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The sun is a star.  Sunspots are dark because they are cooler.  Mercury is so close to the sun that many astronmers have never seen it.  Like Mercury, Venus lies between Earth and the sun.  For that reason, it never strays far from the sun in the morning or evening skies.  It can be seen in the western sky after sunset.  Venus gets as bright as -4.5 magnitude.  Only the sun and moon are brighter. Venus accompanied by a crescent moon is one of the beautiful sights in nature.  <br /> <br /> Moon, Venus and Jupiter Venus & Jupiter in the west after sunset Earth from space From space, Earth is a blue planet spotted with cloud tops.  The earth is 25,000 miles in circumference and 8,000 miles in diameter.  It revolves around the sun once every 365 days, the period defined as a year.  Northern Lights Northern Lights from Space Shuttle Note the oval shape around the pole. From the moon, the earth is stationary but goes through phases. American astronauts went to the moon 6 times between 1969 and 1972.  12 men walked on its surface.  Neil Armstrong was the first.  Apollo 11 landed in the Sea of Tranquillity.  Eugene Cernan was the last man on the moon.    Charles Duke collects lunar samples. John Young took the picture at the rim of Plum Crater.  <br /> <br /> Moon map Tycho in the south is outstanding. The most obvious features are the dark maria, or seas.  They are lava plains.  Lava flowed from the moon&#39;s interior when the impacts were hard enough.  5 maria combine to form a foot with 3 toes.  The temperature of the moon&#39;s surface varies 500 degrees, from 225 degrees to -275 degrees. Apennine Mountains on the moon Until recently, it was thought that the earth and moon formed at the same time.  It now appears that the moon came into existence when a large asteroid crashed into the earth and ripped part of it away.  Earthshine An eclipse of the moon occurs when the moon passes through the earth&#39;s shadow.  A lunar eclipse always occurs during a full moon.  Usually, the moon passes above or below the earth&#39;s shadow.  I saw my first total lunar eclipse in March, 1960.  The full moon took on a dark, copper color but remained visible because sunlight was refracted onto it by the earth&#39;s atmosphere.   The color of a totally eclipsed Moon depends on conditions in Earth&#39;s atmosphere. The Moon may appear copper, orange or brown.   <br />  <br />  <br /> <br />  <br />  <br /> With a solar eclipse, the moon passes between the sun and the earth.  During an annular (ring) eclipse, a ring of sunlight circles the moon because the moon is at its maximum distance from the earth.  Mars gets its red color from the dust storms that whip around it.  Mars&#39; surface contains iron oxide (rust).  Its polar caps are made of frozen carbon dioxide (dry ice).  The Mars Science Laboratory will be launched in 2009 and land on Mars in 2010.  Jupiter Jupiter is called a failed star.  If it had been a bit larger, nuclear reactions would have begun and it would shine by its own light.  It is made of hydrogen and helium.  Jupiter has bands because it rotates so fast, its clouds get pulled into patterns.  The Great Red Spot is a gigantic storm raging for at least 4 centuries. Jupiter has 60 moons.  The 4 largest are Io, Europa, Ganymede and Callisto, named for Jupiter&#39;s lovers.  They were discovered by Galileo who invented the telescope in 1610.  Io is the most intriguing of the Galilean moons.  It has the only volcanos in the solar system beyond Earth.   Saturn is a butterscotch-colored ball of gas flattened at its poles.  It is so light it would float in water.  Saturn&#39;s rings are its glory.  The rings appear solid but are made of chunks of rock and ice.  There are 7 main rings.  As Saturn travels around the sun in a 29-year orbit, we see the rings open at the top, edge-on, open at the bottom and edge-on again.  Saturn Saturn's Seasons The Cassini spacecraft imaged Saturn from above and below, showing its ring fully surrounding the planet. Saturn&#39;s moon, Titan, is larger than Mercury.  Titan is the only moon in the solar system with an atmosphere.  Its atmosphere is orange and dense.  Uranus was knocked on its side.  Modern astronomy is increasingly explained in terms of collisions.  Uranus was discovered by William Herschel in 1781.  It is as featureless as a green pool ball.  Voyager 2 photographed Neptune&#39;s Great Dark Spot midst blue methane.  Neptune has 11 moons.  Pluto and Charon The small, rocky Pluto on the edge of the solar system breaks the rules.  Its orbit is erratic, bringing it inside Neptune.  It has a companion, Charon.  Clyde Tombaugh discovered Pluto in 1930. New Horizons path To arrive in 2015 I saw comet Ikeya-Seki on Halloween morning, 1965.  It was dim and hazy but worthwhile.   It took 30 years to see my second comet which I spotted the morning of March 24, 1996.  Comet Hyakutake was as bright as The Big Dipper stars and extended its handle.  It was fuzzy but had no discernible tail.  Two mornings later,  Hyakutake had moved by The Little Dipper.  The morning of March 27, it was under the North Star.  The Japanese are comet hunters.    Comets are scraps left over from the formation of the solar system.  They circle the sun.  Comets develop tails as the sun melts ammonia and methane ice.  The tails extend for millions of miles and point away from the sun, driven out by the solar wind.  Perseids The radiant is to the left of Perseus&#39; head and down a bit. I began watching the Perseids meteor shower in 1961.  The Perseids is the best meteor shower and peaks on the night of August 11 and morning of August 12 annually.  In 1964, I counted 351 meteors.  The Perseids are a spin-off of comet Swift-Tuttle.  Meteor Crater near Winslow, Arizona is evidence of a large meteorite or asteroid that fell 50,000 years ago.  200 impact craters have been found around the world.  Museum of Natural History - Washington, D.C. Zodiac Star Dome - April, 2007 Double stars are the rule rather than the exception.  Albireo is at the end of Cygnus the Swan.  The contrast between the blue star and its yellow companion is striking.  Stars form in clusters.  The Pleiades are condensing from surrounding gas, 440 light years away.    Blue hydrogen nebula in Orion. In Cygnus Stars form in clusters.  The Trifid Nebula is a stellar nursery.  Nebulae glow because they reflect starlight.  4 nebulous patches in the constellation Scorpius Horsehead Nebula Horsehead Nebula 2 An open star cluster in the dim constellation Monoceros (Unicorn).   <br /> In the constellation Serpens The Owl Nebula is a planetary nebula in Ursa major. Ring nebula The Helix Nebula is a planetary nebula at the end of a sun-like star&#39;s life. Gas is expelled into space. A helix is a coil.   A dying star becomes a planetary nebula when it gives off a shell of gas.  The Ring Nebula in Lyra is a planetary nebula.  &#34;Planetary nebula&#34; is a bad name beacuse it has nothing to do with planets.  NGC6302 in Ophiuchus In the constellation Taurus Best known nebula The Milky Way is our own galaxy, and we are locked inside it.  The Milky Way consists of 400 billion suns.  It is shaped like a flying saucer.  Our solar system revolves 2/3 of the way from the center toward the rim.  It takes 200 million years for our solar system to revolve around the galaxy.  This is called the cosmic year. Milky Way Milky Way Milky Way Cygnus portion of Milky Way explored by Kepler Spacecraft Milky Way Center of Milky Way Milky Way Milky Way The Magellanic Clouds of the Southern Hemisphere are irregular galaxies.  The are satellites of the Milky Way.  The Andromeda Galaxy M31 is part of the Local Group.  It is a spiral similar to the Milky Way but 50% larger.  It is 2.3 million light-years from us and the fartherest object visible to the naked eye.  It is a faint, hazy patch.  The Sombrero galaxy looks like a work of art.  After the Big Bang, primordial energy and matter began flying in all directions.  It cooled.  Gas clouds condensed into galaxies.  The Sunflower Galaxy is 35 million light years away in Canes Venaciti.  NGC 3184 23 million light years away in the constellation, Canes Venaciti.  The smaller galaxy to the left is behind the Whirlpool.  We know this from the dust from the Whirlpool&#39;s spiral arm in front of it.   <br /> <br />Canes Venaciti are the Hunting Dogs held on a leash by Boötes as he hunts for the bears Ursa Major and Ursa Minor. Canes Major and Minor are Orion&#39;s dogs.   Silver Dollar Galaxy This barred spiral galaxy shows clouds of hydrogen gas glowing in red. Flying Saucer Galaxy NGC 4565 Considered a twin of our Mily Way. William Herschel discovered this edge on galaxy close to Andromeda.  A spiral 11 million light years away in the Big Dipper. Discovered by Johann Bode 1747-1826.  Bode was born in Hamburg, Germany. Galaxies are aggregates of stars.  They are the building blocks of the universe.  There are 100 billion galaxies. Triangulum Galaxy M33 16 million light years from Earth. Pinwheel Galaxy M101 Starburst Galaxy NGC 253 Interacting galaxies in Virgo, also called The Butterfly Galaxies. Discovered in Cepheus by William Herschel. Discovery - July 26, 2005 The sun and earth are seen from the Space Shuttle Endeavour, also the shuttle&#39;s robotic arm.  <br /> <br /> Michael and I got a feeling for the International Space Station at the Kennedy Space Center at Cape Canaveral.  Shuttle missions fly to the ISS.  21 nations are involved.
ASTRONOMY
Jun 1, 2009
I have had 4 rounds of astronomy. Round 1 was as a teenager in the early 1960s. I learned the constellations and watched meteor showers. Round 2 was in my 30s. I got into cosmology, learned the features of the moon & wrote my first astronomy paper. Round 3 was in my 50s. I subscribed to Astronomy Magazine, started this paper & went to Australia for a star party. Round 4 is in my 60s and 70s. I went to a star party in Bolivia and witnessed the Great American Eclipse.

