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122. LEO is one of the most brilliant constellations in the winter hemisphere, and contains an unusual number of very bright stars. It is situated next E. of Cancer, and directly S. of Leo Minor and the Great Bear.
The Hindoo astronomer, Varaha, says, "Certainly the southern solstice was once in the middle of Asleha (Leo); the northern in the first degree of Dhanishta” (Aquarius). Since that time, the solstitial, as well as the equinoctial points, have gone backward on the ecliptic 75°. This divided by 504", gives 5373 years; which carry us back to the year of the world 464. Sir W. Jones says, that Varaha lived when the solstices were in the first degrees of Cancer and Capricorn; or about 400 years before the Christian era.
123. Leo is the fifth sign, and the sixth constellation of the Zodiac. The mean right ascension of this extensive group is 150°, or 10 hours. Its center is therefore on the meridian the sixth of April. Its western outline, however, comes to the meridian on the 18th of March, while its eastern limit does not reach it before the 3d of May.
This constellation contains 95 visible stars, of which one is of the 1st magnitude, one of the 2d, six of the 3d, and fifteen of the 4th.
"One splendid star of highest dignity,
124. The principal star in this constellation is of the 1st magnitude, situated in the breast of the animal, and named Regulus, from the illustrious Roman consul of that name.
It is situated almost exactly in the ecliptic, and may be readily distinguished on account of its superior brilliancy. It is the largest and lowest of a group of five or six bright stars which form a figure somewhat resembling a sickle, in the neck and shoulder of the Lion. There is a little star of the 5th magnitude, about 2° S. of it, and one of the 3d magnitude 5° N. of it, which will serve to point it out.
Great use is made of Regulus by nautical men, for determining their longitude at sea. Its latitude, or distance from the ecliptic, is less than ; but its declination, or distance from the equinoctial, is nearly 13° N.; so that its meridian altitude will be just
122. Describe Leo. Its situation? What remarkable statement of Varaha?
tions upon it? 123. and size of its stars? use made of Regulus?
Position of Leo in the Zodiac? When on the meridian?
equal to that of the sun on the 19th of August. Its right ascension is very nearly 150°. It therefore culminates about 9 o'clock on the 6th of April.
When Regulus is on the meridian, Castor and Pollux are seen about 40° N. W. of it, and the two stars in the Little Dog are about the same distance in a S. W. direction; with which, and the two former, it makes a large isosceles triangle whose vertex is at Regulus.
125. The next considerable star is 5° N. of Regulus, marked Eta, situated in the collar; it is of between the 3d and 4th magnitudes, and with Regulus constitutes the handle of the sickle. Those three or four stars of the 3d magnitude, N. and W. of Eta, arching round with the neck of the animal, describe the blade.
126. Al Gieba is a bright star of the 2d magnitude, situated in the shoulder, 4° in a N. E. direction from Eta, and may be easily distinguished by its being the brightest and middle one of the three stars lying in a semicircular form curving toward the west; and it is the first in the blade of the sickle.
127. Adhafera is a star of the 3d magnitude, situated in the neck, 4° N. of Al Gieba, and may be known by a very minute star just below it. This is the second star in the blade of the sickle.
128. Ras al Asad, situated before the ear, is a star of the 3d or 4th magnitude, 6° W. of Adhafera, and is the third in the blade of the sickle. The next star, Epsilon, of the same magnitude, situated in the head, is 24° S. W. of Ras al Asad, and a little within the curve of the sickle. About midway between these, and a little to the E., is a very small star hardly visible to the naked eye.
129. Lambda, situated in the mouth, is a star of the 4th magnitude, 31° S. W. of Epsilon, and the last in the sickle's point. Kappa, situated in the nose, is another star of the same magnitude, and about as far from Lambda as Epsilon. Epsilon and Kappa are about 41° apart, and form the longest side of a triangle, whose vertex is in Kappa.
