Page images
PDF
EPUB

aaa aaaaaaa

D. H.
July 1 10 A.M. ÞÓ
2 11 A.M.

in aphelion.
13 4 P. M. đ 0
21 6.4 AM
24 10 A.M.
27 5 A. M.

Leonis.
28 5.4 P.M. hoe
Aug. 9 3 A. M.

gr. elong. E. 270.4. 98 P. M. h stationary. 11 12.4 P. M. 19 1.2 A. M. 9 20 11.8 P. M. 21 21 3.3 A. M. 25 12.3 A. M. ho 29 3 A.M. h

31 1 P. M. o in
Sept. 5 12 P. M. § Ó inferior.

7.8 A.M.
17 1 P. M. 9 stationary.

3. 7 P.M.
19 1.8 P. M.
21 7.7 A.M.
21 1 P. M. 8 gr. elong. W. 180.
22 4 A.M.

gr. elong. E. 460 321 Oct. 8 12.2 A. M. o

11 8 A.M. 9o
13 6 P. M. 24
15 9.6 A. M. 270
16 11 A. M. * Ở

8 S. 21.
17 1 P. M. o
18 1.5 P.M. Ó
18 5 P.M. o
19 10
A. M.

superior.
22 8 A. M. P o 2
27

greatest brilliancy. Nov. 5 10.5 A.M. Ó

11 5 A.M. 9 stationary.
12 5.3 A, M, 24 Ở
15 6 A.M. h
15 12.1 P. M. o e
18 1 P. M. 8 oh
20 3 A. M. Ó 9. 8 N. 10 181.

24 3 A.M. Dec. 1 12 P.M.

inferior.
3 8.1 A. M.
3 4 P. M.

gr. elong. E. 210.2. 6 2 P.M.

10

[ocr errors]

ASTRONOMICAL PHENOMENA FOR THE YEAR 1898- Continued.

II.-PLANETARY CONFIGURATIONS.

(New York Mean Time.)

0.00 0.00 0 5

D. H.
Jan. 1 12 P.M. 9 in 8

2 8.2 A. M. O in perihelion.
6 11.2 A.M. ó o inferior.

eclipsed. 10

4.2 A.M. 13 10 A. M. 8 14 12.5 P.M. 24 17 12 P.M.

stationary. 18 1.7 P. M. h 20 7 P. M. o 21 4 P.M. 9 24 9 P.M. 21 stationary.

29 9.2 A.M. 8 gr. elong. W. 250, Feb. 4 8 P.M.

in aphelion. 10 5.5 P.M. 11

1.2 P.M. 8 14 11.9 P.M. h 15 5 P. M. 0 0 o superior, 18 7.9 P.M. 20

8.5 P.M. 90 Mar. 2 7 A.M. h

9 7.9 P.M. 21 ó 14 6. 7 A.M. hó 16 11 A. M.

superior. 19 8.2 P.M. Šo 21 2

stationary. 23 2.2 A.M. 9 OE 25 7 P.M. 28

26 9.2 A. M. * April 5 10.8 P. M. e 6 5 A.M.

gr.

hel. lat. s. 10 12.4 P. M. hó 10 11.2 P.M. 8 gr. elong. E. 190.5. 17 8.8 P.M. de 18 12.2 P.M. 20 9 P. M. 8 stationary. 22

6.6 A.M. 24 3 P.M. & in 30 4

o in perihelion. May 1 5.2A. M. * Ở inferior.

3 4 A.M. 48 7 6. 7 P.M. h 13 12 P.M.

stationary. 16 8. 4 P.M. Ó € 22 12.2 P. M. H 3 22 12.9 P. M. ở 27 9.2 P.M. 24 stationary. 28 6 A.M. 9 in perihelion. 28 9 A.M.

gr. elong. W. 250. 30 7 A. M. h 8

30 12 P. M. 4 E June 4 2.2 A. M. h

14 6.7 P. M. Šo
21 11 P.M.
22 11 A. M. 24 D
26 10.2 P. M. 216 €
27 3 A.M. 44 in aphelion,
30 2 A. M, 8 superior.

mom futuro to @+Mommo maso figo

1 A.M.
10 1 P.M. d stationary.
10 5 P. M. o
12 3.5 A.M.
12 4 A.M.

stationary.
12 9.5 P.M. hoe
20 6 A.M.

stationary.
21 5 P. M. * 0 0 inferior.
30 9.7 A.M. O E
31 3 P. M. in perihelion.