HISTORY
Each period in history sees the sky in a different way. The way a civilization perceives the sky is related to its travel potential. As man's knowledge of geography has increased, so has his understanding of the earth's place in the larger scheme.

Greek astronomer Ptolemy lived in the second century. In his book called the Almagest, he placed the earth at the center with the sun and planets going around it. This view stood 1400 years.

In 1543, Copernicus in Poland got it right. He expounded a heliocentric doctrine. Modern science was born! Copernicus actually revived a forgotten idea of the Greek Aristarchus. The Greeks had science, and the Scientific Revolution which grew out of the Renaissance was a return to Greek ideas. The Church dominated the Middle Ages.

The road leading from superstition and false information was long. For centuries, Europe's concept of reality was shaped by the Bible. Nowhere in the Bible does it state that the earth is flat, but the implications are there: "4 corners of the earth" and Satan taking Jesus to the mountaintop to show him the world's kingdoms. Heaven was above. Hell was below. Even Shakespeare retarded the growth of science with ghosts, witches & fairies. No wonder the people who settled in America knew so little!

Times were changing! Europe was expanding, and the printing press spread new ideas. By the time of Columbus, most people knew the earth was round. It became irrefutable when Magellan sailed around it, a grueling 3-year voyage during which Magellan was killed.

Tycho Brahe was an observer. He saw a supernova in Cassiopeia in 1572. As a theorist, he was a dud. He knew the planets circled the sun but thought both the sun and the planets circled the earth. His observatory was near Hamlet's castle in Denmark.

It took Tycho's assistant, Johannes Kepler, to make sense of Tycho's work. Kepler showed the orbits of planets to be elliptical. The closer planets are to the sun, the faster they move.

William Herschel was the father of stellar astronomy. He built big telescopes and made the first model of the Milky Way, mistakenly placing the solar system at its center.

Isaac Newton and Albert Einstein were physicists who laid the groundwork for modern astronomy. Newton introduced the concept of gravity, the tendency for bodies to attract, whether they are an apple and the earth or the moon and the earth. Einstein gave us relativity. Relativity says the speed of light is the only absolute and that time is relative to the observer.

Even geniuses can be wrong! Newton was an alchemist, and Einstein did not think the universe was expanding. Einstein was born in Germany. He formulated his theory of Special Relativity in 1905, and his theory of General Relativity in 1915. Being Jewish, he emigrated to the United States when the Nazis took over.

Astronomy can be studied as a series of levels proceeding outward. Space has depth, and there are motions within motions. We explore the solar system and reach for the stars. The Milky Way becomes one of countless galaxies. We question the origin and fate of the universe. We search for extraterrestrial life!

SOLAR SYSTEM
The solar system began as a cloud of gas and dust. Gravity caused it to contract into a spinning disk with the sun at its center. Planets formed in the disk. Gravity caused rocky planets to form near the sun with gas giants floating farther out. Celestial bodies are round because they are molded by the effects of spinning. All stars may have planets.

