History of Astronomy

Let us begin at the beginning of universal time, with what scientists believe was a massive explosion called the Big Bang. It is from this explosion that our sun was eventually formed, and from this same explosion the eight planets of our solar system were flung out into space with our orbiting moons, all circling our newly born sun. Then we will se how different periods of human development have had intense scientific discoveries, while others show little scientific discovery. In fact, you will see how the recent 1800s, and 1900s, has been an amazingly rich period of astronomical studies and discoveries. You will notice some famous names, others you will not have heard of, and towards more recent years, the names of women also becoming involved in astronomy.

Assignments

Your assignment - required of every Camp Internet student - is to pick one of the discoveries from 20,000 years ago to the present, research what it is, and send us a definition by e-mail to camp@campinternet.net. 2-6 sentences is fine. We will then create a Student Astronomy Dictionary for you all to read and learn from.

You also can take the Astronomy Quiz once you have gone over the time line - see what you can learn about the history of the earth, the solar system and the universe. Some of the findings are about stars millions of light years away, some are about objects so tiny even the most powerful microscopes must be adapted to see them - and all are elements in understanding the universe.

Time Line

0 - The Big Bang "The origin of time, space and energy - the universe as we know it".
4.5 billion years before Present (BP) - our sun and planets congeal from a cloud of gas, dust, and stellar debris in a part of the spiral arm of the Milky way galaxy.
3.8 billion years BP - Earth has cooled down enough for a crust to form and the first rocks on earth are dated from this time.
3.5-3.2 billion years BP - Microscopic living cells evolve on earth - the first life forms.
1.8-1.3 billion years BP - Plants begin to appear and oxygen first is created, building an atmosphere for life.
700 million years ago - The first animals - flatworms and jellyfish - appear
435 million years ago - Life migrates from the seas to the land
395 million years ago - Age of the Insects begins
325 million years ago - Age of the Dinosaurs begins
200 million years ago - Age of the Mammals begins
180 million years ago - Single continent of Pangea begins to separate and individual continents begin to form.
65 million years ago - Major meteor collides with the earth changing life completely due to a cloud of dust that blocks out he sunlight and impacts on plants and animals of all kinds.
20 million years ago - Earths atmosphere becomes similar to what we know today
1.8 million years ago - first human-like life appears, Homo Erectus
600,000 years ago - first Homo Sapiens appear
150,000 years ago - Wooly Mammoths roam the earth
40,000 years ago - Human languages form
20,000 years ago - Agriculture is invented and human migrations begin to all continents
6,700 years ago - First calendar created in Babylon
5,500 years ago - Writing is invented
4,500 years ago - Stonehenge observatory is built
4,200 years ago - Astronomy is practiced as a science in Egypt, Babylon, China and India
3,500 years ago - Sundial invented in Egypt
2,650 years ago - Mayan temples and observatories are built
2,500-2,100 years ago - Greek philosophers and scientists predict that invisible atoms exist as the basis of matter, that geometry is the basis of our experienced reality (Pythagorous, Plato, Euclid), one that the earth orbits the sun (Aristarchus), and another that the earth is the center of the universe (Ptolemy)
2,060 years ago - A major work on cosmology is written - On the Nature of things, by Lucretius, a Roman
2,000 years ago - Birth of Christ estimated and our calendar with After Death dates is counted from here.
400-450 AD - Rome is destroyed by roaming barbarians, scientific thought and cultural expression goes into a Dark Age
963 AD - A middle easterner, Al Sufi, write Book of the Fixed Stars and mentions nebulae
1001 - Leif Erickson sails from Northern Europe to the New England coast of the Americas
1276-1292 - Marco Polo visits China, linking European and Asian culture, science, and discovery
1400 - Renaissance of learning and inquiry takes place in Europe
1492 - Columbus bumps into the Americas in search of a shorter route to the Orient