The Ancient and modern Year. THE Athenians began the year in June, the Macedonians in September, the Romans first in March and afterward in January, the Persians on August 11, the ancient Mexicans on February 23, the Mohammedans in July: The Chinese year, which begins early in February, is similar to the Mohammedan in having 12 months of 29 and 30 days alternately; but in every nineteen years there are seven years which have 13 months. This is not quite correct, and the Chinese have therefore formed a eycle of 60 years, in which period 22 intercalary months occur.

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][ocr errors][ocr errors][merged small][ocr errors][ocr errors][ocr errors][merged small][ocr errors][ocr errors][ocr errors][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][ocr errors][ocr errors][merged small][merged small][ocr errors][merged small][merged small][ocr errors][ocr errors][ocr errors][ocr errors][ocr errors][ocr errors][merged small][ocr errors][ocr errors]

Astronomical Constants. The mean obliquity of the ecliptic for the year 1898 is 230 271 8/1.96. Mean annual diminution, O. 46.

The present accepted value of the solar parallax is 81.81 at the earth's mean distance, which is 92,790,000 miles, with a probable error of about 75,000 miles more or less.

The eccentricity of the earth's orbit is 0.016771; we are therefore 3,112, 560 miles nearer to the sun at perihelion (January 1) than at aphelion (about July 1).

Length of the sidereal year, 365 days, 6 hours, 9 minutes, 9.6 seconds of mean time.

Length of the tropical year (from equinox to equinox), 365 days, 5 hours, 18 minutes, 46.07 seconds of mean time.

Mean distance from earth to moon, 238, 850 miles.
The length of a second's pendulum, that is, one which vibrates once in a second, in vacuo,

ASTRONOMICAL CONSTANTS- Continued, at any place whose latitude is l, is 39. 01254 +0.20827 sin: l inches. At New York it is 39.1013 inches.

The acceleration of gravity in one second of mean solar time is 32.086528 +0.171293 sinal feet. The half of this is the distance through which a body falls (in a vacuum) in one second.

The velocity of light is 186,330 miles per second.

Light requires 8 minutes and 18 seconds to pass from the sun to the earth when at its mean distance, as given above;

therefore, when we look at the sun we see him not where he actually is, but where he was about 8 minutes and 18 seconds ago; his true place is then always in advance of his apparent place.

Pole Star. MEAN TIME OF TRANSIT (AT NEW YORK) AND POLAR DISTANCE OF POLE STAR

[merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

A. M.

sin p

E, M.S.OI IH, M.S. OIH. M.8. OI! H.M.S.

H.M.S. O 1 11 ||H, M 8. O I II
A. M.
A. M.

P. M.

P. M. 16 41 35 1 14 16 4 49 11 1 14 11 9 40 44 1 14 8 19 43 3 1 13 53 10 37 16 1 13 41 8 39 71 13 89 116 9 24 1 14 14

1 14 9 2 1 39 1 14 0 12 3 46 1 13 49 9 57 55 1 13 38 7 59 41 1 13 29 911 593 16 1 14 13 1 3 93 50 1 14 7 1 29 17 1 13 57 11 20 32 P.M. 1 13 46 9 18 39 1 13 34 7 20 141 1 13 97

From June 16 to August 1 both the upper and lower transits take place during daylight. The azimuth at the time of greatest eastern or western elongation can be easily computed from the formula:

sin A =

cOS 1 where A denotes the azimuth, p the polar distance, I the latitude of the place.

DATE OF GREATEST ELONGATION. To find the time of greatest eastern or western elongation, let H denote the hour angle, and I and p as before, then we shall have

cos H= tan p tan l. And the hour angle in mean time is

Hm= Ho X 0-0664846. This quantity, Am, added to or subtracted from the time of transit given above, according to the elongation required, will give the mean time of the greatest elongation at any place whose north latitude is l.

Star Table.
FOR IDENTIFYING THE PRINCIPAL FIXED STARS

[blocks in formation]

Upper. Lower.

Upper.

Lower. H. M. H. M.

0 1

H. M. H. M. aAndromeda..

N 28 31 1 18.0 +10 40.0 a Leonis (Regulus). N 12 28 + 8 40.1 +20 88.1 y Pegasi (Algenib) N 14 37 1 18.2 +10 44.8 a Virginis (pica). S 10 37 H+11 56,5 +23 54,6 eCassiopeiæ..