There are 2 kinds of objects: those that shine by their own light like stars and those that reflect light like planets and moons.

The sun is an average star 93 million miles away. Its surface is 11,000 degrees. The sun shines by nuclear fusion. Hydrogen turns into helium, emitting energy in the form of light and heat. Energy is stored in fossil fuels: coal, oil & gas. Sunspots appear dark because they are cooler.

The sun is a middle-age star and will burn another 5 billion years. It will become a red giant. The planets will be consumed. Earth's oceans will boil away, and the sky will turn black.

Mercury is so close to the sun that many astronomers have never seen it. Its surface is cratered like the moon's. And like the moon, it has no atmosphere.

Like Mercury, Venus orbits between the earth and the sun. For this reason, Venus never strays far from the sun in the evening or morning skies. It is seen in the western sky after sunset and goes through phases visible through a small telescope. Venus is brightest in its crescent phase because it is closer to Earth. It gets as bright as -4.5. Venus accompanied by a crescent moon is a beautiful sight.

Venus is about the size of Earth, and we might expect similarities. But the surface of Venus is 900 degrees due to a greenhouse effect. Its atmosphere consists of carbon dioxide and sulfuric acid.

EARTH
From space, Earth is a blue planet with white cloud tops. It is 25,000 miles in circumference and 8000 miles in diameter. Earth orbits the sun every 365 1/4 days, a period we call a year.

Earth is tilted 23 1/2 degrees on its axis, which causes the seasons. Northern and Southern Hemispheres alternately tilt toward and away from the sun. When it is summer in the United States, it is winter in Australia.

Earth's moderate distance from the sun is a factor in the evolution of life. Earth is neither too hot nor too cold, allowing liquid water to exist. Where there is water, there is life! It rained for millions of years to create the oceans.

Earth's orbit varies over millions of years. It stretches to create ice ages.

Earth's magnetic field (magnetosphere) is caused by molten iron at the earth's core. It extends into outer space and protects us from solar radiation and harmful rays from deep space,

Mountains are caused by stresses in the earth. Our atmosphere came from volcanoes and extends 300 miles. It provides protection from deadly rays.

Life began in the sea. 4 billion years ago, chemicals started showing signs of life. Viruses straddled the line between the living and nonliving. One-celled organisms evolved. Plants colonized the land. Plants produced oxygen by photosynthesis, making animal life possible. Invertebrates and vertebrates evolved. Fish evolved into amphibians, which evolved into reptiles. Dinosaurs lived in the Mesozoic Era between 65 and 245 million years ago: tyrannosaurus, brontosaurus, triceratops, stegosaurus, ankylosaurus & duckbills. I wrote a paper called "The Other Sciences," which was dinosaur-based. A species is a group of animals whose members interbreed. There are 10 million species of animals.

The continents formed one land mass called Pangea. As continental drift occurred, reptiles evolved into birds and mammals. Most paleontologists believe that dinosaurs became birds. There was an age of giant mammals in the Cenozoic Era. Mammoths and mastodons became extinct at the end of the recent Ice Age. Man has existed in some form for 5 million years. He evolved from primates in southeast Africa and spread into Europe and Asia. From Asia, he populated the South Pacific islands and walked across the land bridge at the Bering Strait into the Americas. That was 50,000 years ago. Races as we know them came into existence 20,000 years ago at the end of the Ice Age. Civilization was born in Egypt and Mesopotamia. Recorded history spans 5000 years. The colonization of the Americas by Europeans from the Renaissance forward is the most important human migration in history. World population is 7.8 billion with 330 million in the United States.

Natural history is explained in terms of the Geological Time Scale. Paleontologists study the fossil record. Fossils are found in sedimentary rocks laid down by water. Radio carbon dating determines the age of a rock, and knowing the age of a rock is to know the age of its fossils.

Environment
I recall Al Gore's book about the environment. It was unreadable! Bush 41 referred to Gore as "Ozone Man" because of his obsession with the ozone layer. Global warming was a major issue with Gore. It is the tendency for man-made carbon dioxide to trap heat in Earth's atmosphere. The fear is that Earth will be heated to the point that its polar caps will melt, flooding coastal cities. Paradoxically, geologists say we are between ice ages. If another ice age is inevitable, global warming might serve as a means of heating the planet. We are trying to figure out whether we will burn up or freeze to death. If global warming is happening, it may not be so bad. It got pretty cold in Nashville this past winter. If it is bad, man's ingenuity will find a remedy. We are rational beings. With the population of the earth almost 8 billion, we need to manage natural resources. The rain forest of South America cannot be destroyed without repercussions. We should be planting trees, one for each one we cut down. Houses have traditionally been built with lumber, and books have been made of paper. That can change. New building materials can be developed, and libraries can become electronic. The large mammals of Africa need to be protected, otherwise they will be extinct in a few decades. It is up to the governments of African countries and their National Park systems. At the same time, it is a world problem. Man is one species despite his fragmentation into religions and nationalities. If man were to act as one species (I am not promoting a one-race concept) and stop warring, he could put his house in order. Money spent by Muslims, Jews & Christians fighting each other could go a long way toward developing alternative fuels. Fossil fuels will eventually be depleted. It will take time, but the amount of coal, oil & gas is finite. If man does not prepare for a time when they are gone, civilization may collapse. For all the talk about renewable energy and hybrid cars, we are nowhere near a state of practical application.

MOON
In 1981, I used maps to identify the moon's prominent features. The dark maria are lava plains. Lava flowed from the moon's interior when the impacts were hard enough. 5 maria combine to form a foot with 3 toes: Tranquillity, Serenity, Crises, Fertility & Nectar.

There are not many maria on the far side of the moon. The crust is thicker, so it did not break and flood the lowlands.

The moon is geologically dead. If a meteor hits, the crater is more or less permanent. There are some interesting craters. Aristarchus is the brightest. Plato is the darkest. Copernicus, Aristarchus, Kepler & Grimaldi form a Y. Tycho in the south is the youngest crater. Young craters have rays extending from them. Rays are stuff that was thrown out. Craters have central peaks, caused by the ground bouncing back. The Apennine mountains rise 20,000 feet.

Earthshine is Earth lighting the lunar night. It is sunlight reflected by Earth, hitting the moon and bouncing back to our eyes. Earthshine is seen during the moon's crescent phases when the moon is almost in line with Earth and the sun. The horns of the moon always point away from the sun.

