The
57th numbered star in the Nautical Almanac, and the last on the primary
list is Alpha Pegasi, also called Markab. Markab is a third magnitude
star.
The nomenclature of Markab would take Alan Turing to decode:
First, despite being the Alpha star in Pegasus, Markab is only the third brightest star in the constellation Pegasus The Winged Horse.
Second, Markab means "saddle," but is usually translated as "shoulder" due to its position in the constellation.
Third, it should not be mistaken for Markeb, a star in the constellation of Velorum The Sail. It should also not be confused with its mate Tau Pegasi, also listed as Markab in some almanacs.
Fourth, it is one of the four stars that make up the asterism of The Great Square (which lies within Pegasus much as the Big Dipper lies within Ursa Major). The other three stars of the Great Square are Scheat, Algenib, and Alpheratz --- only Alpheratz is in another constellation, Andromeda (but has official designations in both).
Fifth, Alpheratz used to be Scheat when Scheat was Markab and Markab was Menkib. The stars of the Great Square have had their names shuffled since antiquity.
Sixth (bonus), Algenib is the name of two separate stars in different constellations, the similar-sounding adjoining Pegasus and Perseus.
Now that we are all utterly confused, yes, this will be on the test.
Today's Markab is a blue subgiant star that shows every physical and spectroscopic indication that it is about to leave its Main Sequence and expand into a red star. Its exact age in years is undetermined. Markab is 3.1 times the mass and 4.72 times the radius of the Sun. Its temperature is just over 17,000 degrees F. It is 205 times as luminous as the Sun, and its distance is 133 light years from the Sun.
The nomenclature of Markab would take Alan Turing to decode:
First, despite being the Alpha star in Pegasus, Markab is only the third brightest star in the constellation Pegasus The Winged Horse.
Second, Markab means "saddle," but is usually translated as "shoulder" due to its position in the constellation.
Third, it should not be mistaken for Markeb, a star in the constellation of Velorum The Sail. It should also not be confused with its mate Tau Pegasi, also listed as Markab in some almanacs.
Fourth, it is one of the four stars that make up the asterism of The Great Square (which lies within Pegasus much as the Big Dipper lies within Ursa Major). The other three stars of the Great Square are Scheat, Algenib, and Alpheratz --- only Alpheratz is in another constellation, Andromeda (but has official designations in both).
Fifth, Alpheratz used to be Scheat when Scheat was Markab and Markab was Menkib. The stars of the Great Square have had their names shuffled since antiquity.
Sixth (bonus), Algenib is the name of two separate stars in different constellations, the similar-sounding adjoining Pegasus and Perseus.
Now that we are all utterly confused, yes, this will be on the test.
Today's Markab is a blue subgiant star that shows every physical and spectroscopic indication that it is about to leave its Main Sequence and expand into a red star. Its exact age in years is undetermined. Markab is 3.1 times the mass and 4.72 times the radius of the Sun. Its temperature is just over 17,000 degrees F. It is 205 times as luminous as the Sun, and its distance is 133 light years from the Sun.
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