N 56 58 - 0 42.3 +11 15. 8 a Bootis (Arcturus). N 19 43 +12 47.5 + 0 45.5 Arietis N 22 59+ 0 40.0 +12 38.0 BUrsæ Minoris..

N 74 85 +13 27.5 + 1 25.5 8Persei (Algol).. N 40 34 + 1 39.9 +13 37.9 aCoronæ Borealis.. N 27 4 +13 49.7 + 1 47.7 a Tauri (Aldebaran) N 16 18 3 8.2 +15 6.2 aScorpi (Antares) $ 26 12 1+14 59.8 + 2 57.3 Agrigæ (Capella). N 45 54 3 47.1 +15 45.1 (Lyra (Vega)

N 38 41 +17 9.3 + 5 7.3 Orionis (Rigel). S 8 19 + 3 47.6 +1E 45.6 a Aquilae (Altair).

N 8 36 +18 21.4 + 6 19.4 Orionis (Betelguese). N 7 23 + 4 27.6 +16 25.6 aCygni (Deneb). N 44 55 +19 13.5 + 7 11.5 aCanis Majoris (Sirius). S 16 35 + 5 18.4 +17 16.4 aCephei

N 62 9 +19 61.5 + 7 49.5 Gerninurum (Castor) NJ 7 6 5.7 +18 3.7 | Aquarii

S 0 49 +20 85.8 + 8 33.8 BGeminorum (Pollux).. N 28 16 + 6 16.6 +18 14.6 a Piscis Aus.

S 30 10 +21 27.1 + 9 25.1 GCanis Minor........ N 529 + 6 11.6 +18 9.6 la Pegasi (Markab). N 14 39 + 34.7 + 9 32.7

To find the time of the star's transit add or substract, according to the sign, the numbers In the second column of figures to the date of the transit of the pole star given above. Thus, for a Andromedæ February 1st Lower Transit of Polar Star is 4 h. 34.9

m. A. M., to which add 10 h. 40 m. and we have 3 h. 14.9 m. P. M.; for December 1st, we find 7 h. 21.1 m. P, M., etc.

The Moon's Phases, 1898.

Boernos

BOSTON.

NEW YORK. WASHINGTON. CHARLESTON.

[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]

1 49 a. 4 51 P. 8 14 A. 12 29 P.

Fans

[ocr errors]
[ocr errors]

9 27 A.

[ocr errors]

ఊరిలు

11 35 P. d 12 10 A.M. 26 11 58 P.

M.

[ocr errors]
[ocr errors]

CONTA

[ocr errors]

1898.

thane

Day.

CHICAGO.

P. M.

Last Quarter.

Phase. Full Moon. Last Quarter. New Moon. First Quarter. Full Moon. Last Quarter. New Moon. First Quarter. Full Moon. Last Quarter. New Moon. First Quarter. Full Moon. Last Quarter. New Moon, First Quarter. Full Moon. Last Quarter. New Moon. First Quarter. Full Moon. Last Quarter. New Moon. First Quarter. Full Moon.

February. | January.

ܘܗܝܙ

March.

3 29

April.

4 30 PM 8 14 P. M.

May.

సలస கலக்க

June.

P. M.
P. M.

July.

CONE

New
First Quarter.

ܚܘܝܕܕ

A, M.

August,

Full Moon.

Last Quarter. New Moon. First Quarter. Full Moon,

Coward

1600

ܝܕܗܟge

WOO

张见生必0

6 6 PM

Last Quarter. New Moon. First Quarter. Full Moon.

ག“g

P.
6 26 P.M.

PHB%

งงง

25 AM 7 34 A.

NANO

Fఅణ

December November October. Septemb’r

团以

Foto

นี้

CA

adam

M 6 65 P. M.

6 31 PM

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][graphic][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

EXPLANATION. –The white spaces indicate the amount of moonlight each night. Thus, January 7,
February 6, etc., the time of full moon, when for two or three nights in succession moonlight lasts
all night;January 14, February 13, etc., when the moon rises at or near midnight or when the latter
half of the night has moonlight; January 22, February 20, etc., the time of new moon, when for two
a three nights there is no moonlight; January 29, February 28, etc., when the moon sets at or near
midnight, or when the former half of the night has moonlight.

« PreviousContinue »