The moon appears to wax and wane in its monthly orbit. Its phases are new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter & waning crescent. A new moon is "no moon" because the side reflecting sunlight is turned away from us.

First quarter is lit on the right. Last quarter is lit on the left. Quarter phases mean a quarter of the cycle, 90 degrees from the sun in either direction.

A blue moon is a second full moon in a calendar month. Blue moons occur once every 2.7 years.

Until recently, it was thought that the earth and moon formed at the same time. It now appears that the moon came into existence when a planet-size object crashed into the earth and ripped part of it away. This accounts for the moon not having a metal core. Old theories are earth-based. New theories are space-based.

The earth slowed the moon's spin until it keeps one side toward us. The moon experiences 2 weeks of daylight and 2 weeks of night. There is no such thing as a dark side because the side we never see gets 2 weeks of sunlight each month.

The moon is 240,000 miles from Earth. At our doorstep! If we flew around the world 10 times, we could be on the moon.

The moon causes the tides in our oceans. It tugs on our atmosphere as well, but we are so deep in our atmosphere that we are unaware of it.

I saw a total lunar eclipse in March, 1960. The moon took on a copperish hue. It remained visible because our atmosphere bent (refracted) sunlight onto it.

Earth casts a shadow into space. Lunar eclipses occur when the moon passes into the earth's shadow. This happens during a full moon when the earth, moon & sun line up. Usually, the moon passes above or below the shadow.

Earth's shadow has 2 parts. The umbra is the dark inner cone. The penumbra is the lighter area around it. During totality, the moon is completely inside the umbra. "Umbra" is Latin for shadow.

I saw a partial solar eclipse in February, 1979. It was subtle! Had I not known it was going on, I would not have suspected anything.

During a solar eclipse, the moon passes between the sun and the earth. It covers the sun's disk. Solar eclipses are more fleeting than lunar eclipses because the moon's shadow is smaller than the earth's shadow.

Our sky is blue because our atmosphere scatters short blue lightwaves. The sky on the moon is black because there is no air. The only color on the moon is the blue earth. From the moon, the earth is stationary but goes through phases. The temperature on the moon varies 500 degrees from 225 to -275.

Minerals in the moon rocks vary somewhat from those on Earth. There are no fossils in the moon rocks. Life began in the sea, and the moon has no water.

American astronauts went to the moon 6 times between 1969 and 1972. 12 men walked on its surface. Neil Armstrong was the first. He made a mistake when he delivered his prepared statement, saying, "One small step for man, one giant leap for mankind." What he meant to say was, "One small step for A man." Apollo 11 landed in the Sea of Tranquillity.

Weirdos claim the moon landings were fake. They point to the picture of the American flag supposedly blowing in the wind. Of course, there is no wind on the moon. A horizontal rod was attached to the top of the flag to keep it from going limp. I am not sure if these people are crazy, stupid or making a joke. I debated Bart Sibrel in the parking lot of a karaoke bar in Nashville. He was convinced that men never went to the moon. It came out in the news that he approached Buzz Aldrin (second man on the moon) in California and tried to force him to swear on a Bible that the moon landings were real. Buzz punched him in the jaw! Bart tried to sue, but the Los Angeles County District Attorney refused to file charges.

OUTER PLANETS
MARS
The outer planets display retrograde motion. They appear to travel backwards as the faster Earth overtakes and passes them. Mars is the best example.

Percival Lowell studied Mars from his observatory in Flagstaff, Arizona. He saw what he thought were canals built by Martians.

Mars gets its redness from dust storms. Its surface contains rust (iron oxide). The polar caps are dry ice (frozen carbon dioxide). Mars has a huge volcano called Olympus Mons and a canyon called Valles Marineris.

Mars' atmosphere is too thin for water, although there is evidence that water once flowed. The surest way to know if life evolved is to go there, bring back rocks and check them for fossils. A journey to Mars will take 7 months.

The Viking spacecraft landed on Mars in 1976. It found chemicals said to mimic life. The essentials for life are water, nutrients & energy. Scientists study the Atacama desert in Chile, the driest place on Earth, to learn about Mars.

Curiosity landed on Mars in August, 2012, trying to determine whether microbes evolved. There may have been a zone of life in the early solar system extending from Venus to the asteroids.

Phobos and Deimos are Martian moons. They were Fear and Panic, sons of the god of war, in Homer's Iliad.

The asteroid belt lies between Mars and Jupiter. Jupiter's influence kept these rocks from coalescing into a planet.

Difference in mass means a difference in gravity. Large worlds like Earth and Venus hold atmospheres. Small worlds like the moon and Mercury do not. Medium-size Mars holds a thin atmosphere. Worlds with atmospheres have less craters because atmospheres vaporize meteors and cause erosion. Earth has a few craters. Mars has more. The moon and Mercury are covered with them.

GAS GIANTS
Voyager 1 flew by Jupiter and Saturn. Voyager 2 went on to Uranus and Neptune. Voyager 2 spent 12 years (1977-89) on a Grand Tour. All the gas giants have rings.

Jupiter is called a failed star. If it were larger, nuclear reactions would have begun, and it would shine by its own light. It is made of hydrogen and helium, the most common elements.

Jupiter has bands because it rotates so fast. Clouds get stretched into patterns. The Great Red Spot is a storm. The Galileo probe reached Jupiter in 1995.

Jupiter has 79 moons. Io, Europa, Ganymede & Callisto are the largest, named for Jupiter's lovers. Galileo saw them through his telescope in 1610. Io has the only volcanoes in the solar system beyond Earth.

Saturn is a ball of gas light enough to float in water. Its rings are made of ice and rock. As Saturn orbits the sun every 29 years, we see the rings open at the top, edge-on, open at the bottom & edge-on again.

The Cassini spacecraft imaged Saturn from above, showing it surrounded by rings. Giovanni Cassini discovered the gap.

Saturn has 82 moons. Titan is the only moon in our solar system with an atmosphere.

William Herschel discovered Uranus in 1781. Uranus was knocked on its side! Modern astronomy is increasingly explained in terms of impacts. Consider that the dinosaurs were killed by an asteroid. If the ancients thought the heavens benign, today's universe is a violent place.

Johann Galle, a German, discovered Neptune in 1846. Voyager 2 imaged its Great Dark Spot against blue methane.

