifies into a clear pane.
When were sneakers invented?
The first shoes designed just for sports were Keds, available July
14, 1916, introducing a shoe category that later came to be known as
sneakers. In 1917, similar shoes from Converse Rubber Company also
became available.
By today's standards, the first sneakers were very primitive. They
had rubber soles, canvas sides, and long laces to hold the whole
thing together. But they were a vast improvement over all-leather
shoes, and they made a big difference in several sports, especially
basketball and tennis.
Modern sporting shoes now come in hundreds of varieties, and they are
vastly more evolved, with complex, high-tech materials. Today's
sports shoes are designed using sophisticated computer software, and
are extensively tested.
Who was the world's first paleontologist?
The first person who conducted a detailed scientific investigation of
fossils was Nicholas Steno, physician to the Duke Of Florence. Steno
is also known as the "Father of Paleontology."
In 1667, he published a book called "The Head Of A Shark Dissected"
in which he compared the teeth of caught sharks to stones dug out of
soft rocks on Malta. He concluded that the stones were actually the
teeth of extremely large sharks. Steno's book contained the first
known published illustration of a fossil.
Nicholas Steno's work is important because it helped to establish the
modern scientific view of geological history, in which Earth was
formed billions of years ago and has undergone tremendous changes
since then.
What was the first hard disk memory device?
The world's first hard disk memory storage device was IBM's 350
RAMAC Disk File (Random Access Method of Accounting and
Controlling), first offered in September, 1956.
The 350 RAMAC was the first storage device with random access to
large volumes of data. (Random access means that any of the data
is available in a short time.) It used fifty 24-inch (61-cm)
platters, holding 5 million 7-bit characters of data (roughly
equivalent to 4.9 megabytes). It could be leased for $35,000 per
year.
At the end of 1999, it was possible to buy a 50-gigabyte (50
billion bytes) hard disk for less than $1,600. That's more than
ten thousand times as much storage as the 350 RAMAC, and the
device itself is much more reliable and much faster.
Why are dalmatians often seen with firemen?
Dalmatians are among the most ancient breeds of dogs. Once known as
coach dogs or carriage dogs, they ran alongside moving coaches,
protecting them from robbers by raising an alarm, and keeping stray
dogs from interfering with the horses. It is thought that the modern
strain of the breed originated in a part of western Yugoslavia called
Dalmatia.
Bred for endurance and reliability, coach dogs could run long
distances without tiring. They had a natural affinity for horses,
and their black and white spots made them easy for the horses to
distinguish from other dogs.
When horse-drawn fire wagons were invented, dalmatians were the
natural choice to run alongside, protecting the horses from other
animals and sending out their distinctive barks to help warn people
that the fire brigade was coming.
What's the fastest that humans have ever traveled?
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.
What place has the largest variety of snakes?
Of all the natural sites ever surveyed, the most different kinds of
snakes have been found at Tam Dao ("Three Islands"), a mountain range
in northern Vietnam. So far, 108 kinds of snakes have been found in
the wet jungle there, and it is likely there are many more.
Just 32 miles (52 km) from Hanoi, Tam Dao is one of the newest
national parks in Vietnam, a country whose rich natural heritage is
only beginning to be discovered. Unfortunately, its fabulous
ecosystems are threatened by human activities, including casual
visitors and poachers.
The 108 species of snakes at Tam Dao represent four percent of the
total number of snake species in the world.
Where are the coldest volcanoes in the solar system?
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.
What moon has the closest orbit to its planet?
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.
Where are the brightest auroras in the solar system?
Auroras (or aurorae) are glowing displays produced when charged
particles stream down into a planet's atmosphere from space. The
brightest auroras in the solar system are those of Jupiter, the
largest planet, whose auroras are 1,000 times brighter than those of
Earth.
Jupiter's auroras are made by particles from its highly active moon,
Io. Volcanoes on Io spew electrons and other particles into the
region around Jupiter, and they are funneled into Jupiter's polar
regions by the planet's enormous magnetic field.
Recent studies have shown that Jupiter's auroras are connected to
many other fascinating phenomena. There are mysterious "electrojets"
of charged particles that race around the planet's poles faster than
the speed of sound, and a strange "skirt" of particles that rotates
with the planet.
Why does the bride stand to the groom's left?
In western marriage ceremonies, the bride always stands to the
groom's left. This tradition is extremely ancient.
