New- Star Chart For Cayman

A new feature as of June 2015 has been added - look at the bottom of this web page and there is a new Star Chart exclusively for Grand Cayman

January 11th 2008

Although the eye is drawn to bright Mars and the rising winter constellations, almost directly overhead as darkness falls is the small, faint constellation of Aries.
Aries is one of the least conspicuous of the zodiacal constellations, and has only two stars above third magnitude. These are Hamal and Sheratan, the Alpha and Beta stars of the constellation. Unusually, these two stars not only appear to be close together in the sky, but actually are: they lie just six light years from one another.
The Hipparcos satellite indicates that Hamal is about 65.9 light-years from Earth. Combined with its intrinsic brightness, this relatively small distance makes the star shine at an apparent magnitude of 2.01, the 47th brightest star in the sky.
Beta Arietis is the Ram's second horn. It also has the traditional name Sharatan (or Sheratan or Sheratim), and the Flamsteed designation 6 Arietis.
Al Sharatan means "the two signs", a reference to the star having marked the vernal equinox together with its binary partner Gamma Arietis several thousand years ago. It is 59.6 light years from Earth.
Gamma Arietis, Mesarthrim, shines third among the stars of the flat triangle that make the classical figure of Aries, the Ram (for that reason gaining the Gamma designation). The name (derived from Arabic) originally came from the same root as that for the Beta star, Sheratan (meaning "the two"), but was corrupted by mistranslations into its current form.
Gamma Arietis is a beautiful double star, which was discovered quite by chance in 1664 when astronomer, Robert Hooke, was following the motion of a comet. Gamma Arietis is one of the earliest double stars on record to have been found with the aid of a telescope.
Teegarden's star, a recent (2003) discovery is also in the constellation. It is one of Sun's closest neighbors at around 12 light years away. It appears to be a red dwarf, a class of low temperature and low luminosity stars. This would explain why it was not discovered earlier, since it has an apparent magnitude of only 15.4 (and an absolute magnitude of 17.47).
Teegarden's Star was discovered on images taken by the NEAT program operated by NASA. Its name comes from its principal discoverer, Dr. Bonnard Teegarden, an astrophysicist at NASA's Goddard Space Flight Center.
It is thought to be quite likely that many other dim and easily overlooked red dwarf stars exist in the nearest 20 light years, as stellar population surveys show their count to be quite lower than otherwise expected.
Although dim, Aries is one of the oldest and most revered of all constellations. The ancient Babylonians, Egyptians, Persians and Greeks all called this group of stars "The Ram." It is the Zodiac's first constellation since the Sun, at one time, was entering Aries on the day of the vernal equinox...the moment when it crosses from the southern to the northern half of the celestial sphere. However, because of the Earth's precession, the Sun is now in Pisces at the vernal equinox. Nevertheless, Aries is still considered to be the symbolic first constellation of the Zodiac and Right Ascension continues to be measured from the first point of Aries.
In a bygone age, the Egyptians associated Aries with Amon-Re, the ram-headed supreme Sun God who symbolized power and fertility. The Mesopotamians' name for the constellation meant a military leader or prince. In Hebrew tradition, the ram represented the death-defying blood of the lamb smeared on the doorways as part of the original Passover, which preceded the Hebrew Exodus from Egypt. The Greeks related Aries to the story of the Golden Fleece, the hide of the flying ram that Jason (with the help of his beloved Medea) spirited away from the serpent in the Grove of Aries. This constellation is mentioned in "Phaenomena," authored by the Greek poet Aratus, which dates from the Third Century B.C., and Ptolemy, the great astronomer who lived and worked in Egypt during the Second Century A.D., cataloged this constellation.
The present name of this Zodiac Sign is Roman in origin, Roman mythology having been adopted from that of the Ancient Greeks. This faint and tiny cluster of stars first appeared on monetary coin in 6 A.D.
clear skies

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