Small, rocky Pluto is erratic. Its orbit takes it inside Neptune's. Clyde Tombaugh discovered Pluto in 1930. The New Horizons spacecraft reached Pluto in 2015, at a distance of 3 billion miles. There are 5 moons: Charon, Nix, Hydra, Styx & Kerberus.

The Kuiper Belt (pronounced like viper) lies beyond Pluto. Kuiper Belt Objects are small, icy objects similar to Pluto.

The Voyagers left the solar system and are headed for the stars. They contain recordings of our languages and music.

The solar system and everything in it is 4.6 billion years old. This includes the sun, planets, moons, comets, meteors & asteroids.

COMETS, METEORS & ASTEROIDS
Comets are scraps left over from the formation of the solar system. There was a lot of debris and massive craterization. Comets orbit the sun. They develop tails when the sun melts ammonia and methane. Tails are millions of miles long and point away from the sun, pushed out by the solar wind. Halley's comet orbits beyond Neptune, returning every 75 years. Halley was not the first to see the comet but the first to predict its return.

I saw Comet Ikeya-Seki on Halloween morning, 1965. It was fuzzy and dim. I saw Hyakutake in 1996 and Hale-Bopp in 1997.

It took 30 years to see my second comet, which I spotted the morning of March 24, 1996. Hyakutake was as bright as the Big Dipper stars and extended its handle. It was hazy with no discernible tail. Two mornings later, it was close to the Little Dipper. The morning of March 27, it was below the North Star. Hyakutake upstaged the highly-publicized Hale-Bopp.

Shoemaker-Levy 9's impact with Jupiter gave astronomers their first glimpse of a collision in space. Jupiter is a vacuum cleaner, sucking up stuff and protecting Earth.

I began watching the Perseids in the early 1960s. The Perseids are in August. It is the best meteor shower, and I counted 351 the night of August 11 and morning of August 12, 1964. Toward morning, they were dropping in the east like snowflakes. Many were bolides, leaving bright trails! The best one appeared after daybreak. My cousin was yelling, and I looked up to see a meteor the size of a half moon!

Meteor showers are associated with comets, and the Perseids are associated with Swift-Tuttle. As Swift-Tuttle orbits the sun, it leaves behind debris. Meteoroids string out along its path. Most of the meteors entering our atmosphere are like grains of sand vaporized by friction a hundred miles up. In a shower, meteors emanate from a point called the radiant. Showers are named for the constellations behind their radiants. We see more Perseids toward morning because we meet them head-on.

Meteorites are objects that survive and fall to earth. They are made of iron and nickel. Meteor Crater near Winslow, Arizona, is evidence of a large meteorite which impacted Earth 50,000 years ago.

128 impact craters have been found around the world. The largest meteorite found in the United States came from Willamette, Oregon. I saw it in the American Museum of Natural History in New York. O. Richard Norton said meteorites are pieces of asteroids.

There is one case of a person being hit by a meteorite. In 1954, a woman in Alabama was sleeping on her couch when a meteorite crashed through her roof. It ricocheted and hit her in the side.

The idea that the dinosaurs were killed by an asteroid is accepted. Asteroids make craters. Scientists point to Chicxulub (Cheek-shoe-lube) crater in Mexico's Yucatan as the impact that killed the dinosaurs and two-thirds of all species. Evolution is driven by impacts.

A comet hit Siberia in 1908, referred to as the Tunguska Event. Trees were flattened, but no crater was found. The comet vaporized before impact.

Earth's atmosphere is like sandpaper, smoothing out craters. Water erodes, and plate tectonics reshape the planet. Otherwise, the earth would look like the moon.

STARS
Stars are always there, even in the daytime when they are washed out by sunlight. This is something children may not understand. As the earth revolves in its orbit, different parts of the stellar panorama are exposed in the night sky. Constellations become identified with seasons.

Constellations are illusions. They are 2 dimensional. They existed in the minds of ancient Greeks. The stars are 3 dimensional and at various distances. Some appear bright because they are close. Others appear dim because they are far away.

The most famous constellations are Ursa Major (Big Dipper), Orion & Scorpius. The pointers in the bowl of the Big Dipper point to the North Star. Polaris is overhead at the North Pole and maintains its position as the earth spins. It is slightly off. Over 26,000 years, the earth wobbles like a top, causing precession of the equinoxes and a shift away from Polaris as the North Star.

The Zodiac consists of Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius & Pisces. The sun, moon & planets appear against the background of the Zodiac because of the flatness of the solar system. Everything is in the same plane.

Constellations are tied to Greek and Roman mythology. The most elaborate story is that of Perseus and Andromeda, told by the fall constellations. There are Andromeda's parents, Cepheus and Cassiopeia, and the monster Cetus. Perseus holds the head of Medusa, represented by the variable star Algol. Pegasus is the winged horse ridden by Perseus.

The stars forming our constellations are in the local star cloud and near the sun when we think in terms of the Milky Way. The Greeks explained the Milky Way in poetic fashion. Legend had it that Hercules was born from an affair between Zeus and a mortal. When Zeus wanted his wife, Hera, to suckle the baby, she pushed it away and her milk flowed across the sky.

Visible stars range from 1st to 6th magnitude. The brightest are Sirius, Canopus, Alpha Centauri & Arcturus. Arabs named the stars. Stars twinkle because our atmosphere bends their light. They are so far away that they appear as points of light even through large telescopes. We see 4000 at any one time.

Stars are trillions of miles away, and their distances are measured in light-years. A light-year is the distance light travels in one year: 6 trillion miles. Light is the fastest thing in the universe at 186,000 miles per second. The closest star is Alpha Centauri, 4.4 light-years or 25 trillion miles away.

Double stars are the rule. Mizar, the second star in the handle of the Big Dipper, is a double. So is Albireo at the head of Cygnus. The contrast between its yellow and blue components is striking.

Astronomers compare stars to people. Stars are born. They age. They die. Stars are born when gaseous nebulas shrink under their own gravity. Mass determines whether a celestial body will become a star. If there is enough mass, pressure and temperature at the core will start nuclear reactions.

Stars form in clusters. The Orion Nebula is a stellar nursery. Nebulas glow when they reflect starlight. The Pleiades are condensing from surrounding gas. The Horsehead Nebula is dark, outlined by the starlight behind it.

Stars come in colors. Blue-white stars are young and hot. Yellow stars like the sun are in the mid-temperature range. Red giants are old and cool.