In medieval times, humans lived mostly in small, isolated villages,
and there were not many young brides to choose from. Men who wanted
to marry sometimes had to go to neighboring villages and do what
essentially amounted to kidnapping a young maiden.
Naturally, the maiden's relatives often objected to this practice.
Just in case of trouble, the groom would keep his sword at hand, even
during the wedding itself. Since he might be attacked at any time,
he kept the bride on his left, so that his good right sword arm would
be free.
What living tissue contains no blood vessels?
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.
Is it bad luck to walk under a ladder?
Most people walk around a ladder, because walking underneath is
thought to bring bad luck. While we don't know if the superstition
is actually true, we do know how it got started.
A ladder leaning against a wall forms a triangle with the wall and
the ground. That three-pointed shape was seen in medieval times as
an example of the mystic number three, a sign of the Holy Trinity
(Father, Son, and Holy Spirit). To walk through that triangle was
thought to be a defiance of the Trinity, risking divine wrath.
Of course, it's also true that if you walk under a ladder, someone on
the ladder might accidentally drop a bucket of paint or a hammer on
you. We suggest caution in all investigations of this superstition.
Who first used the freeze-drying process?
The process of freeze-drying was first used by the Incas of Peru who
stored their vegetables near the peaks of high mountains. There,
they froze solid. Over time, the frozen water sublimated into the
thin mountain air (converted directly to vapor without passing
through the liquid state), leaving behind the perfectly preserved,
dessicated vegetables.
Modern freeze-drying started during World War II to preserve
blood plasma for use at the front lines. Today, freeze-drying is
done using flash-freezing and vacuum dehydration. Freeze-drying
preserves almost all the nutrients of foods, as well as the important
flavor elements.
What kind of galaxy has a bright ring of stars?
When two spiral galaxies collide, sometimes they pass right through
each other. If they collide head-on with just the right speed and
angle, one of them may develop a bright ring of newly-born stars
around its central core, millions of years later.
Stars are formed in galactic collisions because the gas and dust in
the colliding galaxies crashes together, heating up and condensing
into whirlpools. These whirlpools can form into stars if they are
large enough.
Galactic collisions take hundreds of millions of years. Astronomers
suspect that large galaxies like our Milky Way were formed over
billions of years by the collisions of many smaller ones.
Why are cats' tongues so rough?
A cat's tongue is actually a very sophisticated cleaning device, in
addition to its other functions. It is covered with tiny, hooklike,
backward-pointing extensions called papillae, something like one half
of a velcro connector.
When it cleans its fur by licking with its tongue, a cat is pulling
these hooks through the fur. As the hooks pass through, they pick up
dirt and skin flakes, and more importantly, any fleas, flea eggs, or
other skin parasites that might be present. The cat swallows these
along with any loose hair, and they are killed by the strong acid in
the cat's stomach.
The cat's tongue is also important for eating, of course. In nature,
cats use their rough tongues as efficient tools for scraping the
flesh from the bones of their animal prey.
Why did the Tower Of Pisa tilt to one side?
On August 9, 1173, construction began of a beautiful new bell tower
at Campo dei Miracoli (Field of Miracles), Pisa, Italy. By the time
the first meter and a half (five feet) of the base was complete, it
was clear that it was tilting.
Over the next two centuries, construction was halted and restarted
several times. The upper floors of the tower were built askew, in
an attempt to adjust for the tilt. As a result, the tower bends
upward, as if trying to overcome gravity.
The tower's tilt was caused by uneven sinking of its foundation
into sandy, marshy soil. It continued to lean further every year,
until recent excavations and reinforcements were made. Work
continues to ensure that the beloved Leaning Tower will never fall.
How can divers stay in deep water for many hours?
Normally, when a SCUBA diver swims very deep, he or she can only stay
at that depth for a short time before it is necessary to return to the
surface. The deeper the dive, the less time is available at the
bottom, where the high pressure causes nitrogen gas to dissolve in
the diver's blood.
On the way back up, the diver must rise slowly to decompress,
avoiding the dangerous "bends" that result from bubbles forming in
the blood as the nitrogen comes out of solution.
But divers who live in an undersea habitat can swim around at depth
for many hours without needing a lengthy decompression period before
coming out of the water. Because the habitat's air is at the same
pressure as the water at the dive depth, there is no danger of
nitrogen bubbling out of their blood when they end the dive.
What is the longest work of literature in verse?
