Comet Lulin, C/2007 N3 on Feb 6, 2009

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Expand view Topic review: Comet Lulin, C/2007 N3 on Feb 6, 2009

Re: Comet Lulin, C/2007 N3 on Feb 6, 2009

by neufer » Sat Feb 07, 2009 3:29 pm

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OENONE to PARIS [Ovid: Heroides V.]
.........................................
Hoc tua (nam recolo) quondam germana canebat
. sic mihi diffusis vaticinata COMIS:
"quid facis, OENONE?
quid arenae semina mandas?
non profecturis litora bubus aras !"
.........................................
Once, I recall, your sister sang this to me,
. With STREAMING HAIR, speaking prophecy:
. "What are you doing, OENONE ?
. Why do you trust your seeds to sand?
. You plow the shore with OXEN that are of no use."
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http://antwrp.gsfc.nasa.gov/apod/ap040514.html
.
<<Explanation: Moderately bright Zubenelgenubi (Alpha Librae) is the star just off the upper right hand limb of an eclipsed Moon in this telescopic view from Port Elizabeth, South Africa. Actually the second brightest star in the constellation Libra, Zubenelgenubi is fun to pronounce (try zoo-BEN-al-je-NEW-bee ...) and rewarding to spot in the night sky as it has a fainter companion star, seen here on the far right. Astronomer Francois du Toit reports that both stars were visible to the unaided eye on the night of May 4th, during the Moon's total eclipse phase. Orbiting a common center of gravity once every 200,000 years or so, the two stars are both larger and hotter than the Sun. About 77 light years away they are separated from each other by over 730 light hours -- about 140 times Pluto's average distance from the Sun. Zubenelgenubi was once considered the southern claw of the nearby arachnologically correct constellation Scorpius. What star was the northern claw? Zubeneschamali, of course.>>
.............................................
<<ZUBENELGENUBI (Alpha Librae). Dim Libra, which 2000 years ago held the autumnal equinox in its balance pans, is identified chiefly by two stars to the northwest of Scorpius that have delightful names, Zubeneschamali and Zubenelgenubi. They harken back to the ancient times when they were considered the outstretched claws of the Scorpion, making the two something of a double constellation. "Zubenelgenubi" derives from an Arabic phrase meaning the "Scorpion's southern claw," while the name of its mate (to which it is not physically related) refers to the northern claw. Bright third magnitude (2.75) and somewhat dimmer than Zubeneschamali, Zubenelgenubi still received the Alpha designation. Rather like Mizar and Alcor, it is a naked eye double, flanked four minutes of arc (0.06 degree) to the northwest by a fifth magnitude (5.15) companion. The two are probably a physical pair, as they move through space together, both of them 77 light years away from us. The fainter (called Alpha-1 because it is the westerly of the two) is a class F (F4) star that at about 6700 Kelvin is 1000 Kelvin hotter than the Sun, while the brighter (Alpha-2) is a much warmer white class A (A3) subgiant with a temperature of 8500 Kelvin. The two are separated by at least 5500 Astronomical Units, nearly 140 times Pluto's distance from the Sun, and maybe more since we do not know the exact difference in distance. At that separation, the orbital period would be over 200,000 years. From Alpha-2, Alpha-1 would appear as a brilliant star of the minus tenth magnitude, 100 times brighter than Venus does in our sky. From Alpha-1, Alpha-2 would be 10 times brighter yet and rival our full Moon. Alpha-2, the brighter, is deceptive however. It is itself a double made of two class A stars, one 45 percent brighter than the other. From Earth they are a mere hundredth of a second arc, only a few tenths of an astronomical unit, apart, comparable to Mercury's distance from the Sun. Even from Alpha-1 they would be inseparable with a human eye. There is some evidence that this triple star system belongs to a hugely extended group of stars (the "Castor Moving Group") that move together through space and that include Castor, Vega, and Fomalhaut. Zubenelgenubi proper (Alpha- 2) has an enhancement of metals in its atmosphere most likely caused by separation of elements, some rising up, others drifting down, the culprit probably the brighter of the very close pair that makes it up.>>
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. http://hsa.brown.edu/~maicar/Paris.html
.
<<While he was tending his cattle on Mount Ida, PARIS fell in
love with the Nymph OENONE, daughter of the river god Cebren
who was taught the art of prophecy by Apollo. PARIS took OENONE
to Mount Ida, where he had his home, & PROMISED her that he would
never desert her. But OENONE, said that one day he would fall
in love with an European woman, whom he would bring back with him,
and with her all the horrors of war. And to this disappointing
picture she added that he was to be wounded in that war, and that
nobody would be able to cure his wound, except herself, who was
well acquainted with the Phrygian forests and its healing herbs.
.
This Nymph, who loved PARIS when he still was a poor SHEPHERD
(for at the time it was not known that he was a Trojan prince)
never accepted, though she foretold it, that this young
man, who had gone around writing OENONE with his blade
in the trunks of the trees, could endure to desert her.>>
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Comet Lulin, C/2007 N3 on Feb 6, 2009

by mikebrous » Sat Feb 07, 2009 6:34 am

Comet Lulin, 215 Oenone and Alpha Librae on Feb 6th, 2009, 11:20 UT. TV-85 at F/5.6, 15x240 sec @ ISO 1600, Hutech Canon 350 XS, IDAS-LPS, Atlas EQ-G w/EQMOD.

Click on the image to see a higher resolution version.

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