Stars die in 2 ways. Average stars like the sun become red giants. They die peacefully by exhausting their fuel. Antares and Betelgeuse are red giants.

After a star burns all of its hydrogen, it burns helium to make carbon and oxygen. Elements are manufactured inside stars. Our bodies are made from the remnants of ancient stars.

A dying star giving off a shell of gas is called a "planetary nebula." It is a bad name because it has nothing to do with planets. A dying star shrinks to become a white dwarf. The Ring Nebula is a dying star.

Massive stars die by becoming supernovas and blowing themselves up. Supernovas may become neutron stars, pulsars or black holes. Black holes are collapsed stars whose gravity is so great that light cannot escape. A supernova occurred in the Large Magellanic Cloud in 1987.

MILKY WAY
The Milky Way is our Galaxy, and we are inside it. This is not apparent right away as we gaze at the glimmering arch across the night sky. The Greeks saw milk! But the Milky Way consists of 400 billion suns 100,000 light years across and 2000 light-years thick. If we could step outside the Milky Way, we would see a disk with a bulging center, shaped like a flying saucer. Our solar system revolves two-thirds of the way from the center toward the outer rim. It takes 240 million years to revolve around the Galaxy, a period known as a cosmic year. In the desert in 1979, there was a moment when I sensed myself revolving around the galactic center.

Because we are in our Galaxy, figuring out its shape is like someone in a house trying to determine the shape of the house. The structure of the Milky Way and the sun's position in it was ascertained by Harlow Shapley in 1917. We see it when we know what we are looking at. The Milky Way circles the sky, and its bulging center lies in the direction of Sagittarius, where the star clouds are thick. The thin part of the circle is visible in winter and lies in the direction of Orion. When we look at right angles to the Milky Way, we look out the top or bottom of the disk, where stars are sparse. As we might expect, more galaxies can be seen out the top or bottom.

Patches of gas and dust like the Coalsack and Cygnus Rift obscure parts of the Milky Way. People once thought these were holes. Because of gas and dust, we use radio telescopes to study the center of the Galaxy. The Milky Way is 10 billion years old.

COSMOLOGY
The universe is 13.8 billion years old. 13.8 billion years ago, all the stuff in the universe was concentrated in a singularity, a speck of infinite density. It expanded, and this is what we call the Big Bang, the point at which space/time began.

Energy and matter flew in all directions. Things cooled, and gas clouds condensed into galaxies. Galaxies are aggregates of stars, the building blocks of the universe. There are billions of galaxies. Some are distinctive. The Whirlpool and Sombrero look like works of art! Galaxies are categorized according to structure. The Milky Way is a spiral. M87 is an elliptical. The Magellanic Clouds are irregular.

The Milky Way belongs to a Local Group of 54 galaxies. The Andromeda Galaxy M31 is in this group. M31 is a spiral similar to the Milky Way, but larger. It is 2.5 million light-years away and the furtherest object visible to the naked eye.

Charles Messier assigned numbers to fuzzy objects in the sky. He cataloged 110 so he would not mistake them for comets. He lumped nebulas and galaxies together. The more thorough New General Catalog (NGC) dates from the 19th century.

Galaxies form in clusters, which make up superclusters. The Virgo supercluster is vast. The Local Group is in the Virgo supercluster.

Proof of the Big Bang was provided by Edwin Powell Hubble. By applying the Doppler effect to light, Hubble found that light from galaxies showed a red shift. This suggested that the galaxies were receding, moving away from each other. This is what we mean by the expanding universe. If we run it backwards, there is a point at which all the galaxies converge. Moreover, the further apart galaxies are, the faster they travel. The question becomes whether the expansion will continue forever or whether there is enough gravity to pull things back together. This would be the Big Crunch and suggests an oscillating universe, one that alternately expands and contracts. The universe is not expanding in space. Space itself is expanding. The balloon analogy is used, blowing up a balloon with dots on it.

We ask what was before the Big Bang. The answer is nothing! There was no space/time and no events. This was the beginning in the truest sense.

E. P. Hubble was the greatest astronomer of the 20th century. Shapley thought external galaxies were inside the Milky Way.

Cosmology was the step I was trying to take since I was a teenager. Carl Sagan's Cosmos was a breakthrough. To quote Sagan, "The Cosmos is everything that has been, everything that is and everything that will be." The terms "cosmos" and "universe" are interchangeable.

TELESCOPES
For "Swim With Dolphins," I wrote, "I wanna see the stars, Mauna Kea's calling me." On September 13, 2003, I stood atop the extinct volcano 13,750 feet above sea level. "This is beautiful!" I thought. The volcano was stark and brownish, barren of vegetation. There was a Mars-like surrealism. I watched the sun set over the clouds. Stars blazed! The Milky Way, the plane of our Galaxy, arched overhead. I was on the Big Island of Hawaii in the middle of the Pacific Ocean. It gets no better than this! Hawaii is at 20 degrees north latitude, and the North Star appears lower and Scorpius higher than from Kentucky, although not as high as from Australia, where it gets straight up. I sensed the curvature of the earth! Mars was at its closest, and I wondered why it was less red than when it is farther out. Our guide said increased sunlight hitting the surface neutralizes the redness. The moon rose! I like astronomy and saw a bit of everything. 13 telescopes dotted the summit of Mauna Kea. There were the Keck domes and the Japanese Subaru. "Subaru" is Japanese for the Pleiades. Mauna Kea is run by the University of Hawaii and the largest observatory I have seen. I was above 40% of the atmosphere's oxygen, but felt no different. It misted on the drive up, and rainbows were everywhere.

There are 2 kinds of telescopes: refractors and reflectors. The purpose of each is to gather light. A refractor uses an object lens. A reflector uses a mirror. Reflectors are the biggest telescopes.

Photography revolutionized astronomy. The pictures we see in books are long-exposure photographs.

The Hubble Space Telescope was put into orbit by the Space Shuttle. Because it is above the atmosphere, its pictures are superior to those of earth-based telescopes. I was initially mystified by the HST. It produced chaotic images with no theoretical breakthroughs.

Planetariums put on sky shows. Star patterns are projected inside a dome. I have been to planetariums in Louisville, Nashville, Salt Lake City & New York.

SPACE TRAVEL
The Soviet Union kicked off the Space Age in 1957 with Sputnik. The United States answered with NASA (National Aeronautics & Space Agency).

