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5. Rigel, at Jerusalem, on September 23rd.
7. At what time does Atair rise, culminate, and set at Jamaica on June 9th ?
and Hour, in any given Latitude.
1. Required the situation of the stars for the latitude of Newcastle, on October 6th, at 8 p.m.
The answer to this example constitutes
A SURVEY OF THE HEAVENS.
part of the heavens, is Capella, in the
tance from the horizon to the zenith.
of the 2nd magnitude, which form with
Bull's northern horn ; its distance from
Capella is more than 25°; its altitude not more than 5', and azimuth N. E. The general grouping of
the stars of this constellation forms a six-sided figure, as represented in the annexed figure.
The star Capella is easily distinguished by the acute angled triangle formed by 3 stars of the 4th magnitude, a little to the south of Capella, that bear the name of the Kids.
POLLUX CAEN CASTOR
If a line be drawn through the two stars that form the upper side of the triangle, and continued to the horizon, it will point out Castor, e, in Gemini, just rising ; azimuth, E.N.E.: it is between the Ist and 2nd magnitude. The other stars in this constellation have not yet risen ; but when they are above the horizon they form a tolerably correct paral. lelogram.
A line drawn between Castor and Capella, and continued higher in the heavens, will point out Perseus. It may also be easily found by directing the eye to the seven stars, and noticing the curved line which the principal stars in the constellation make from that point. Algenib, in the breast of Perseus, is a star of the 2nd magnitude. In the sword handle of Perseus is a beautiful cluster of stars, which a telescope of moderate power will display.
A little to the south of Perseus is the head of Medusa, which Perseus is holding in his hand. The brightest star in it is Algol, which is a variable star; its altitude is 33o; azimuth, E.N. E.; it is only 10° distant from Algenib.
Directly below the head of Medusa, about 14o above the horizon, are the Pleiades, or Seven Stars: they are situated in the shoulder of Taurus, and are so easily known, that no description is necessary. Aldebaran, a star of the 1st magnitude, which forms the eye of Taurus, is just rising; azimuth, E.N.E. A vertical circle, drawn through Algol, will point to it. There are 2 stars of the 3rd magnitude, and several smaller, very near Aldebaran, which form with it a triangle, or the letter V. The whole cluster is called the Hyades.
A line, drawn from Aldebaran through Algol, and continued to the zenith, will direct to Cassiopeia, or the Lady in the chair. This contains 5 stars of the 3rd magnitude, besides several of the 4th : it is in form something like the letter W, or, as some think, an inverted chair. It is situated above Perseus, within 30° of the zenith. The altitude of the brightest star, a, called Schedir, is 60°; azi
muth, E.N.E. Below Cassiopeia, and west of Perseus, is Andromeda, which contains 3 stars of the 2nd magnitude. A line from Algenib, parallel to the horizon, toward the south, will pass very near these 3 stars; and as they are all of the same magnitude, and placed nearly at the same distance of 150 from each other, they may easily be known. The name of the star nearest Perseus, and which is in the foot of Andromeda, marked, y, is Almaach: its altitude is 49°, azimuth, E.N.E. The
ARIES. name of B, in the girdle, is Mirach : its altitude 44°; azimuth, E. The altitude of a, in the head of Andromeda, is 46°; azimuth, E.S. E. The remarkable nebula, of which a figure is given, (p. 271,) is shown in the annexed engraving near the star marked »
About 18° below Mirach are two stars in Aries, not more than 50 distant from each other, forming with Mirach an isosceles triangle: the eastern star, a, is of the 2nd magnitude; the other, B, of the 3rd, attended by a smaller star, marked y, of the 4th magnitude. A line drawn from Mirach, perpendicular to the horizon, will pass between the two, and, besides, will point to a star of the 2nd magnitude, directly E., not 3° above the horizon.
This star is the first of Cetus, marked a, and is of the 2nd magnitude; it is named Menkar:--A line, drawn from Capella through the Pleiades, will also point to it. Cetus is a large constellation, and contains 8 stars of the 3rd magnitude; they all lie to the west of Menkar; B, a star in the tail, is more than 40° distant from it. The azimuth of Bis S. E. by E.; altitude nearly the same as that of Menkar.
The constellation Pisces is situated next to Aries; a number of small stars under the left arm of Andromeda form the most northerly fish, and an ellipse of stars below the wing of Pegasus, (as shown in the figure of that constellation,) constitutes the other. This constellation contains 1 star of the 3rd mag., marked a ;-its altitude is 10°: azi. muth, E. by S. : it is distant from Menkar 15o. A line drawn from Almaach, through a in Aries, will point to it.
If we return again to a, in the head of Andromeda, we shall find three other stars nearer the meridian, which, with it, form a very large square : these stars are in Pegasus, and are placed at the distance of
15° from each other; they are all of the 2nd mag. The 2 stars forming the western side of the square are called, the upper one Scheat, which is marked B, and which is in the thigh of Pegasus ; the under one, Markab, which is marked a, and which is in the wing: the lowest star in the eastern side of the square is in the tip of the wing, and is marked y. The altitude of Scheat is 55°; azimuth, S.E. | E. Altitude of Markab, 43° ; azimuth, S. E. by S. 1 E.
A line drawn through y and B, (the diagonal in the square of Pegasus,) and continued to the meridian, will point out Cygnus, a remarkable constellation, in the form of a large cross, in which there is a star of the 2nd magnitude, named Deneb, or Arided; it is marked a, and is almost directly upon the meridian, at the altitude of 80°. Cygnus