I have had four rounds of astronomy. Round one was as a teenager in the early 1960's. I learned the constellations and watched meteor showers. Round two was in my 30's. I got into cosmology, learned the features of the moon and wrote my first astronomy paper. Round three was in my 50's. I subscribed to Astronomy Magazine, started this paper and went to Australia for a Star Party. Round four is in my 60's and 70's. I went to Bolivia and will go where I have to, to see the Great American Eclipse.
Each period in history sees the sky in a different way. The way a civilization perceives the sky is related to its travel capabilities. 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 had the earth at the center with the sun and planets going around it. This view stood 1400 years.
In 1453, 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 false information and superstition was long. For centuries, man'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: "four 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 and fairies. No wonder the people who settled in America knew so little about nature!
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 three-year voyage during which Magellan was killed.
Tycho Brahe was an observer. He found a supernova in Cassiopeia in 1572. As a theorist, he was a dud. He knew the planets circled the sun but thought that both the sun and planets circled the earth. He had an observatory near Hamlet's castle in Denmark.
It took Johannes Kepler, Tycho's assistant, to make sense of his work. Kepler's laws of planetary motion showed their orbits were ellipses. The closer planets are to the sun, the faster they move.
William Herschel was the father of stellar astronomy. He built telescopes and made the first model of the Milky Way. He mistakenly placed 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 two bodies to attract whether they are the earth and an apple or the earth and the moon. Einstein gave us relativity. Relativity says that 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 southern 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 came to power.
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 search for extraterrestrial life! We question the origin and destiny of the universe.
The solar system began as a cloud of gas and dust. It began to spin and contract. It contracted into a disk with the sun at its center. Planets formed in the disk. Gravity caused rocky, terrestrial planets to form near the sun. Gas giants floated further out. Celestial bodies are round because they are molded by the effects of spinning. All stars may have planets.
There are two kinds of objects: those that shine by their own light like the sun 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. Sunspots are dark because they are cooler. The sun shines by nuclear fusion. Hydrogen turns into helium. giving off energy in the form of light and heat. This energy is stored in fossil fuels: coal, oil and gas.
The sun is a middle-age star and will burn another five 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. Mercury's surface is cratered like the moon's. And like the moon, there is no atmosphere.
Like Mercury, Venus is between the earth and the sun. For this reason, Venus never strays far from the sun in the morning or evening skies. It is in the western sky after sunset. It 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, so we might expect similarities. But the surface of Venus is 900 degrees because of a greenhouse effect. Its atmosphere consists of carbon dioxide and sulphuric acid.
From space, Earth is a blue planet with white cloud tops. It is 25,000 miles in circumference and 8,000 miles in diameter. Earth revolves around the sun every 365 days, a period we call a year.
Earth's orbit varies over millions of years. It shrinks and stretches, accounting for ice ages.
Earth is tilted 23 1/2 degrees on its axis. This tilt causes the seasons. Northern and southern hemispheres alternately lean 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. It is neither too hot nor too cold. Liquid water can exist. Where there is water, there is life. It rained for millions of years to create the oceans.
Mountains are caused by stresses in the earth. Our atmosphere came from volcanoes. It provides pressure and protection from deadly rays. It extends 300 miles.
Life began in the sea. Four billion years ago, chemicals began showing signs of life. Viruses straddled the line between the living and nonliving. One-celled organisms evolved. Plants colonized the land. Plants produce oxygen by photosynthesis. Invertebrates and vertebrates evolved. Fish evolved into amphibians, which evolved into reptiles. Dinosaurs lived in the Mesozoic Era between 65 million and 220 million years ago: tyrannosaurus, brontosaurus, stegosaurus, ankylosaurus and duckbills. I wrote a paper called "The Other Sciences," which was dinosaur-based. There are 10 million species of animals. A species is a group of animals whose members interbreed.