The Mercury astronauts were John Glenn, Gus Grissom, Alan Shepard, Wally Schirra, Deke Slayton, Scott Carpenter & Gordon Cooper. John Glenn got a hero's welcome after orbiting the earth 3 times.

Saturn 5 rockets sent men to the moon. Apollo 11 was the first landing. Buzz Aldrin's boot print will last millions of years. Aldrin was second on the moon. Apollo 13 was brought back when an oxygen tank exploded. I was on my way to Germany. The 12 Apollo astronauts who walked on the moon are:

Apollo 11 - Neil Armstrong, Buzz Aldrin
Apollo 12 - Charles Conrad, Alan Bean
Apollo 14 - Alan Shepard, Edgar Mitchell
Apollo 15 - Dave Scott, James Irwin
Apollo 16 - John Young, Charles Duke
Apollo 17 - Harrison Schmitt, Eugene Cernan

The Apollo program was followed by a golden age of planetary exploration. Unmanned spacecraft were sent. NASA worked with the Jet Propulsion Laboratory.

Competition between the United States and Soviet Union drove the Apollo program. The spirit of cooperation which is supposed to put men on Mars has proven less of a motivator.

Space shuttles orbited 200 miles up while circling the globe in 90 minutes. Women were the most famous to fly in the shuttles: Sally Ride and the ill-fated Christa McAuliffe. Challenger and Columbia blew up! The shuttles were retired after 30 years.

21 nations are involved in the International Space Station. Michael and I got a feeling for it at the Kennedy Space Center at Cape Canaveral. The Orion spacecraft will take crews to the ISS.

Men will go to Mars during opposition. Mars is closest then at 35 million miles. It will be more challenging than the moon, 150 times farther. Futurists have wild imaginations! They foresee mining the moon and terraforming Mars.

Congress is skeptical of SETI (Search for Extraterrestrial Intelligence), although interest remains. Estimates of the number of alien civilizations range from zero to a certainty that the universe is teeming with life.

Astronomers began finding exoplanets in 1995. 4100 exoplanets have been confirmed. Geoff Marcy searches for Earth's twin. Most exoplanets found so far are gas giants like Jupiter, unlikely candidates for harboring life.

The assumption that life began in the sea is questioned in the Space Age. It may be that Earth was seeded from space. Seeds of life may have traveled through interstellar space to take root in the favorable conditions on Earth. This is the Panspermia idea.

Spores are among the hardiest forms of life. They may travel to planets via meteors and comets. They are less likely to travel through interstellar space, but we cannot rule it out. Perceptions are evolving as we reach into space.

UFO sightings, close encounters & abduction stories are bogus. Such phenomena are explainable as airplanes and balloons, Venus and Jupiter, science fiction, psychiatric cases, hoaxes & lies. Roswell is a hoax! Claims that the government conceals UFO information are absurd.

PHYSICS
Energy is the ability to do work.

The 4 forces in nature are gravity, electromagnetism & the strong and weak nuclear fields. Gravity is the weakest but long-range. The strong nuclear field binds protons and neutrons. The weak nuclear field is associated with radioactive decay.

Einstein overturned Newtonian physics when he debunked the idea that objects attract. He showed that mass bends, curves & distorts space. The effect of this bending is what we call gravity. The analogy of a trampoline, bowling ball & a marble is used. The bowling ball on the trampoline bends it. The marble moves toward the ball and orbits it if the movement is right.

Einstein showed that space and time are connected. Gravity is the effect of mass bending space/time. The sun and the earth bend space/time.

Space is a fabric in which everything is embedded. It has 3 dimensions: length, width & height. Objects move up and down, forward and backward, side to side & through time. Time is the 4th dimension, being a direction in which things travel.

WEIRD
The more exotic ideas seem like something from Star Wars. Dark matter is said to account for 70% of the mass of the universe. We cannot see it, nor can it be detected. There is also the mysterious dark energy.

Wormholes may be tunnels leading to parallel universes. An infinite number of universes may make up a multiverse, each universe having its own Big Bang.

SCIENCE VS RELIGION
Science and religion have clashed ever since Galileo turned his telescope toward the sky.

According to the Bible, the Virgin Mary got pregnant without Joseph's sperm. An egg fertilized by Spirit? The story goes that an angel informed Mary's husband of her pregnancy. Are we to believe that angels exist or regard them as part of ancient Jewish mythology?

Billy Graham believed in demons. I have never seen one. Nor have I seen a miracle. The Bible is a string of impossibilities! Some people say these things happened back then, but do not happen today.

The Star of Bethlehem! Chances are it was a literary star with no counterpart in nature. Someone is always trying to prove it was a comet or a conjunction of planets.

As for sin, it does not exist in nature. A cat kills a mouse. No sin!

If Jesus is God, when will he return? If the earth is 4.6 billion years old, will he linger another 4.6 billion years?

Can we believe Jesus ascended into heaven? Floated into space? In film biographies of Jesus, he has those piercing blue eyes. The Anglo-Saxon Jesus! He reels off parables that sound like riddles to the modern ear. The surest way to confuse is to use a parable, metaphor, simile or an analogy. What is God? Where is God? Theology must be man's invention! Books and movies take things out of context, thereby reducing life to episodes with hopes of commercial success. The Bible does it. Why do we have to purchase Bibles to know the word of God? Why do preachers condemn money, then beg for it?

We live in a natural universe! Jesus raised Lazarus from the dead in our imaginations. Faith cannot make the impossible happen. Those who speak of an "empty tomb" fail to distinguish between a real tomb and a tomb of the mind.

Preachers wear suits and give the appearance of being rational. When they speak of a rapture and rising through the atmosphere, we have to wonder.

Evangelist Jimmy Swaggart extolled the virtuous life while patronizing prostitutes. To me, morality is more probable within a scientific context. Physicists do not use nuclear energy to make bombs. Military establishments with long religious traditions do that.

Mormons are on the edge! They believe Jesus came to the American west to save the Indians. If intelligent life is discovered in another part of the Galaxy, a sect will arise claiming that Jesus redeemed aliens.

The age of theology lay between 3000 B.C. and 600 A.D. Science began just 400 years ago. Carl Sagan regarded science as "the candle in the dark."

