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Category Archives: Stars
Spica: the Wheat Sheaf
The name Spica comes from Latin, meaning “ear of wheat”. It is the brightest star in the constellation Virgo, which rules the harvest season. Continue reading
Canopus: the brightest star you’ve never heard of
Ever since I wrote a post on Polaris, I have been wondering, is there a south pole? Sadly, there isn’t, not really.
There are two candidates for a south pole star. By 14 000 CE Canopus will, because of the wobble in the earth’s axis, be as close as it will ever get to being the South Pole, about 10° from magnetic south. The other, Sigma Octanis in the Octant, is the closest star at present. The Southern Cross points to where a south pole would be, and like Ursa Minor is a circumpolar constellation, so it’s always above the horizon.
Deneb: swan’s head
Like the eagle in Aquila, the swan is a bird with many associations, so it seems logical to put a swan in the sky. It was Venus’ bird; the Romans sometimes called the constellation Myrtilus because of this, myrtle also being Venusian.
Altair: the Eagle
Eagles and thunder-gods often appear together, but in Greek myth the eagle was Zeus’ accomplice as well as his emblem. It stole the beautiful youth Ganymede from his fields and carried him to Olympos to be Zeus’ cupbearer. (Ganymede is also in the heavens, as the constellation Aquarius.)
The eagle also carried out Zeus’ punishment of Prometheus, who stole fire to give to the humans. Zeus had him chained to a cliff face, and the eagle came every day and tore out his liver. Hercules rescued Prometheus as part of his 11th Labour and killed the eagle. Zeus then put it in the sky to reward its faithful service.
The Eagle features among the Hercules family of constellations, by the way, which include large asterisms like Ophiuchus the Snake-Handler as well as tiny ones like Ara, the Altar.
Vega: the jewel in the Harp
Vega is the fifth brightest star in the sky, a brilliant blue-white star two and a half times larger than the sun. It takes turns with Polaris and Thuban as the pole star, and will be the nearest star to the celestial north pole again in 14 000 AD.
Aldebaran: the Bull’s Eye
As you can see from the picture above, Aldebaran is the bull’s left eye, and the brightest star in Taurus. It appears ruddy through a telescope, suggesting that Taurus is an angry bull. The V-shape of the bull’s face, known as the Hyades, makes it easy to find.
The Arabic name reflects its position: the Follower, since it rises after the Pleiades, the stars that make up the bull’s shoulder. It is primarily a winter star, and by now will be visible in the sky around dawn.
Fomalhaut: the Fish’s Mouth
Fomalhaut was one of the four year-stars. Since the other three belong to the “fixed” astrological signs Taurus, Leo and Scorpio, Fomalhaut is assumed to be associated with Aquarius, the fourth fixed sign. It can be seen low in the southern sky in the fall, and can be seen due south around 11:00 p.m. in early October.
Antares: the scorpion’s heart
The main star in Scorpio is the 15th brightest star in the sky. Its name means “Rival of Ares” or “Equal to Ares”, because of its brightness and red colour. And its size – Antares is a red supergiant, 3 000 times the size of our sun. (If we switched our sun for Antares, its bulk would extend out to Mars.) A clould of reddish metallic dust surrounds it, five light years in diameter, which makes it look even larger in the night sky.
Arcturus: Bear-Guard
Arcturus is an orange giant, and the fourth brightest star in the sky. Its moment of earthly fame came during the Chicago World Fair of 1934. There had been a World Fair in Chicago in 1893, and they calculated that light leaving Arcturus then would arrive in time for the new Fair.*
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