The continents formed one land mass called Pangea. As continental drift occurred, reptiles evolved into birds and mammals. Most paleontologists believe that birds are dinosaurs. 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 five million years. He evolved from primates in southeast Africa and spread through 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 5,000 years. The colonization of the Americas by Europeans from the Renaissance forward is the most important human migration in history. World population is over 7 billion with 319 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, those laid down by water. Radio carbon dating determines the age of rocks. To know the age of rocks is to know the age of their fossils.
I recall Al Gore's book about the environment. It was unreadable. George Bush 41 referred to Gore as "Ozone Man" because of his obsession with the ozone layer. Global warming became the big issue with Gore. It is the tendency for man-made carbon dioxide to trap heat in Earth's atmosphere. The fear is that the 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 for heating the planet. It is crazy! We are trying to figure out whether we will burn up or freeze to death. If global warming is taking place, it may not be all bad. It got pretty cold in Nashville last winter. If it is a bad thing, man's ingenuity may find a remedy. We are rational beings. With the population of the earth over seven billion, we need to manage natural resources. The rainforest of South America cannot be destroyed without consequences. We should be planting trees in North America, one for each one 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 religious sects 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. The energy and money spent by Muslims, Jews and Christians fighting 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 and gas in the ground is finite. If man does not prepare for a time when they are gone, civilization will collapse. For all the talk about renewable energy and hybrid cars, we are nowhere near a state of practical application.
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 impacts were hard enough. Five maria combine to form a foot with three toes: Tranquillity, Serenity, Crises, Fertility and Nectar.
There are not many maria on the far side of the moon. The crust on the far side is thicker, so it did not break and flood the lowlands with lava.
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 and Grimaldi form a Y-shape. Tycho in the south is the youngest crater. Young craters have rays extending from them. The 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 up the lunar night. It is sunlight bouncing off the earth, hitting the moon and coming back to our eyes. Earthshine is seen during the moon's crescent phases when the moon is nearly in line with the earth and the sun. The horns of the moon point away from the sun.
The moon appears to wax and wane in its monthly orbit. Phases of the moon are new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter and waning crescent. The 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 are not that rare. They 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 two weeks of daylight and two weeks of night. There is no such thing as a "dark side" because the side we never see gets two weeks of light each month.
The moon is 240,000 miles from Earth. At our doorstep! If we drove around the world 10 times, we could be on the moon.
The moon causes the tides in our oceans. It tugs at our atmosphere as well, but we are so deep in the atmosphere that we are unaware of it.
In March, 1960, I saw a total lunar eclipse. The moon took on a dark, copperish hue. It remained visible because the earth's atmosphere bent, or refracted, sunlight onto it.
The earth casts a shadow into space. Lunar eclipses occur when the moon passes through this shadow. Usually, the moon passes above or below the shadow. A lunar eclipse can only occur during a full moon when the moon, earth and sun line up.
Earth's shadow has two parts. The umbra is the dark inner cone. The penumbra is the lighter part surrounding it.
"Umbra" is Latin for shadow. During totality, the moon is totally inside the umbra.
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 moves between the earth and the sun. 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.
The sky is blue because the 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 in the sky. From the moon, the earth is stationary, but goes through phases.
The temperature of the moon's surface 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. He said, "One small step for man, one giant leap for mankind." He should have said, "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 as proof. Of course, there is no wind on the moon. Actually, a horizontal bar 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. Bart was convinced that we 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.
The outer planets exhibit retrograde motion. They appear to travel backwards as the faster Earth overtakes and passes them. Mars is the dramatic 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 iron oxide. Rust! Its polar caps consist of frozen carbon dioxide. Dry ice! Mars has a huge volcano known as 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 for fossils. A journey will take 18 months, 9 months going and 9 months returning.
The Viking spacecraft landed on Mars in 1976. It found chemicals said to "mimic" life. The essentials for life are water, nutrients and energy. Scientists study the Atacama desert in Chile, the driest place on Earth, to learn more about Mars.
The Curiosity rover landed on Mars in August, 2012. It will try to determine whether microbes evolved. There may have been a zone of life in the early solar system extending from Venus to the asteroids.
The Martian moons are Phobos and Deimos. In Homer's Iliad, they were Fear and Panic, sons of the god of war.
