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- 1. constellation is a group or clusters of starsthat make an imaginary shape in the nightsky.constellations are formed of bright starswhich appear close to each other on thesky, but are really apart in space;constellations are arbitrary groupings ofstars that have been constructed so as toassist in the location and identification ofstars.
2. refers to a pattern that is formed whenimaginary lines are drawn in betweenstars close in proximity, forming animage.are patterns that appear identical toobjects 3. are based on grid segments onthe celestial sphere and are notbased on patterns. 4. An Asterism- is a morerecognizable part of the largerconstellation.Example: The Big Dipper is a partof Ursa Major, the Big Bear, andthe Little Dipper is a part of UrsaMinor, the Little Bear. 5. Astronomers: Constellations are not real.They are totally imaginary things thatfarmers and astronomers have made upover the past 6,000 years (and probablyeven more.) 6. Claudius Ptolemy-defined 48 lists ofconstellations in the2nd century in hisbook entitledALMAGEST. 7. Johann Bayer- in hisUranometria(1603) added 12constellations fromexpedition to S-Hemisphere. 8. Jakob Bartch(1624)-added 3constellations. 9. Johannes Hevelius-added 9 southernconstellations in hisFirmamentumSobiescianum siveUranographia. 10. Nicholas Louis deLacaille- added 14constellations in1763. 11. JohnFlamsteed(1929)and Johan ElertBode(1801)-produced otherelegant star atlases. 12. Mid-1800s Ptolemys largestconstellation ArgoNavis, has beendivided intocarina, puppis,and vela 13. In 1922 theInternationalAstronomical Unionrecognized 88constellationsbased on the 48listed by Ptolemy inhis Almagest in the2nd century andother astronomers. 14. are those that, from the viewers latitude, never set.circumpolar stars or constellations daily tracescircles around the north celestial pole without settingor dipping below the horizon. They move in acounterclockwise direction.are those that are close enough to the NorthCelestial Pole that they remain above the horizon allthe time as the sky turns.are always above the horizon, even in the daytimeand visible at all seasons.Examples:1. Camelopardalis, 2. Cassiopeia, 3. Cepheus, 4.Draco, 5. Ursa Major and 6. Ursa Minor. 15. are the remaining non-circumpolarconstellations that are visible at theobservers latitude.These constellations will rise and set as theearth turns.They appear in the sky during reasonableevening hours only at certain times of theyear.Examples: are the zodiac(Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquariusand Pisces). 16. Summer ConstellationsConstellations around the Summer Triangle1. Cygnus (with the bright star Deneb)2. Lyra (with Vega)3. Aquila (with Altair)Constellations in the Southern Sky1. Scorpius (with Antares)2. Sagittarius (teapot) 17. Fall Constellations1. Pegasus2. Andromeda( with M31, a galaxysimilar to our Milky Way)3. Perseus (partly circumpolar) 18. Winter ConstellationsAlong the Ecliptic1. Taurus2. GeminiEquatorial1. Orion (with Betelgeuse, Rigel and theGreat Nebula)2. Canis Major (with Sirius)3. Canis Minor (with Procyon)The rest of the family1. Auriga (with Capella) 19. Spring Constellations1. Bootes2. Leo3. Corona Borealis4. Hercules