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Constellations. Star Lore and Patterns. 88 Modern Constellations. Some are ancient & some are modern Most recently updated in 1922 Most stick figures are technically “asterisms” Asterism - star patterns that is not a constellation (Big dipper within Ursa Major) . The Celestial Sphere.
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Constellations Star Lore and Patterns
88 Modern Constellations Some are ancient & some are modern Most recently updated in 1922 Most stick figures are technically “asterisms” Asterism - star patterns that is not a constellation (Big dipper within Ursa Major)
The Celestial Sphere Imagine all things in the sky are on a celestial sphere at some fixed distance from Earth This helps us locate things in the sky Constellations mark the boundary of a specific area on the sphere
Constellations Change Over Time As stars move, constellation shapes change Stars are not necessarily close to one another The Ursa Major Moving Group is an exception Why?
Stars that appear close in the sky may not actually be close in space
From many sources... We have constellations from ancient and medieval sources: Greek, Phoenician, Chinese, Persian, & Arabic Uses? Our current list of 88 dates to 1922. The boundaries are supposed to be rigid. The Almagest was first major attempt at a star chart by humans. It was also the largest set of books about astronomy in the ancient world. Written by Ptolemy. Lost to European astronomers and rediscovered during the renaissance.
Northern & Southern There are some constellations that are only seen in one hemisphere. An observer’s latitude on Earth determines which can be seen on a particular date. Many southern constellations vary from the mythological theme.
Labeling The Stars The stars in constellations are labeled generally according to brightness. This isn't always true, but that is the general idea. The system we currently use is called the Bayer Designation. We assign Greek letters to the most prominent stars in a constellation plus the genitive for that constellation.
Magnitude - a measure of brightness • When we study constellations, one way to describe something is by how bright is appears. • We measure "apparent brightness" using a scale called magnitude. • The lower the magnitude number, the brighter the object.
Magnitude - a measure of brightness • Vega is set at magnitude 0 • Few stars are brighter: Sirius is brightest at -1.5 • The Sun is a whopping -27 • Full Moon is -13 • Humans can't really see anything higher than mag 6 • Telescopes help for dimmer than 6.
Constellation Project A pair of students will present a short description of a constellation Describe the history and mythology of the constellation Describe or create an alternative mythology and pattern Points for clarity, depth of knowledge, shared work ethic, and creativity
Antlia Nicolas Louis de Lacaille introduced it in the 18th century The constellation represents the air pump invented by English scientist Robert Boyle. Too faint for the Greeks to acknowledge Mostly visible in southern hemisphere
Antlia: Neighbors Antlia is near these constellations: Hydra the water snake Pyxis the compass Vela the sails of the Argo And Centaurus the centaur
Notable Stars in Antlia Alpha Antliae - The brightest star shining at magnitude 4.2. It is located some 360 light years away from Earth. Eta Antliae - Double star at magnitude 5.2, located 110 light years away from Earth. Zeta Antliae - A wide double star, easily split with binoculars into its two components of 6th-magnitude..
Notable Deep Sky Objects in Antlia NGC 2997 - An 11th-magnitude spiral galaxy discovered in 1793 by William Herschel. NGC 3132 (The Southern Ring Nebula) - A bright and large planetary nebula located very close to the border with Vela.
Constellation Edoras This constellation represents the capital of the mythical Rohan from the JRR Tolkien’s Middle-Earth universe. The Rohirrim are similar tomedieval Norsemen. This mythology is similar to the “mead hall” Heorot in the tale of the hero Beowulf. The “mead hall” is common in Norse history and mythology.
References Antlia star imagehttp://commons.wikimedia.org/wiki/Image:Antlia_bode.JPG History of Antilahttp://en.wikipedia.org/wiki/Antlia Antlia atlas depictionhttp://www.ianridpath.com/startales/antlia.htm Antlia statisticshttp://www.nightskyinfo.com/constellations/antlia/ Edoras informationhttp://www.glyphweb.com/arda/ Beowulf informationhttp://en.wikipedia.org/wiki/Beowulf