The asteroid belt lies between Mars and Jupiter. Jupiter's influence kept this collection of rocks from coalescing into a planet.
Difference in size 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 have many.
Voyager 1 flew by Jupiter and Saturn. Voyager 2 went on to Uranus and Neptune. Voyager 2 spent 12 years (1977-89) on its 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 composed of hydrogen and helium, the most common elements.
Jupiter has bands because it rotates so fast that its clouds get stretched into patterns. The Great Red Spot is a storm. The Galileo probe reached Jupiter in 1995.
Jupiter has 67 moons. Europa, Ganymede, Callisto and Io 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 beautiful! They are made of rock and ice. As Saturn orbits the sun in 29 years, we see its rings open at the top, edge-on, open at the bottom and edge-on again.
The Cassini spacecraft imaged Saturn from above, showing it surrounded by rings. Giovanni Cassini discovered the gap in the rings.
Saturn has 62 moons, and Titan is the only moon in the solar system with an atmosphere.
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. William Herschel discovered Uranus in 1781.
Voyager 2 imaged Neptune's Great Dark Spot against blue methane. Johann Gottfried Galle, a German astronomer, discovered Neptune in 1846.
Small, rocky Pluto at the edge of the solar system is erratic. Its orbit takes it inside Neptune's. There are 5 moons: Charon, Nix, Hydra Styx and Kerberus. Clyde Tombaugh discovered Pluto in 1930. The New Horizons spacecraft reached Pluto in 2015, at a distance of 3 billion miles.
Beyond Pluto lies the Kuiper Belt (pronounced like viper). Kuiper Belt Objects (KBOs) are small, icy objects similar to Pluto.
The Voyagers left the solar system and are on their way to the stars. They contain recordings of Earth's languages and music.
The solar system and everything in it is 4.6 billion years old. This includes the sun, planets, moons, comets, meteors and 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 took place. Comets orbit the sun. They develop tails as 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 his comet but the first to predict its return.
I saw comet Comet Ikeya-Seki on Halloween morning, 1965. It was fuzzy and dim but worthwhile. 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 while protecting Earth.
I began watching the Perseids in the early 1960's. The Perseids occur in August. It is the best meteor shower. The night of August 11 and morning of August 12, 1964, I counted 351 meteors. 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! It was exploding and changing colors!
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. They are vaporized by friction a hundred miles up. In a shower, meteors emanate from a point called the radiant. A shower is named for the constellation behind its radiant. 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 the earth 50,000 years ago.
200 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.
Comets and asteroids make craters. The idea that the dinosaurs were killed by an asteroid is now accepted. Scientists point to Chicxulub (Cheek-shoe-lube) crater in Mexico's Yucatan peninsula as the impact that killed dinosaurs and two-thirds of all species. Evolution is driven by impacts.
Something hit Siberia in 1908, referred to as the Tunguska Event. Trees were flattened, but no crater was found. The comet or asteroid vaporized before impact.
Earth's atmosphere acts like sandpaper, smoothing craters out. Water erodes, and plate tectonics reshape the planet. Otherwise, the earth would look like the moon.
Stars are always there, even in the daytime when they are washed out by the sun. As the earth revolves in its orbit, different parts of the stellar panorama are exposed in the night sky. Constellations are identified with seasons.
Constellations are illusions. They are two dimensional. They existed in the minds of ancient Greeks. The stars are at various distances. They are three dimensional. Some appear bright because they are close. Some appear dim because they are far away.
The most recognizable constellations are Ursa Major (Big Dipper), Orion and 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, Capricorn, Aquarius and Pisces. The sun, moon and planets appear against the background of the Zodiac because of the flatness of the solar system. Everything is in the same plane.
The most elaborate story in the sky is that of Perseus and Andromeda, told by the fall constellations. There are Andromeda's parents, Cepheus and Cassiopeia, and the monster Cetus. Pegasus is the winged horse ridden by Perseus. Perseus holds the head of Medusa, represented by the variable star Algol.
