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In the January Sky...
· After sunset, look above the western horizon. There, brilliant Jupiter graces the evening sky.
· The winter night sky is filled with brilliant stars.
· An ancient constellation, Auriga was pictured as a goat herder by the Greeks and Romans.
· Auriga is a beautiful circlet of jeweled stars, gracing the sky overhead.
· Capella, the sixth-brightest star in the sky, is a double star. The two stars are yellow stars like our own Sun, but they are about 10 times larger andare 50 and 80 times brighter.
· Near Auriga is the large constellation Taurus the Bull.
· In Greek legend, this group of stars represented Zeus in the disguise of awhite bull with golden horns.
· His eye is the orange, conspicuous Aldebaran, a red-giant star in theadvanced stages of its evolution.
· The Bull's V-shaped head is created by the Hyades, a beautiful cluster of stars, easily seen with the naked eye.
· The Pleiades star cluster lies near the head of the Bull. Also known as "the Seven Sisters," this large and bright star cluster is the best known in the sky.
· The unaided eye can see only six or seven stars, but the Pleiades cluster contains over 250.
· Binoculars showcase the cluster at its best.
· The stars in this stellar swarm are hot and young, recently born in a tumult of cosmic dust and gas. A dusty cloud through which they are passing reflects their blue light.
· Magnificent Saturn rises after midnight. Look for it above the easternhorizon to the right of the bright star Arcturus.
· By dawn, dazzling Venus has also risen in the east.
Other Astronomy Facts...
· If you watch the sun set on a clear, flat horizon (from the top of a tall building, or from a boat at sea, for instance), you may see a momentary "green flash" as the earth's atmosphere bends and disperses the sunlight, prism-fashion.
· If you made a model of the earth, 40 cm in diameter, the atmosphere would be less than a mm thick.
· As a result of human activity in space, there are over 10,000 large pieces of debris up there, and millions of smaller pieces. You have to watch where you are going!
· The moon is as black as coal; it reflects only 6 per cent of the light which falls upon it.
· The full moon looks larger when it is near the horizon -- but it's just an optical illusion.
· You can remember the order of the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto by remembering "my very educated mother just showed us nine planets".
· Saturn's rings -- which are made of chunks of rock and ice, orbiting above the equator of the planet -- are 300,000 times wider than they are thick. Relatively thinner than a sheet of paper! By the way: the average density of Saturn is less than that of water, so Saturn would float in a very large bathtub (but would leave a ring behind).
· Uranus was the first planet to be "discovered" (by William Herschel in 1781). It's pronounced UR'-a-nus, not the other way. Several of its moons have been discovered by Canadian astronomers.
· People argue about whether Pluto is a planet. It's smaller than earth's moon, and it's just the largest of thousands of icy worlds in the outer solar system. But for historical reasons, astronomers consider it a planet.
· Comets are balls of ice. When they are near the sun, the ice evaporates to form a cloud of gas. The sun's radiation pushes the gas into a "tail", which always points away from the sun. So when a comet is moving away from the sun, it's chasing its tail!
· Our sun isn't an average star; it's more massive and powerful than 95 percent of its neighbors.
· In five billion years, the sun will swell up to become a red giant, and will engulf the inner solar system. But there are many things that earthlings must worry about before that.
· Betelgeuse, the reddish star in the upper left shoulder of the constellation Orion, is already so large that, if you put it where the sun is, its atmosphere would stretch beyond the orbit of Mars.
· A supernova is a stellar explosion which occurs when a dying star collapses, releasing enough gravitational energy to blow the star apart. The brightest supernova in 400 years was discovered, in 1987, by Canadian astronomer Ian Shelton.
· All the atoms in your body, with the exception of hydrogen and helium (there isn't much of that) were created in stars, and blasted into space by stellar explosions such as supernovas.
· A black hole is an object whose gravity is so strong that nothing -- not even light -- can escape. Very massive stars collapse, at the end of their lives, to become black holes. The first example was co-discovered by Canadian astronomer Tom Bolton.
· There are enough ethyl alcohol molecules in interstellar space to make a trillion bottles of whisky.
· If there were aliens in our galaxy, as intelligent and technological as we are, we could communicate with them, using present-day radio technology.
· Astronomer Edwin Hubble (the Hubble Space Telescope is named after him), went to Oxford University on a Rhodes Scholarship. For that, you have to be athletic as well as bright; he was a very good boxer. As an astronomer in Los Angeles, he mixed with movie stars; he was a handsome fellow!
· In the universe, you can look back in time. Since light travels at the fast but finite speed of 300,000 km/s, we see the sun as it was 8 minutes ago, the nearest other star as it was 4 years ago, the nearest large galaxy as it was 2 million years ago, and the most distant galaxy as it was 10 billion years ago.
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