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Astronomical Occurrences

In JULY 1829.

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43

SOLAR PHENOMENA. The Sun enters Leo at 1 m. after 5 in the morning of the 23d of this month; and he rises and sets during the same period as in the following

TABLE
Of the Sun's Rising and Setting for every fifth Day.

July Ist, Sun rises 45 m. after 3, sets 15 m. after 8
6th

48
3 12

8
Ilth

52

3
8

8
16th

57

3

3
21st
3

57

7
26th

10
4 50

7
31st

17

4 Equation of Time. When it is required to regulate a clock or watch by means of a good sun-dial, add the following quantities to the time indicated by the dial, and the result will be that which should be given by the clock or watch at the same moment.

TABLE
Of the Equation of Time for every fifth Day.

Wednesday .. July 1st, to the time by the dial add 3 22
Monday

4 17
Saturday

...llth.......................... 5 3
Thursday
.16th.

5 37
Tuesday ....21st.

5 59
Sunday
.. 26th....

6 7
Friday .....31st......

6 1

m. s.

61h.........

LUNAR PHENOMENA.

Phases of the Moon.
New Moon .... Ist day, at 45 m. after 4 in the morning
First Quarter.. 9th........

.31.

6... Full Moon ...,16th.

2 in the afternoon Last Quarter .. .23d .........14........ 6 in the morning New Moon ....30th..

.39........ 5 in the afternoon

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Moon's Passage over the Meridian. The Moon will pass the first meridian at the fol. lowing times this month, when her transits may be observed, if the weather be favourable: viz.

July 9ih, at 12 m. after 6 in the evening
10th 57

6
Ilth 44

7 12th 34

8 13th 27

9 14th 23 .10 15th 21 ... .11 21st 1

4 in the morning 22d 53

4 23d 45

5 24th 37

6 25th 30

7 26th 22

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PHENOMENA PLANETARUM.

Phases of Venus. This planet continues almost wholly illuminated, but dim in appearance, on account of her great distance. July 1st { Dark ipated part = 11.75736

= Eclipses of Jupiter's Satellites. There will only be three of the eclipses of the first and second of these satellites visible this month, viz.

Emersions.
First Satellite ...12th day, at 31 m. 17s, after 10 at night

28th
Second Satellite, 31st 48 .. 49

9 Form of Saturn's Ring. Most of our readers are already aware, that the appearance of this ring is subject to vary from that

ight line across the disk of the planet to an elongated ellipse. The following is the proportion of the two axes at the commencement of this month; viz. July 1st { Conjugate axis =

50 ..

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= 1.000

-0.356 Z

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...28 ..

Conjunction of the Moon with the Planets and Stars.

July 1st, with Mercury ......at 5 in the afternoon

12th y in Libra. 5 in the morning
17th B.. Capricorn .. 4..
25th
g.. Taurus

.... 6 in the evening
25th ...18 .. Taurus 7..
25th

Taurus 8.
26th

Q.. Taurus ... l in the morning

Other Phenomena. Mercury will be in his iņferior conjunction at half past 3 in the afternoon of the 5th, stationary on the 16th, and attain his greatest elongation on the 26th, of this month. Venus and Mars will be in conjunction with each other at 5 in the afternoon of the 8th; and Venus and Saturn at the same hour on the 13th. Mars and Saturn will also be in conjunction at noon on the 19th. Georgium Sidus will be in opposition at half past 7 in the evening of the 27th. Jupiter will be stationary on the 29th; and Saturn will be in conjunction at 45 m. past 11 in the morning of the 31st.

On New, LOST, AND VARIABLE STARS.

(From the Literary Gazette.] Notwithstanding the attention of the mind of man has been, in all ages, ardently bending its intellectual powers in researches amidst the celestial regions, and of late years aided by the exquisite instruments which have enlarged the sphere of the fixed stars beyond all that could be conceived, it must be admitted that, notwithstanding these vast acquirements, we are but on the very threshold of the science of astronomy; and the conviction is pressed home to the mind, that, ere its flight be unfettered, and capable of expatiating through the vast range of the universe, the spirit must be released from its present enthralment, and arrayed in the vestments of immortality.

What is it we contemplate when we fix our eyes on the brightest of the starry train? a glittering „point, concerning which we only know that the body which sends forth such a stream of radiance is inconceivably too remote to borrow its lustre from the sun of our system, or from any other sun; for, of necessity, such a glorious orb, if existing, would be visible: we believe the star we thus behold to be itself a sun,-the fount of light, the soul and centre of revolving worlds: we know that, as far as human ingenuity has contrived instruments, the distance of this shining body is beyond computation; though such is the minuteness of modern instrumental graduation, that angles, formerly considered to be insensible, are now measured with the greatest accuracy. Where calculation fails, imagination takes up the wondrous consideration, and in vain attempts to date the period when this bright orb first shone forth in pristine beauty; and as we are ignorant of its origin, we are equally so of the period when the hand that moulded the orb shall return it to its original nothingness. When we survey the glorious host, 'stars densely thronging still,' we cannot suppose them merely twinkling lights to garnish the blue vault of heaven-to afford speculation to the philosopher-to excite the admiration, and add to the delight of man. Returning from the vast survey, we must confess that all these glittering gems, which are displayed in the celestial arches, are enshrined in mysterious obscurity: we see, admire, and speculate; but the soul falls prostrate in attempting to unravel these material wonders, whieh are as inexplicable as infinite space or eternal duration. We judge there are new creations, pure and beautiful, from the sudden appearance of new stars; unless we may suppose that their light, after having traversed space myriads of years, has just reached our earth: we may conclude, from the disappearance of others, that the awful mandate has been issued forth, and brilliant systems have been blotted from the ample page of the universe.

Among some which have been recently seen in the heavens, and are called New Stars, are those in the following constellations :-Lacerta, Perseus, Boötes, Hydra, Monoceros, Cepheus, &c.; and of those which have been termed Lost Stars, are three in Hercules, and others in Cancer, Perseus, Pisces, Orion, and Coma Berenices. A very remarkable star appeared in the year 1604, near the right foot of Serpentarius; it surpassed Jupiter in magnitude, and its brilliancy exceeded that of every other star: when near the horizon it shone with a white light; but in every other situation it assumed, alternately, the varying colours of the rainbow. It gradually diminished in splendour till about October 1605, when it disappeared, and has not been seen since.

There is also another class of stars in the heavens which afford considerable speculation to the philosopher. These are the Variable Stars, which, having attained a certain maximum of brilliancy, by degrees suffer a diminution of it, in some instances so as to vanish entirely, and re-appear, increasing to their former splendour; and this variation occupying a limited portion of time. Many have been the hypotheses to account for this periodical change: the solar spots sanction the idea that these stars are suns, having very large spots on their orbs, which, by their rotation, are alternately turned from and towards our system. Others have considered the phenomenon sufficiently explained, by supposing large planets circulating round the stars, which, when in conjunction, intercept the light. Another opinion is, that their exceedingly swift rotation generates a very oblate spheroid; and, consequently, when the plane which passes through the axis of the spheroid is turned towards our earth, the light appears at its minimum; and when its equatorial diameter is similarly posited, its maximum of brightness occurs. This shifting of the planes is accounted for from the action of immense planetary masses, whose orbits are considerably inclined. We have something analogous to this in the nutation of the Earth’s axis, which is caused by

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