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Our installment next month (September) will focus on the constellations of Cassiopeia, Perseus, Pegasus and Andromeda Thank you. Bob McGovern. August Skies – Cepheus, Capricornus tiny Delphinus and Sagitta and the Perseid Meteor Shower. For the Naked Eye - (for some fascinating mythologies and astronomy facts simply Google the names found in the text below and check out the sky maps by Sky & Telescope online at: http://www.skyandtelescope.com/observing/skychart/ ). The Constellation Cepheus the King – Cepheus (sē-fē-əs) is the name of a mythological king of Ethiopia, the son of Belus, king of Egypt and the grandson of Poseidon. This is not the modern country of Ethiopia south of Egypt in Africa but was then referred to as a kingdom on the eastern shores of the Mediterranean (Phoenicia) based in the city of Joppa, now called Jaffa and part of Tel Aviv, Israel. Cepheus was married to Cassiopeia, was the father of Andromeda and the father-in-law of Perseus, all interconnected constellations that will be described in next month’s soap opera section of this newsletter. This is an ancient constellation representing a king and dates back to at least 400 BC in Greece. To me, the shape of the brightest stars in this constellation resembles a lopsided house or, if someone insisted that it represent a primate type figure, I’d make it a gnome with a big pointy hat and name him Gulcifer. Given the choices, how would you describe this stellar grouping? proposed “Gulcifer” the “crooked house” Cepheus as accepted The most well known star in Cepheus is the variable star Delta Cephei (marked by the arrow pointing at the gnome’s right toe above) first described by John Goodridke, an 18 year old deaf student in England in 1784. This class of variable stars, now known as Cepheids, have allowed astronomers to estimate intergalactic distances since their pulsating periods are related to their absolute magnitudes. Delta Cephei is a pulsating supergiant star with a period of 5.4 days. Although there are no Messier objects in Cepheus, the area is quite rich with stars as part of it lies in the Milky Way just above Cygnus. The Constellation Capricornus the Sea Goat – The plane of our solar system projected against the stars contains 12 constellations, the ecliptic or the zodiac if you’re into astrology. Three of these constellations are considered the water signs and this area of the heavens was described as the sea: Aquarius the water carrier, Capricornus the sea goat and Pices the fish. These constellations never get very high in the sky for us here in Rochester and due to the approximate 23 degree tilt of our Earth’s axis, it appears that our sun, on the first day of winter, can be seen directly overhead at locations of about 23 degrees south latitude – a circle around the earth known as the Tropic of Capricorn. It is thought that the “goat” part of Capricornus pertains to the observation that the sun started to “climb” back towards the north after reaching this constellation, much like a goat is known for climbing, and the “fish tail” part pertains to it leaving the “wet” months of winter. Capricornus is best viewed from a dark location as the stars are quite faint but once you’ve found it, you can easily recognize it as a part goat facing to the right with the back end having the tail of a fish. The shape reminds me of the smile of the Cheshire Cat. Capricornus is one of the most ancient of constellations and was recorded in the Babylonian star charts as the “Goat Fish” about 3,000 years ago. There is a great deal of mythology around Capricornus and one describes the origin from the god Pan. The worship of Pan spread throughout Greece from Arcadia around the time of the battle of Marathon. He was the god of the forest, pastures, shepherds, mountains and every place natural. He protected flocks and had a great time dancing around and playing his flute. Pan was also noted for his sexual powers and, through trickery, seduced Selene, goddess of the moon. One myth tells of Pan being attacked by a monster and being forced to dive into the Nile to escape. The half of Pan that stayed above the water retained the features of a goat and those under the water turned into a fish. There is lots of fun reading about Pan! Neptune was discovered in Capricornus by Johann Galle in 1846 although it was observed by Galileo in 1613 and his records showed that he even noticed that it had moved somewhat in later observations. Neptune was around magnitude 8 and did not show a disc in his equipment. Johann Galle, however, made his observations of selected areas based on mathematical calculations of his own and by others using Newton’s laws of gravitation and how they affected the motion of Uranus. Since its discovery in 1864, Neptune is once again in the constellation of Capricornus on its 163 year trip around the sun. It is currently shining at magnitude 8 at a distance of 29 astronomical units from the sun and is about 3 degrees east of brilliant Jupiter at mid month. The Constellation of Delphinus the Dolphin This is just a tiny constellation but an ancient one just the same. You can locate this pretty star pattern by looking for the little quadrilateral just to the east of a line drawn between the bright stars Deneb and Altair in the “summer triangle”. The 4 brighter stars in the head also form the asterism commonly called Job’s Coffin (marked in blue) for reasons lost in history. A few fainter stars form the body and tail of the dolphin. Delphinus was a messenger of Poseidon, god of the sea. Poseidon sent the dolphin with messages to one of the sea nymphs to become his wife who found it impossible to disappoint this cute animal. For accomplishing this, Poseidon gave the dolphin immortality in the heavens. The Constellation of Sagitta the Arrow Extend this line to Deneb extend this line to Vega The blue stars and connecting lines define the two tiny constellations of Delphinus and Sagitta. Sagitta lies within the boundaries of the “summer triangle” asterism and is imbedded in the Milky Way so sweeping through this area with your binoculars of wide field telescope is well worth the effort. In dark skies, Sagitta is formed by 4 stars and was told by the ancient Greeks to be the arrow that Hercules used to kill Aquila the eagle. If you look at any star chart, however, the arrow is above the eagle and heading in the wrong direction! It was a clear miss of the eagle but appears headed towards the belly of Vulpecula the fox (a very faint constellation within the “summer triangle”). There are other stories that associate Sagitta as the arrow of Cupid. The Perseid Meteor Shower – I have great memories from my childhood of lying in a field across the road from the home where I grew up in (very) rural Pennsylvania (Bear Hollow) watching the Perseid meteor showers every August. Just lying there wrapped up in a blanket and listening to the crickets in pitch blackness until I fell asleep was something that would paralyze me now but was certainly magical then. The source of the Perseid meteor shower is actually debris from the comet SwiftTuttle. Every year, the earth passes through the debris stream left by the comet and the earth's atmosphere incinerates the particles into the glowing embers called meteors or “falling stars”. The shower peaks early afternoon on the 12th, so the morning of the 12th (midnight to dawn) is the best time to watch although quite a few should be visible a few nights before and after this date. The meteors from this shower appear to radiate from the constellation Perseus which is located low in the NE sky. It’s important then to find a dark location with a good view to the NE and enjoy the show. The bright moon present this year will obscure the fainter ones but you should still see quite a few. Like most celestial events, they are best viewed from a dark, moonless location. Maybe next year the moon will cooperate. The More Prominent Planets – Jupiter - Jupiter is absolutely brilliant at magnitude minus 3 low in the SE in the constellation of Capricornus at around 10 pm. It reaches it highest point above the horizon around 3 am at mid month and still, as of August 10, shows a faint scar from the asteroid or comet impact that occurred last month. The Moon and the Moon and Venus- This month the full moon is on August 6th and is called the “Full Sturgeon Moon” by some Native American tribes around the Great Lakes as it was the prime time to fish for sturgeon. It was also called the “Green Corn Moon” or the “Grain Moon”. A few tribes called it the “Full Red Moon” because of its color when rising through the warm summer haze. The waning crescent moon will make a beautiful early morning pair with the “morning star” Venus on the 17th and 18th of the month with Venus at a brilliant magnitude of minus 4.