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Astronomical Occurrences

In OCTOBER 1823.

SOLAR PHENOMENA. The Sun enters Scorpio at 19 m. after 5 in the morning of the 24th of this month; and he rises and sets during the same period in the following

TABLE Of the Sun's Rising and Setting for every fifth Day. October 1st, Sun rises 11 m. after 6. Sets 49 m. after 5 6th, ............. 22

.. 22 .......... 6 ......... 38 ......... 5 Ilth, ............ 32

.......... 6

......... 28
16th, ............ 41 ......... 6
21st, ............

51 ......
26th, ............ 1 ........... 7 ......... 59 ......... 4
31st, ............. 11 ......... 7 ......... 49 .......... 4

Equation of Time. If the following numbers be subtracted from the time as indicated by a good sun-dial, the remainders will be what should be shown by a well regulated clock at the same instant.

TABLE
Of the Equation of Time for every fifth Day.
Wednesday, Oct. Ist, from the time by the dial subtract 10 8
Monday,......... 6th, ............................................. 11 40
Saturday, ....... 11th,

...........................................18 2
Thursday, ... 16th,

14 13 esday, ......... 21st,

15 10 Sunday, ......... 26th,

15 50 Friday, ......... 31st,

16 12 LUNAR PHENOMENA.

Phases of the Moon.
New Moon, 4th day, at 41 m. past 8 morning
First Quarter, 12th .......... 7 ........... 2 ............
Full Moon, 19th ......... 11 ........... 10 at night
Last Quarter, 26th ......... 44 ............ 7 evening.

Moon's Passage over the Meridian. The following times of transit are selected as affording suitable opportunities for observation during this month: viz.

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October 10th, at 6 m. after 5 in the evening

11th, ... 56
12th, ...

13th,

14th, 15th,

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26th,

6 ...

16th,

9 at night 17th,

10 .......... 18th, ...

11 ........

5 in the morning
27th,
28th,
29th, ..

30th, ...
PHENOMENA PLANETARUM.

5. Phases of Venus. This planet still continues to decrease, and will totally disappear in the early part of this month, for on the 1st it will only appear in the telescope like a very narrow faint crescent. October 1st,

ist s Illuminated part = 0.36847 digits verover ist, Dark part ........ = 11.63153

Eclipses of Jupiter's Satellites. Both this and the following months afford the young astronomer some fine opportunities of observing these phenomena. The following are those that are visible this month: viz.

Immersions. ,
First Satellite, 3d day, at 28 m. 82 s. after 5 in the morning

4th ......... 56 ... 50 ......... 11 at night
12th .........

1 in the morning 19th .........

3 20th ........

10 at night 26th .........

in the morning
28th ......... 5 ... 9 ..........
Second Satellite, 3d day, at

10th ......... 47 ... 19.
..... 17th ......... 23 ... 36 .........

Form of Saturn's Ring. This phenomenon will exhibit a considerable opening this month, as the following will be the proportion of its axes: viz.

the sot Transverse axis 1.000
October 1st, { Conjugate axis – 0.443

. .
.

1st

h. m.

h. m.

5 47

TABLE · Of the Meridional Transits and Altitudes of the

Planets. 7th 13th 19th 25th

TRANSITS. h. m.

h. m. h. m. Mercury 1 29 aft. 1 16 0 48 04 11 21 mor. Venus 04 aft. 08 11 35 mor. 111 10 33 Mars 8 46 mor. 8 39 8 31 8 22 8 13 Jupiter 6 16 mor. 5 56 5 35 5 14 4 53 Saturn 3 O mor. 2 37 2.14 1 50 1 26 G. Sidus 6 9 aft.

