DOI Page / Citation link:
https://doi.org/10.11588/diglit.20131#0100
80
astronomical determinations of latitudes and longitudes.
Approximate
t == the Apparent Local Time, sought for, Avhich must be reduced by the Equa-
tion of Time to the Mean Local Time, and by the difference of Longitude
(which must be known within half or a quarter of a degree) to Greenwich
Time.
The differentiation of formula (la) shows, that we must take for h the lowest
observed altitude.
The following is an example of the mode of calculating:
Station No. 21. Baitlpi'ndi in the Panjab.
1856, December 3.'
Time by Chron. 3.................. 8h48m-7
Lowest Altitude reduced to the Sun's Centre . . 26° O'-O
Refraction....................... — l'-9
Parallax........................ -f- O'-l
True Altitude of Sun's Centre........... 25° 58'-2
Latitude North .......... 33° 6'
, Longitude E. Green. ... 73°-1 = 4h52'"
5 at Greenwich Mean Noon ............ — 22° 12'
log sin h = 9-641 log sin cp = 9-743 log cos 9 = 9-921
sin 7;. = 0-437 log sin 8 = 9-577„ log cos 8 = 9-967
— sincp sin&= + 0-209 9-320n 9-888
0-646"........................ log = 9-810
log cos t — 9-922
t = 33°-2 == 2h 12m-8
Time of observation by Chron. 3................ 8h48"1-7
Apparent Noon by Chron. 3................... 6'135'"-9
The observations used for the determination of
h m
Latitudes were made at........... 4 38-9
Mean Noon.................. 6 45-8
Mean Local Time of the observations . . .—2 6 • 9
Longitude E. Green.............. 4 52-1
Mean Greenwich Time............—6 59-0
Sun's Declination at Greenwich, Mean Noon, Dec. 3, — 22° 11' 32"
Horary Variation........— 21" • 2
log of Horary Variation..... 1 • 326n
log of 6h 59m expressed in hours 0 • 844u
"2-170~
nat. num = + 148" = +2' 28"
Sun's Declination at the moment of the observation — 22° 9' 4"
astronomical determinations of latitudes and longitudes.
Approximate
t == the Apparent Local Time, sought for, Avhich must be reduced by the Equa-
tion of Time to the Mean Local Time, and by the difference of Longitude
(which must be known within half or a quarter of a degree) to Greenwich
Time.
The differentiation of formula (la) shows, that we must take for h the lowest
observed altitude.
The following is an example of the mode of calculating:
Station No. 21. Baitlpi'ndi in the Panjab.
1856, December 3.'
Time by Chron. 3.................. 8h48m-7
Lowest Altitude reduced to the Sun's Centre . . 26° O'-O
Refraction....................... — l'-9
Parallax........................ -f- O'-l
True Altitude of Sun's Centre........... 25° 58'-2
Latitude North .......... 33° 6'
, Longitude E. Green. ... 73°-1 = 4h52'"
5 at Greenwich Mean Noon ............ — 22° 12'
log sin h = 9-641 log sin cp = 9-743 log cos 9 = 9-921
sin 7;. = 0-437 log sin 8 = 9-577„ log cos 8 = 9-967
— sincp sin&= + 0-209 9-320n 9-888
0-646"........................ log = 9-810
log cos t — 9-922
t = 33°-2 == 2h 12m-8
Time of observation by Chron. 3................ 8h48"1-7
Apparent Noon by Chron. 3................... 6'135'"-9
The observations used for the determination of
h m
Latitudes were made at........... 4 38-9
Mean Noon.................. 6 45-8
Mean Local Time of the observations . . .—2 6 • 9
Longitude E. Green.............. 4 52-1
Mean Greenwich Time............—6 59-0
Sun's Declination at Greenwich, Mean Noon, Dec. 3, — 22° 11' 32"
Horary Variation........— 21" • 2
log of Horary Variation..... 1 • 326n
log of 6h 59m expressed in hours 0 • 844u
"2-170~
nat. num = + 148" = +2' 28"
Sun's Declination at the moment of the observation — 22° 9' 4"