Constellations are tied to Greek and Roman mythology. The stars forming the constellations are in our local star cloud and close to 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, and Vega. Arabs named the stars. We see 4000 at any one time. Stars twinkle because of our atmosphere. They are so far away that they appear as points of light even through large telescopes.
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 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, the pressure and temperature at the core will be great enough for nuclear reactions to begin.
Stars form in clusters. The Pleiades are condensing from surrounding gas. The Orion Nebula is likewise a stellar nursery. Nebulas glow when they reflect starlight. The Horsehead Nebula is dark, outlined by 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 two ways. Average stars like the sun become red giants. They die peacefully by exhausting their fuel. Antares and Betelgeuse are red giants.
When a star burns all its hydrogen, it burns helium to form carbon. Elements are made 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." This is a bad name because it has nothing to do with planets. The Ring Nebula in Lyra is a dying star.
A dying star shrinks to become a white dwarf, the core of a red giant.
Massive stars die by becoming supernovas and blowing up. A supernova was seen in 1987, in the Large Magellanic Cloud. Supernovas may become pulsars and black holes. Black holes are collapsed stars whose gravity is so great that light cannot escape.
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 stand outside the Milky Way, we would see a disk with a bulge at its center, shaped like a flying saucer or a fried egg. Our solar system revolves two-thirds of the way from the center toward the outer rim. It takes 200 million years to revolve around the galaxy, a period known as a cosmic year. The last time our solar system was in this place, dinosaurs roamed the earth. In the desert in 1979, there was a moment when I felt myself revolving around the galactic center.
Because we are inside the 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 in 1917, by Harlow Shapley. We see it when we know what we are looking at. The Milky Way circles the sky. Its bulging center lies in the direction of Sagittarius, where the star clouds are thick. The thin part of the circle, visible in winter, is in the direction of the rim. When we look at right angles to the Milky Way, we look out the top or bottom of the disk, where the stars are sparse. As we might expect, more galaxies can be seen through 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 the gas and dust, we use radio telescopes to study the center of our galaxy. The Milky Way is 12 billion years old.
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! This is what we call the Big Bang, the point at which space/time began.
Primordial 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 250 billion galaxies. Some are distinctive! The Whirlpool and Sombrero look like works of art. Galaxies are categorized according to their structures. 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 2.3 million light-years away and the furtherest object visible to the naked eye.
Charles Messier assigned numbers to fuzzy patches in the sky. He cataloged 110 objects 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 in turn make up superclusters. The Virgo supercluster is vast. The Local Group is in the Virgo supercluster. The universe is mostly empty.
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 one other. This is what is meant by the Expanding Universe. If we run it backwards, there is a point at which all the galaxies converge. Moreover, the further apart galaxies get, the faster they travel. The question becomes whether expansion will continue forever or whether there is enough gravity in the universe to pull it back together. This would be a Big Crunch and suggests an oscillating universe, one that alternately expands and collapses. Black holes may provide enough gravity for a Big Crunch. The universe is not expanding in space, but space is being created as it expands. The balloon analogy is used, blowing up a balloon with dots on it to represent galaxies.
We ask what was before the Big Bang. The answer is nothing. There was no space, no time and no events. It was the beginning in the truest sense.
E. P. Hubble was the greatest astronomer of the 20th century. Shapley thought external galaxies were inside our own.
Cosmology was the step I was trying to take since I was a teenager. Carl Sagan's Cosmos was a breakthrough. To paraphrase Sagan, "The Cosmos is everything that has been, everything that is and everything that will be." The terms "cosmos" and "universe" are interchangeable.
In Swim With Dolphins, I wrote, "I wanna see the stars, Mauna Kea's calling me." On September 13, 2003, I stood atop this 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 above 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 appeared lower and the constellation Scorpius higher than from Kentucky and Tennessee, 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 its redness." The moon rose! I enjoy astronomy and saw a bit of everything. 13 telescopes dot the summit of Mauna Kea. There are 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 our atmosphere's oxygen, but felt no different. It misted on the drive up, and rainbows were plentiful.