130. Zozma, situated in the back of the Lion, is a star of the 3d magnitude 18° N. E. of Regulus, and midway between it and Coma Berenices, a fine cluster of small stars, 18° N. E. of Zozma.
131. Theta, situated in the thigh, is another star of the 3d magnitude, 5° directly S. of Zozma, and so nearly on the same meridian that it culminates but one minute after it. This star
125. Next principal star-size and position? 127. Adhafera? 128. Ras al Asad? Epsilon ? Of Kappa? 180. Of Zozma? 131. Of Theta? mentioned?
126. Al Gieba? How known? 129. Situation and size of Lambda ? What triangle? What other stars
makes a right-angled triangle with Zozma on the N. and Denebola on the E., the right angle being at Theta.
Nearly in a straight line with Zozma and Theta, and south of them, are three or four smaller stars, 4° or 5° apart, which mark one of the legs.
132. Denebola is a bright star of the first magnitude, in the brush of the tail, 10° S. E. of Zozma, and may be distinguished by its great brilliancy. It is 5° W. of the equinoctial colure, and comes to the meridian 1 hour and 41 minutes after Regulus, on the 3d of May; when its meridian altitude is the same as the sun's at 12 o'clock the next day.
When Denebola is on the meridian, Regulus is seen 25° W. of it, and Phad, in the square of Ursa Major, bears 39° N. of it. It forms, with these two, a large right-angled triangle; the right angle being at Denebola. It is so nearly on the same meridian with Phad that it culminates only four minutes before it.
Denebola is 35%1⁄2" W. of Arcturus, and about the same distance N. W. of Spica Virginis, and forms, with them, a large equilateral triangle on the S. E. It also forms with Arcturus and Cor Caroli a similar figure, nearly as large on the N. E. These two triangles, being joined at their base, constitute a perfect geometrical figure of the form of a Rhombus, called by some, the DIAMOND OF VIRGO.
A line drawn from Denebola through Regulus, and continued 7° or 8° further in the same direction, will point out Xi and Omicron, of the 3d and 4th magnitudes, situated in the foreclaws, and about 3° apart.
There are a number of other stars of the 3d and 4th magnitudes in this constellation, which require no description, as the scholar will easily trace them out from the map. The position of Regulus and Denebola are often referred to in the geography of the heavens, as they serve to point out other clusters in the same neighborhood.
According to Greek fable, this Lion represents the formidable animal which infested the forests of Nemæa. It was slain by Hercules, and placed by Jupiter among the stars in commemoration of the dreadful conflict. Some writers have applied the story of the twelve labors of Hercules to the progress of the sun through the twelve signs of the ecliptic; and as the combat of that celebrated hero with the Lion was his first labor, they have placed Leo as the first sign. The figure of the Lion was, however, on the Egyptian charts long before the invention of the fables of Hercules. It would seem, moreover, according to the fable itself, that Hercules, who represented the sun, actually slew the Nemean Lion, because Leo was already a zodiacal sign.
In hieroglyphical writing the Lion was an emblem of violence and fury; and the representation of this animal in the Zodiac, signified the intense heat occasioned by the sun when it entered that part of the ecliptic. The Egyptians were much annoyed by lions during the heat of summer, as they at that season left the desert, and haunted the banks of the Nile, which had then reached its greatest elevation. It was therefore natural for their astronomers to place the Lion where we find him in the Zodiac.
The figure of Leo, very much as we now have it, is in all the Indian and Egyptian Zodiacs. The overflowing of the Nile, which was regularly and anxiously expected every year by the Egyptians, took place when the sun was in this sign. They therefore paid more attention to it, it is to be presumed, than to any other. This was the principal reason, Mr. Green supposes, why Leo stands first in the zodiacs of Dendera.