The world's longest poem is the Mahabharata, an epic containing
100,000 couplets in some 18 books. Composed thousands of years ago
in India, the Mahabharata was recently made into a TV series that
became a smash hit in modern India.
The epic poem describes events that took place around 5,000 BC in a
place called bhaarata. It describes the appearance and adventures of
Lord Krishna, a Hindu diety also known as the eighth incarnation of
Vishnu, preserver of the universe. The climax of the story is a
gigantic battle lasting 18 days.
The Mahabharata is a powerful and important religious, spiritual, and
historical document that contains many of the most fundamental
concepts of modern Hinduism. It continues to have a profound effect
on Hindu philosophy and culture.
Where is the longest known underground river?
The longest known underground river was recently discovered in the
remote mountains of Vietnam. It's the Son Trach River, which runs
underground for an astonishing seven miles (11 km) through a gigantic
cave called Hang Khe Rhy (Grass Stream Cave).
The expedition that discovered and partially mapped the Son Trach
River spent twelve days underground, plunging through ice-cold
rushing water and painstakingly mapping every curve and grotto they
found.
Son Trach River and Hang Khe Rhy cave form part of the Phong Nha
massif, a geological unit that contains some of the world's most
spectacular karst limestone formations. The caves, passages, and
above-ground formations in karst areas are formed by the action of
water, which dissolves parts of the rock while leaving other parts
behind.
Why do meteors sometimes come in 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.
What's the smallest graffiti in the world?
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.
What minerals are like molecular sponges?
Minerals in the group called zeolites have unusual crystal structures
that contain many nanoscopic (molecule-sized) holes or channels.
Many zeolites have channels large enough to admit molecules like
water or ammonia. Some of these are useful as "molecular sponges" to
soak up various substances, which become trapped in the channels.
Zeolites are silicate (SiO4) minerals that also contain aluminate
ions (AlO4). The silicate and aluminate ions form cage-like
structures that surround and define the pores. Most natural zeolite
crystals form within cavities in volcanic rock.
There are about 45 natural zeolite minerals, and more than a hundred
synthetic zeolite compounds, with more being discovered all the time.
What's the oldest known Egyptian papyrus?
It has been called "the oldest book in the world." The Prisse
Papyrus, written before 2000 BC, is the oldest papyrus document ever
discovered. It contains portions of two even older works, one of
which is from the third dynasty (3800 BC).
The Prisse Papyrus is named after Prisse d'Avennes, the French
Egyptologist who discovered it. It is a copy of a work written by
Ptah-Hotep, Grand Vizier under the Pharaoh Isesi, who titled it "The
Instructions of Ptah-Hotep." It appears to be a book of advice for
young Egyptian men.
Ptahhotep encouraged honesty, gentleness, and directness. He offered
advice for dealing with supervisors ("Let thy mind be deep and thy
speech scanty") and wives ("Be silent, for it is a better gift than
flowers"). His work influenced later writings for thousands of
years, and echoes of it appear in the Christian Bible.
Why are pretzels shaped like knots?
Traditionally, pretzels are made out of long strips of dough
folded over into a loose, trefoil knot before being baked. They
have been shaped this way since the seventh century. Thought to
bring good luck and prosperity, pretzels have been called the
world's oldest snack food.
Invented by monks, pretzels carry deep, religious meanings. The
folded strips of dough resemble the folded arms of someone who is
praying in the usual manner in those days, while the three holes
represent the Christian Holy Trinity.
In medieval times, pretzels were given to children as rewards for
learning their prayers. Today, they have lost the religious
meanings, but pretzels are still among the world's most popular
snacks.
How many active languages are there in the world?
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.
What expensive seafood was once used as 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.
Who was first to recognize Saturn's rings?
Although Galileo Galilei was the first to see the rings of Saturn,
his telescope did not provide a very good view and he did not
correctly interpret them. He thought he was seeing two smaller
planets just touching the central planet. When the rings became
edge-on to Earth, Galileo was confused by the sudden disappearance of
the two "side planets."
For many years, Saturn was a mystery. The strange side
protruberances came to be called ansae (handles), but no one could
explain what they were, or why they sometimes disappeared.
The first correct interpretation of Saturn's rings was by the Dutch
astronomer Christiaan Huygens [KRIS-chan HOW-kenz] in 1656. For some
time, Huygens kept his discovery a secret, while he finished other
projects. Finally, in 1658 he revealed the secret, then explained it
more fully in his 1659 book, "Systema Saturnium."