There are two kinds of telescopes: refractors and reflectors. The purpose of each is to gather light. The refractor uses an object lens. The reflector uses a mirror. The biggest telescopes are reflectors like those at Kitt Peak.
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 earthbound telescopes. I was initially mystified by the ST. It produced books of chaotic images with no theoretical breakthroughs.
Planetariums are places where sky shows and lectures are given. Star patterns are projected inside a dome. I have visited planetariums in Louisville, Nashville, Salt Lake City and New York.
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 and Gordon Cooper.
John Glenn got a hero's welcome after orbiting the earth three times in 1962.
Saturn 5 rockets sent men to the moon. Apollo 11 was the first landing. Neil Armstrong's footprint will last millions of years. Buzz 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 were:
Apollo 11 - Neil Armstrong, Buzz Aldrin
Apollo 12 - Charles Conrad, Alan Bean
Apollo 14 - Alan Shepard, Ed Mitchell
Apollo 15 - Dave Scott, James Irwin
Apollo 16 - John Young, Charles Duke
Apollo 17 - Harrison Schmitt, Eugene Cernan
The Apollo program has been followed by a golden age of planetary exploration as NASA worked with the Jet Propulsion Laboratory.
Competition between the United States and the Soviet Union drove the Apollo program. The spirit of cooperation which is supposed to put men on Mars is less of a motivator.
Space shuttles orbited 200 miles up while circling the globe in 90 minutes. The most famous to fly in the shuttles were women: Sally Ride and the ill-fated Christa McAuliffe. Challenger and Columbia exploded!
The shuttles were retired after 30 years. The Orion spacecraft will carry crews to the International Space Station. NASA wants to return to the moon, then go to Mars.
21 nations are involved in the ISS. Michael and I got a feeling for the it at the Kennedy Space Center at Cape Canaveral.
We will go to Mars during opposition. Mars is closest then at 35 million miles. It is more challenging than the moon, 150 times further.
Futurists have wild imaginations! They foresee mining the moon, terraforming Mars and colonizing the galaxy.
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. 1795 exoplanets have been confirmed.
Most exoplanets found so far are gas giants like Jupiter, unlikely candidates for harboring life. Scientists are searching for Earth-like planets.
The assumption that life began in the sea is questioned in the Space Age. It may be that Earth was seeded from space. The seeds of life may have traveled through interstellar space to take root in favorable conditions on Earth. This is the Panspermia theory.
Spores are among the hardiest forms of life. Spores may travel to planets via comets and meteors. They are less likely to travel through interstellar space, but we cannot rule it out. Our perceptions are evolving as we reach into space.
UFO sightings, close encounters and abduction stories are bogus. Such phenomena are explainable as aircraft and balloons, Venus and Jupiter, science fiction, psychiatric cases, hoaxes and lies. Roswell is a hoax! Claims that the government conceals UFO information are absurd.
Energy is the ability to do work.
The four forces in nature are the gravitational field, the electromagnetic field, and the strong and weak nuclear fields. The strong nuclear field binds protons and neutrons. Nuclear bombs unleash its energy. The weak nuclear field is associated with radioactive decay. Gravity is the weakest force, but long-range.
Einstein overturned Newtonian physics when he debunked the idea that objects attract. He showed that mass bends, curves and distorts space. The effect of this bending is what we call gravity. The analogy of a trampoline, bowling ball and marble is used. The bowling ball on the trampoline bends it. The marble moves toward the ball and will orbit it when the movement is right.
Einstein showed that space and time are connected. Gravity is the effect of mass curving space/time. The sun curves space/time. So does the earth.
Space is a fabric in which everything is embedded. Space has three dimensions: length, width and height. Objects move up & down, forward & backward, side to side and through time. Time is a 4'th dimension, being a direction in which things travel.
Our more exotic ideas seem like something from Star Wars. Dark matter is believed to account for 85% of the mass of the universe. We cannot see it, nor can it be detected. There is also the mysterious dark energy.