In the Hebrew Zodiac, Leo is assigned to Judah, on whose standard, according to all traditions, a Lion is painted. This is clearly intimated in numerous passages of the Hebrew writings: Ex.-" Judah is a Lion's whelp; he stooped down, he couched as a
132. Size and position of Denebola? How known? When does it come to the meridian as compared with Regulus? What said of its meridian_altitude? When on the meridian where is Regulus seen? Phad? What triangle? How is Denebolo situated with respect to Arcturus and Spica Virginis? To Cor Caroli? What other large figures? HISTORY.-Greek fable? Egyptian? Hebrew Zodiacs? Scripture allusions to the
Lion, and as an Old Lion; who shall rouse him up?" Gen. xlix. 9. tribe of Judah hath prevailed." Rev. v. 5.
"The Lion of the
1. a LEONIS (Regulus)—A bright star with a distant companion; R. A. 9h. 59m. 51s.; Dec. N. 12° 44' 08". A 1, flushed white; B 8%, pale purple.
2. B LEONIS (Denebola)-A fine star with a distant companion; R. A. 11h. 40m. 54s.; Dec. N. 15° 28' 0". A 2, bluish; B 8, dull red.
3. y LEONIS (Al Gieba)-A splendid DOUBLE STAR; R. A. 10h. 11m. 08s.; Dec. N. 20° 39 0. A 2, bright orange; B 4, greenish yellow. A most beautiful object-binaryperiod supposed about 1000 years. Map VIII., Fig. 6.
4. LEONIS (Zozma)-A coarse TRIPLE STAR; R. A. 11h. 05m. 35s.; Dec. N. 21° 24' 1". A 3, pale yellow; B 13, blue; C 9, violet.
5. & LEONIS-A star with a distant companion in the mouth of Leo; R. A. 9h. 30m. 46s; Dec. N. 24° 30' 5". A 3, yellow; B 10, pale grey.
LEONIS-A BINARY STAR in the flank, 7° S. W. of Denebola (F on map); R. A. 11h. 15m. 35s.; Dec. N. 11° 24' 8". It forms a neat scalene triangle with ẞ and . A 4, pale yellow; B 7%, light blue; a beautiful object.
7. μ LEONIS (Ras Al Asad)-A DOUBLE STAR; R. A. 9h. 43m. 39s.; Dec. N. 26° 46′ 5′′. A 3, orange; B 10, pale lilac.
8. A neat DOUBLE STAR near Zozma; R. A. 11h. 05m. 17s.; Dec. 21° 00' 3". Components both 7%, and both faint yellow; a beautiful object.
9. A BRIGHT NEBULA near the hind paws; R. A. 10h. 57m. 37s.; Dec. N. 0° 49' 6". Large, elongated, well-defined-an enormous mass of luminous matter-one of a vast number of spherical nebulæ in the vicinity.
10. A bicentral WHITE NEBULA in the lower jaw, 2° south of 2 Leonis; R. A. 9h. 23m. 078.; Dec. N. 22° 12' 1". May be classed as double-small stars in field; difficult object. See Map VIII., Fig. 40.
11. A lucid WHITE NEBULA On the Lion's ribs, about 9° due east of Regulus; R. A. 10h. 35m. 31s.; Dec. N. 12° 31' 9". Round and bright, with two small stars in field. Another large pale white nebula, about 1° east of it.
12. A PAIR OF BRIGHT CLASS NEBULE in the Lion's belly; R. A. 10h. 39m. 49s.; Dec. N. 13° 28'. Found south of line joining Regulus and Leonis, about 10° east of, and nearly on a parallel with the latter.
13. A LARGE, ELONGATED NEBULA, with a bright nucleus on the Lion's haunch; R. A. 11h. 11m. 48s.; Dec. N. 13° 52′ 4′′; just 3° southeast of , with another smaller nebula, and several stars in the field. Map VIII., Fig. 41.
LEO MINOR (THE LITTLE LION).—MAP IV.