If science is the candle, we must put observation ahead of revelation and evolution ahead of creationism. Our eyes tell us how things are! It is what we suspected as kids, before religion clouded our reason. We are physical, not spiritual. We are alive when we are alive, dead when we are dead.

The supernatural does not exist outside of man's imagination. Sagan left us with these words: "Extraordinary claims require extraordinary evidence!" Science is the candle. Not mythology, not astrology, not religion.

Having said all that, I am a Christian! I do not want to go to hell.

SOUTHERN CONSTELLATIONS
We do not see the constellations of the Southern Hemisphere from the United States because the bulge of the earth blocks our view. To see the southern stars, we must journey to or below the equator.

Of the 88 constellations, 32 belong to the Southern Hemisphere. Many were named by Nicolas Lacaille, a Frenchman and the last person to invent constellations.

Animals dominate! There are 2 mammals, 6 birds, 2 reptiles, 2 fish & 1 insect.

..1 Centaurus - centaur
..2 Lupus - wolf
..3 Pavo - peacock
..4 Tucana - toucan
..5 Grus - crane
..6 Apus - bird of paradise
..7 Phoenix - phoenix
..8 Columba - dove
..9 Hydrus - serpent
10 Chamaeleon - chameleon
11 Dorado - swordfish
12 Volans - flying fish
13 Musca - fly

Lacaille added gadgets used by mariners who sailed the south seas in the 16th and 17th centuries. These constellations are abstract and bear no resemblance to what they are supposed to be.

14 Octans - octant
15 Telescopium - telescope
16 Horologium - clock
17 Circinus - compass
18 Antlia - air pump
19 Pictor - painter's easel
20 Norma - carpenter's level
21 Ara - altar
22 Reticulum - net (in an eyepiece)
23 Fornax - furnace
24 Sculptor - sculptor
25 Caelum - chisel

Four constellations made up Argo Navis, the ship on which Jason and the Argonauts sailed.

26 Carina - keel
27 Vela - sail
28 Puppis - stern
29 Pyxis - compass

That leaves:

30 Crux - Southern Cross
31 Indus - Indian
32 Triangulum Australe - southern triangle

The bright stars of the Southern Cross are known as the 3 Marys. According to the gospels, the 3 Marys at the cross were the Virgin Mary, Mary Magdalene & Mary of Bethany, sister of Lazarus. Only Crux and the Beehive Cluster as a manger allude to Christianity.

The Southern Hemisphere has 6 first magnitude stars:

1 Canopus - Carina
2 Alpha Centauri - Centaurus
3 Beta Centauri - Centaurus
4 Acrux - Crux
5 Bcrux - Crux
6 Achernar - Eridanus

STAR PARTIES
(1) On Michael's 18th birthday, March 11, 2002, I flew American Airlines to Los Angeles, then flew Qantas to Sydney, Australia. I crossed the equator and international dateline at about the same place. I got a motel and rode a train to Sydney Harbor. I saw the Opera House, Harbor Bridge & the Rocks (Old Town).

My purpose in going to Australia was to see the southern stars and constellations. Monte Wilson of the Astronomical Society of New South Wales met me at the motel. We drove through the Blue Mountains to Wiruna, 3 hours northwest of Sydney, for the South Pacific Star Party.

I was lucky! The weather was great all 3 nights, and I got to stay in the house, referred to as the "White House" because they let Americans stay there. There was a couple named Tom and Lucy from Texas who proved invaluable. Lucy had lived in Louisville in the Bardstown Road area.

"I saw The Southern Stars burning in their glory!" I saw Canopus, Alpha Centauri & Achernar. I saw the Southern Cross and the Coalsack. I saw the hidden piece of the Milky Way and the Magellanic Clouds. The Clouds are satellites of the Milky Way and fainter than I imagined.

Tom found nebulas and galaxies in Tony Buckley's 20 inch. We looked at Jupiter and Saturn. Scorpius was straight up! The hub of the Milky Way in Sagittarius was high and prominent. I looked into our galaxy's thickest part, something I only saw along the horizon back home. Orion was inverted.

The southern constellations are abstract! To trace even Centaurus would take time. Seeing Scorpius overhead stayed with me, that and seeing Scorpius and Orion in the sky at the same time. I was impressed at how close Canopus was to Sirius and how the Southern Cross was not far from Scorpius.

I will not forget walking out of the house and seeing the southern sky for the first time! It was ablaze with stars! The southern sky is spectacular because we also see the winter stars of the north.

Treasurer Max Gardner drove me back to Sydney. He took me to his home and showed me the city. We crossed the Harbor Bridge, driving on the left side. Sydney is halfway between the equator and the south pole.

Max explained that Australia is a constitutional monarchy and part of the Commonwealth of Nations (British Commonwealth). The queen is head of state.

I arrived in Nashville, March 18, 2002. One week later! Crossing the Pacific Ocean, we came close to Hawaii, and I wondered how long it would be before I saw Hawaii. Noticing a book about Alaska in Max's bookcase, I wondered how long it would be before I saw Alaska.

(2) Karen and I attended the Tennessee Spring Star Party, April 1-2, 2006, at Fall Creek Falls State Park. Frogs croaked hideously as we sat with other stargazers and picked out the spring constellations. A man had his telescope set up and was showing galaxies on a screen. His technology was futuristic! The Whirlpool Galaxy (M51) was like an image in a magazine. We know the small galaxy to the left lies behind the Whirlpool because the dust from the Whirlpool's arm is in front of it. We looked at Bode's Galaxy (M81), a spiral in Ursa Major, and talked about the chances of life elsewhere in the universe.

(3) I went to Alaska for the Northern Lights. I flew to Anchorage and traveled by train to Denali National Park. A full moon interfered with my plans. The Northern Lights are caused by the solar wind hitting gases in the upper atmosphere. Each gas emits a different color. There are green, yellow, red & blue. Green is the most common. The Lights occur around ovals at the poles because the earth is a magnet, pulling particles north and south. We do not hear much about the Southern Lights because the big population centers are in the north. Other planets have Northern and Southern Lights.

(4) Michael and I attended the Grand Canyon Star Party at Yavapai Point, June 9-10, 2007. It was a good time for planets, and the astronomers had their telescopes. We observed Venus, Jupiter & Saturn. Venus blazed as it hung over the Canyon. Although I did not want Michael to get into astronomy because it takes us out of the world, an experience like this was good.


BIBLIOGRAPHY
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Originally written 1995-1996
Revised 2020