Who built the first self-propelled car?
In 1769, the French military engineer Nicholas Cugnot built the first
self-propelled car, a gigantic steam-driven device to pull field
artillery. The three-wheeled vehicle could go a whopping four
kilometers an hour (about 2.5 mph) while carrying a cannon and four
people.
In 1784, William Murdoch built a lighter, faster car using a Watt steam
condenser engine, but the engine was large and it was not very powerful.
In 1802, Trevithick and Evans built a car using a high-pressure steam
engine, but it was also not a success.
It was not until 1804, when Trevithick put one of his steam engines
into a railroad car, that steam transportation became practical. Steam
engines then quickly replaced the horses that were used to pull railway
carriages.
What's the slowest motorized vehicle?
The slowest motorized vehicles are the two Crawler-Transporters,
tractor-treaded monsters that carry the Mobile Launcher Platforms
(MLP), delivering giant spacecraft to the launch pads at the Kennedy
Space Center in Florida. Each weighs 2,721 metric tons (6 million
pounds).
A Crawler-Transporter travels at a maximum speed of 3.2 kilometers (2
miles) per hour, a comfortable walking speed. It moves on a gravel
track called the crawlerway, carrying spacecraft from the Vehicle
Assembly Building to Launch Pad A or Launch Pad B.
When the Crawler reaches the launch pad, it sets the Mobile Launcher
Platform down on special pedestals. The MLP remains in place during
the launch. Just before ignition, thousands of gallons of water spew
out from nozzles on the MLP. The water absorbs some of the intense
sound of the rockets, protecting the payload of the spacecraft.
How do clownfish avoid the stings of anemones?
Colorful clownfish live among the deadly tentacles of sea anemones.
Unlike other fish, which are quickly stung to death and eaten by the
anemones, the clownfish are not harmed even when they snuggle deep
into the tentacles.
From their very first minutes of life, the clownfish cover themselves
with a special mucus coating made of a combination of their own
secretions and the secretions of the anemone's tentacles. Because
they are covered with this coating, they are protected, just as the
tentacles are protected from their own stings.
Clownfish live in a symbiotic (mutually beneficial) relationship with
the anemones. The clownfish are protected from predators, while the
anemones are kept clean and protected from fish that eat their
tentacles.
What's the tallest island on Earth?
The tallest island is New Guinea, in the southwest Pacific just north
of Australia. Its highest point is the top of Mount Djaja, at 5030
meters (16,503 feet). New Guinea wins the title hands down, towering
825 meters above the next tallest island, Hawaii.
New Guinea is not only the world's tallest island, it is also the
second largest (Greenland is larger), measuring 885,780 square
kilometers (342,000 square miles). It is mostly covered with lush
tropical rainforest containing almost 9000 species of plants and 700
species of birds.
New Guinea also is the most linguistically diverse area on Earth.
Over 700 languages are still spoken by the native Melanesians,
Papuans, and Negritos. In some remote sections of the interior,
headhunting and cannibalism are still practiced.
How do transgenic crops resist pests and weed killers?
Have you heard about the new transgenic crops? Some of them can
resist weed killing chemicals, and some are resistant to insect
pests. The secret of transgenic crops is that they contain genes
taken from other life forms.
For example, a new kind of corn contains a gene taken from
bacterium that normally lives inside insects, killing them. The
bacterial gene creates a protein that poisons the insects, and
when it is present in the corn plant it creates the same protein,
which kills any insects that try to eat it.
Transgenic crops are being tested all around the world, but many
people are worried about the results. There are several ways that
growing such crops might lead to ecological problems, and no one
knows what the real risks are.
What mineral was used for oven window panes?
The mineral muscovite, a kind of mica, forms thin, durable, flexible
sheets when its crystals are cleaved (broken apart along natural
surfaces called cleavage planes). Since these sheets are not only
transparent, but also resistant to great heat, sheets of natural
muscovite mica were once used as window panes for ovens.
Muscovite crystals have alternating layers of aluminum silicate and
potassium ions. The one-atom-thick layers of potassium ions are very
easy to break apart, while the aluminosilicate layers are tightly
bonded together. As a result, extremely thin sheets of muscovite can
be easily separated, yet these thin sheets are flexible and tough.
The mica group includes not only transparent muscovite, but also
black biotite, pink lepidolite, green fuchsite, and about twenty
other minerals, all of which share the same flat, thin, sheetlike
crystal form.