133. Leo Minor contains 53 stars, including only one of the 3d magnitude, and five of the 4th. The principal star is situated in the body of the animal, 13° N. of Gamma Leonis, in a straight line with Phad, and may be known by a group of smaller stars, a little above it on the N. W.
It forms an equilateral triangle with Gamma and Delta Leonis, the vertex being in Leo Minor. This star is marked with the letter l, in modern catalogues, and being the principal representative of the constellation, is itself sometimes called the Little Lion: 8° E. of this star (the Little Lion) are two stars of the 4th magnitude, in the last paw of Ursa Major, and about 10° N. W. of it are two other stars of the 3d magnitude, in the first hind paw.
"The Smaller Lion now succeeds; a cohort
Of fifty stars attend his steps;
And three, to sight unarm'd, invisible."
TELESCOPIC OBJECTS.-Alpha? Beta? Gamma? Point out on the map. Epsilon? Iota? Mu? What nebulæ ? Which shown on the map? Point out. 183. Describe Leo Minor? Its principal star? Helps form what triangle?
134. This constellation was formed by Hevelius, out of the Stella informes, or unformed stars of the ancients, which lay scattered between the Zodiacal constellation Leo on the S., and Ursa Major on the N. Its mean right ascension is the same with that of Regulus, and it comes to the meridian at the same time on the 6th of April.
The modern constellations, or those which have been added to our celestial maps since the adoption of the Greek notation, in 1603, are referred to by the letters of the English alphabet instead of the Greek. This is the case in regard to Leo Minor, and all other constellations whose origin is subsequent to that period.
A BRIGHT OVAL NEBULA between Lynx and Cancer, but given to Leo Minor; R. A. Sh. 42m. 44s.; Dec. N. 84° 00′ 6". Direct telescope 16° north by east of Presepe in Cancer.
SEXTANS (THE SEXTANT).—MAP IV.
135. Sextans contains 41 very small stars, including only one as large as the 4th magnitude. This is situated very near the equinoctial, 13° S. of Regulus, and comes to the meridian about the same time on the 6th of April. The other stars in this constellation are too small to engage attention. A few of the largest of them may be traced out from the map.
The SEXTANT, called also URANIA'S SEXTANT, is a modern constellation that Hevelius made out of the unformed stars of the ancients, which lay scattered between the Lion on the N., and Hydra on the S.
Urania was one of the muses, and daughter of Jupiter and Mnemosyne. She presided over astronomy. She was represented as a young virgin, dressed in an azurecolored robe, crowned with stars, holding a robe in her hands, and having many mathematical instruments about her.
A sextant, in mathematics, is the sixth part of a circle, or an arc comprehending 60 degrees. But the term is more particularly used to denote an astronomical instrument well known to mariners. Its use is the same as that of the quadrant: namely, to measure the angular distance, and take the altitude of the sun, moon, planets, and fixed stars. It is indispensable to the mariner in finding the latitude and longitude at sea, and should be in the hands of every surveyor and practical engineer. It may serve the purpose of a theodolite, in measuring inaccessible heights and distances. It may gratify the young pupil to know, that by means of such an instrument, well adjusted, and with a clear eye and a steady hand, he could readily tell, within a few hundred yards how far north or south of the equator he was, and that from any quarter of the world. known or unknown. This constellation is so called, on account of a supposed resemblance to this instrument.
1. A DOUBLE STAR on the right fore leg of Leo, though crimped into the sextant; R. A 9h. 45m. 45s.; Dec. N. 5° 41' 8". It lies about one-third of the way from Regulus to Alphard. A 7, and B. 9, both blue, and well-defined.
134. Origin of Leo Minor? Mean R. A.? What remark respecting the notation of the stars?
TELESCOPIC OBJECTS.-What nebula? Situation? How find? 135. Describe Sextans? Situation of its principal star? What said of the age of this constellation? Of Urania? instrument?
What said of the remainder?
TELESCOPIC OBJECTS.-What double stars? What nebula? What remarkable sight seen near this nebula?