Wormholes are tunnels in black holes that lead to parallel universes. An infinite number of universes may make up the multiverse, each universe having its own Big Bang. Is this fantasy? Astronomy has gotten far out!
SCIENCE VS RELIGION
Science and religion have clashed 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. Should we believe that angels exist or should we regard them as part of ancient Jewish mythology?
Billy Graham believed in demons. I am 69 and have never seen a demon. 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 notion is ridiculous!
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 universe is 13.8 billion years old, will he linger another 13.8 billion years?
Can we believe Jesus ascended into heaven? Floated into space? In film biographies of Jesus, he has 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, analogy, simile or metaphor. What is God? Where is God? Theology must be man's creation! Books, art 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?
Jesus raised Lazarus from the dead only in our imaginations. We live in a natural universe! 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, I wonder.
Evangelist Jimmy Swaggart extolled the virtuous life while patronizing prostitutes. Morality seems more feasible to me within a scientific context. Scientists do not use nuclear energy to make bombs. It is military establishments with strong religious traditions that 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 redeems aliens.
The age of theology lay between 3000 B.C.E. 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 go with observation rather than revelation and evolution instead of creationism. Our eyes tell us how things are! It is what we suspected when we were 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 beyond man's imagination and his myth-making. Sagan left us with these words, "Extraordinary claims require extraordinary evidence!" Science is the candle; not mythology, not astrology, not religion.
We cannot 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 the Frenchman, Nicolas Lacaille, the last person to create constellations.
Animals dominate! There are two mammals, six birds, two reptiles, two fish and one 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 Columbia - dove
..9 Hydrus - serpent
10 Chamaeleon - chameleon
11 Dorado - swordfish
12 Volans - flying fish
13 Musca - fly
Lacaille added the scientific tools used by European mariners who sailed the south seas in the 17'th and 18'th centuries. These constellations are obscure and bear no resemblance to what they are supposed to be.
14 Horologium - clock
15 Pictor - painter's easel
16 Octans - octant
17 Circinus - compass
18 Antlia - air pump
19 Telescopium - telescope
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 make up Argo, the ship on which Jason and the Argonauts sailed.
26 Carina - keel
27 Vela - sail
28 Puppis - stern
29 Pyxis - compass
30 Indus - Indian,
31 Triangulum Australe - southern triangle
32 Crux - Southern Cross
The Cross' bright stars are known as the Three Marys. According to the gospels, the three Marys at the cross were the Virgin Mary, Mary Magdalene and Mary of Bethany, sister of Lazarus. This and the Beehive Cluster as a manger are the only allusions to Christianity in the sky.
The Southern Hemisphere has 6 first magnitude stars:
1 Canopus - Carina
2 Achernar - Eridanus
3 Alpha Centauri - Centaurus
4 Beta Centauri (Hadar) - Centaurus
5 Acrux - Crux
6 Bcrux - Crux
On Michael's 18th birthday, March 11, 2002, I took American Airlines to Los Angeles, then flew Qantas down 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 and 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 (ASNSW) met me at my motel. We drove through the Blue Mountains to Wiruna, three hours northwest of Sydney, and the South Pacific Star Party (SPSP)
I was lucky! The weather was great all three 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 and Achernar. I saw the Southern Cross and the Coalsack. I saw the hidden piece of the Milky Way and the Magellanic Clouds. The Clouds were fainter than I imagined. They are satellites of the Milky Way.
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 upside down.
The southern constellations are abstract! To trace even Centaurus and Argo would take time. Seeing Scorpius overhead stayed with me, that and seeing Orion and Scorpius in the sky at the same time.
I was impressed at how close Sirius and Canopus were and how the Southern Cross was not that far below Scorpius.
I will not forget walking out of the house that first night and looking up at the southern sky for the first time! It was ablaze with stars! The southern sky is spectacular because you also get the bright winter stars of the north.
ASNSW 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, part of the Commonwealth of Nations (British Commonwealth). The queen is the head of state.
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. I arrived back in Nashville, March 18, 2002. One week later!
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, large and detailed.
The Whirlpool is in Canes Venaciti. We know the small galaxy on the left lies behind the Whirlpool because 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.