1522 - Magellan's sailors circumnavigate the globe using the stars as their points of reference.
1543 - Copernicus writes On the Revolutions as a study of our solar system and universe.
1572 - Tycho sees a nova (a new star) and this refutes Aristotle's thoughts from ancient Greece that the universe is a fixed, unchanging skyscape.
1604 - Galileo and Kepler observe a supernova, and Galileo develops laws of motion.
1609 - Galileo observes the nigh sky through a telescope; Kepler observes that the planets orbits are elliptical around the sun
1616 - Roman Catholic Church bans all books that say the earth moves - making heretics of the scientists of the day, and threatening their lives if they refuse to deny their claims.
1665-66 - Issac Newton, home from college, recognizes gravitational laws.
1686 - Bernard de Fontelle writes a work - Entreaty on the Plurality of Worlds - that popularizes that the universe contains many worlds
1687 - Issac Newton published Principia - a document of his beliefs about the Universe and the physics that govern its existence and behavior
1716-18 - Halley observes that the planets have changed position since Greek measurements were made before Christ, and discovers a means to measure by triangulation the distances between planets, and to predict their motion.
1750-1784 - French amateur astronomer Messier catalogs celestial objects that later prove to be star clusters, interstellar gas clouds, and other external galaxies.
1800s - Scientists discover infrared light (Herschel 1800), ultraviolet light (Ritter 1801), fossil record of first known extinct species (Cuvier 1801),electromagnetic forces (Orsted 1820), first precise measurement of the distance to a star, wavelengths of sound of moving objects (Doppler 1842), first astronomical photograph (Bond 1850), velocity of light refined (Foucault 1862, Michelson 1879), photographs of the Milky Way lead to understanding that there are dark clouds of interstellar matter (Barnard 1895), the electron is discovered (Thomson 1897), radioactive elements are isolated in radium and polonium (Marie and Pierre Curie 1898).
1900s - Scientists continue discoveries - quantum theory of radiation leading to quantum physics (Planck 1900), discovery of using radioactivity to measure ancient minerals (Rutherford 1904), theory of relativity of measurements of time and space (Einstein 1905), rotation of our galaxy in a regular direction (Kapteyn 1905), theory of atomic structure where atoms are seen to orbit he nucleus much like our planets orbit the sun (Bohr 1913), luminosity and color of stars plotted (Hertsprung-Russell 1913), spectral analysis perfected to measure luminosity of stars and predict the distances to millions of stars (Adams-Kohlschutter 1914), stars classified by spectral types (Annie Cannon 1915), theory of relativity published noting effect of gravitation on curved space "delivering cosmology from the ancient dilemma of a finite versus an infinite universe" (Einstein 1916), stars understood as gaseous spheres (Eddington 1916), worlds largest telescope - 100" - begins operation ( Mt. Wilson, USA 1918), Andromeda spiral found to be its own galaxy (Opik 1922), explaining universe cosmology found consistent with theory of relativity ((Friedmann 1922), suns lements found to be similar to those of the earth's crust (Cecilia Payne 1923), quantum mechanics formed (Born, Jordan, Heisenberg 1925), Milky Way thought to be rotating (1926), expanding universe cosmology published (Lemaitre 1927), nuclear fusion thought to provide the energy that powers stars (Gamow 1928), universe is measured as being expanding (Hubble 1929), Discoveries of positrons, neutrinos, neutrons, mesons, nuclear fission (1931-1939), Milky way found to emit radio waves, opening of door to the science of radio astronomy (Jansky 1932), first radio map of the Milky way made with a backyard telescope (Reber 1940), age of Andromeda charted by color of its tars - redder in center are older, blue on outer edges are younger (Baade 1944), radio sources in other galaxies found (1946), 200" telescope at Mt. Palomar dedicated (1948), radiocarbon dating developed (Libby 1948-50), quasars, the most distant class of objects in the universe, are discovered (Sandage - Matthews 1960), pulsars, extremely dense neutron stars, are identified (Jocelyn Bell - Hewish 1967),
1968 - Man walks on the Moon