La Memoria - 10 'Spica'

Spica looks like one star, but it is at least two stars, both larger and hotter than our sun, orbiting only 18 million kilometers (11 million miles) apart. That’s in contrast to 150 million kilometers for Earth’s distance from our sun. Their mutual gravity distorts each star into an egg shape, with the pointed ends facing each other as they whirl around, completing a single orbit in only four days. Follow the links below to learn more about Spica, brightest star in the constellation Virgo the Maiden.


Located close to the ecliptic, Spica can be occulted by the moon sometimes by the planets. The last planetary occultation of Spica occurred when venus passed in front of the star (as seen from earth) on November 10, 1783. The next occultation will occur on September 2, 2197, when Venus again passes in front of Spica. The Sun passes a little more than 2° north of Spica around October 16 every year, and the star's heliacal rising occurs about two weeks later. Every 8 years, Venus passes Spica around the time of the star's heliacal rising, as in 2009 when it passed 3.5° north of the star on November 3.
A method of finding Spica is to follow the arc of the handle of the big dipper to arcturus, and then continue on the same angular distance to Spica. This can be recalled by the mnemonic phrase, "arc to Arcturus and spike to Spica."


The name Spica derives from spīca virginis "Virgo's ear of grain" (usually wheat). In Chinese astronomy, the star is known asJiao Xiu 1 (角宿一) in Jiau xiu, one of the chinese constellations.  Medieval names include Azimech, from Arabic السماك الأعزل al-simāk al-a‘zal 'the Undefended', and Alarph, Arabic for 'the Grape Gatherer'. Other titles include Sumbalet ("the corn ear", Arabic name for Virgo), Sombalet, Sembalet Eleandri, Shibbōleth, Citrā, Sa-Sha-Shirū, Kió, Repā.

>> Spica adalah bintang ke-15 yang paling terang di kegelapan langit malam, bintang ini terletak pada gugusan bintang virgo, sehingga menjadikan rasi bintang virgo sebagai salah satu rasi bintang yang paling mudah di temukan di dunia. Spica atau Alpha Virgin adalah bintang paling terang di rasi Virgo. Spica di percaya membantu Hipparchus meneukan sebuah kuil di Thebes yang menunjukkan bahwa kuil tersebut di bangun pada tahun 3200 sebelum masehi.




Source : http://earthsky.org/brightest-stars/speed-on-to-spica-the-15th-brightest-star



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L.N
August 27th 2014