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, blue and red. 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.
Michael and I attended the Grand Canyon Star Party at Yavapai Point, June 9-10, 2007. It was a good time for planets, and amateur astronomers had their telescopes out. We observed Venus, Jupiter and Saturn. Venus blazed as it hung over the Canyon. Even though I do not want Michael to get into astronomy because it takes you out of the world, an experience such as this is good.
Sky & Telescope
Tucson Amateur Astronomy Association
Las Vegas Astronomical Society
Grand Canyon Star Party
Central Nevada Star Party
Nebraska Star Party
Stargazer Online Richard Bell
Astronomical Society of New South Wales
South Pacific Star Party
Kitt Peak National Observatory
Louisville Astronomical Society
Welcome to the Universe
International Meteor Organization
American Meteor Society
..1 Apfel, Necia. Voyager to the Planets. New York, Clarion Books, 1991
..2 Astronomy Magazine. 50 Greatest Mysteries of the Universe. Waukesha, Kalmbach, 2007
..3 Baker, Robert H. Introducing the Constellations. New York, Viking Press, 1957
..4 ________. When the Stars Come Out. New York, Viking Press, 1946
..5 Bernhard, Bennet & Rice. Handbook of the Heavens. New York, New American Library, 1959
..6 Branley, Franklin M. The Milky Way: Galaxy Number One. New York, Crowell, 1969
..7 Couper, Heather and Nigel Henbest. Space Scientist Series. New York, Franklin Watts, 1980s
..8 Fanning, A. E. Planets, Stars and Galaxies. New York, Dover, 1966
..9 Ferris, Timothy. Coming of Age in the Milky Way. New York, William Morrow, 1988
10 ________. The Red Limit: the Search for the Edge of the Universe. New York, William Morrow, 1977
11 ________. The Whole Shebang: A-State-of-the-Universe(s) Report. New York, Simon & Schuster, 1997
12 Fisher, Clyde. Exploring the Heavens. New York, Thomas Y. Crowell, 1937
13 Gutsch, William A. 1001 Things Everyone Should Know About the Universe. New York, Doubleday, 1998
14 Hathaway, Nancy. The Friendly Guide to the Universe. New York, Viking, 1994
15 Kerrod, Robin. The Book of Constellations: Discover the Secrets in the Stars. Barron's, 2002
16 ________. The Moon. Minneapolis, Lerner Publications, 2000
17 Knight, David C. Galaxies: Islands in Space. New York, William Morrow, 1979
18 Muirden, James. The Amateur Astronomer's Handbook. Third Edition. New York, Harper & Row, 1983
19 Norton, O. Richard. Rocks from Space: Meteorites and Meteorite Hunters. Missoula, Montana, Mountain Press, 1994
20 Phillips, Cynthia and Shana Priwer. Essential Astronomy: Everything You Need to Understand the Mysteries of Our Universe. Avon, Adams, 2007
21 Ride, Sally and Tam O'Shaughnessy. Exploring Our Solar System. New York, Crown, 2003
22 ________. The Mystery of Mars. New York, Crown, 1999
23 ________. The Third Planet: Exploring the Earth from Space. New York, Crown, 1994
24 Sagan, Carl. Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium. New York, Random House, 1997
25 ________. Cosmos. New York, Random House, 1980
26 ________. Pale Blue Dot: A Vision of the Human Future in Space. New York, Random House, 1994
27 ________. The Demon-Haunted World. New York, Random House, 1995
28 Steel, Duncan. Target Earth: The Search for Rogue Asteroids and Doomsday Comets. Pleasantville, Reader's Digest, 2000
29 Wilford, John Noble. Mars Beckons: the Mysteries, the Challenges, the Expectations of Our Next Great Adventure in Space. New York, Alfred A. Knopf, 1990
30 Zim, Herbert S. and Robert H. Baker. Stars: A Guide to the Constellations, Sun, Moon, Planets and Other Features of the Heavens. New York, Golden Press, 1975
Originally written 1995-1996