5 22 5 0 4 39

ALTITUDES. Mercury 230 24

220 41 23010 26049 310 3 Venus 22 21

23 43 26 17 28 9 30 21 Mars 55 51 54 48 53 44 52 37 51 29 Jupiter 61 21

61 19 61 18 61 17 61 17 Saturn 54 46

54 41 54 35 54 28 54 21 G. Sidus 14 53

14 52 14 52 14 51 14 51

Other Phenomena. Georgium Sidus will be in quadrature at 45 minutes past 4 in the afternoon of the 1st of this month, and Jupiter at a quarter after 1 in the morning of the 4th. On the 8th there will be an occultation of the bright star a in Scorpio by the Moon. The Immersion will take place at 24 m. 30 s. after 4, and the Emersion at 44 m. 30 s. past 5, in the afternoon. At the former instant, the star will be 21 north of the Moon's centre, and at the latter it will be t' south of the same point. Mercury will also be stationary on that day, and in his inferior conjunction at half past 4 in the morning of the 20th. Venus will be in conjunction on the 10th, at 45 m. after 10 at night; she will, of course, be wholly invisible at this time. The Moon will be in conjunction with Georgium Sidus at 34 m. after 5 in the morning of the 11th ; with Jupiter, at 7 m. past 5 in the morning of the 25th ; and with Venus at 22 m. past 2 in the afternoon of the 31st. Mars will be in conjunction with a in Leo on the 20th, the planet being at that time 61' north of the star. Jupiter will likewise be stationary on the 28th, and Mercury on the 29th.

It may be remarked here, that, in the Shetland Isles and the northern parts of Europe, the Aurora Borealis often makes its appearance this month, and though not a celestial, it is an atmospherical phenomenon, which has long attracted the attention both of philosophers and poets. While the former, however, have been unable to ascertain its nature, the latter have succeeded in giving beautiful descriptions of its appearance. Among these, Thomson thus admirably delineates its vivid playfulness :

Silent from the north
A blaze of meteors shoot: ensweeping first
The lower skies, then all at once converge
High to the crown of Heav'n, and all at once
Relapsing quick, as quickly reascend,
And mix and thwart, extinguish and renew,
All ether coursing in a maze of light,

REFLECTIONS ON THE STARRY HEAVENS.

[Continued from p. 271.] Having presented a brief description of the two signs which supply us with ready means of distinguishing the northern point of the heavens, and consequently of determining all the cardinal points of the compass, we shall offer a few observations on the Zodiacal Signs, which are so repeatedly mentioned in the course of our Astronomical Occurrences. The first of these is

ARIES (), the Ram. Aries is the first of the Zodiacal Signs, and which, according to the reckoning of astronomers, who adopt the fixed and intellectual zodiac of Hipparchus, the Sun enters at the commencement of the vernal equinox, which is on the 20th of March, astronomical time. This is the beginning of the astronomical year: it is also from this point that the right ascension of the stars and the longitude of the heavenly bodies are computed. When the Sun enters this sign, he rises to the north pole, and the shadows of night begin to envelope the opposite point of the heavens. The Earth at this time is in that part of its orbit which answers to the beginning of Libra, and consequently the Sun, which is seen in the opposite point, appears to be entering Aries. He is then vertical to the equator, and the circle which terminates light and darkness passes through the poles, and, cutting the equator and all its parallels at right angles, causes night and day to be equal in all parts of the globe, except the poles.

On this sign, and in reference to the preceding statements, Mr. Jamieson makes the following judi. cious and instructive remarks, at page 35 of his Celestial Atlas.-" These are astronomical truths; but in nature the sign Aries has no part therein, its place being occupied by Pisces. More than 2000 years have passed away since the sign Aries, owing to the precession of the equinoxes, has ceased to open the astronomical year, as Princeps signorum et Ductor exercitûs Zodiaci. In more remote times, the vernal equinox took place, and the year opened when the Sun was in Taurus. But when astronomers and legislators agreed to reform the Calendar according to the new style, the Ram, with which the year commenced, was called Jubel--the Jubelee was proclaimed and the New Year adopted. Herodotus tells us that once a year, on a certain day, at the festival of Jupiter Ammon, or the Sun in Aries, the people of Thebes, in Egypt, slew a ram. The Sun came into Aries on the 10th of the Jewish month Nisan. An annual feast was then celebrated, and a male ram was slain, to commemorate the deliverance from Egypt. At the period of the flight from Egypt, the vernal equinox took place when the Sun was in Aries.

« The Greeks derive the symbol of this sign from the ram which produced the golden fleece that Jason brought from Colchis, about 1263 years before the Christian era. Popular opinion, however, traces

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