Mail
NEW

Determination of left/right boundaries

1. By using the sun

1.1 Left boundary on back wall

(Date: Dec. 21^st, 1997)


Date	start/end time tape	start delay	time event	actual time	center sun	right side sun
15/12/97	14:31:49	00:00:20	00:10:09	14:42:18	214°58'	215°14'
15/12/97	15:16:49	00:00:00	-00:34:54	14:41:55	214°53'	215°9'
21/12/97	14:31:49	00:00:20	00:13:22	14:45:31	214°59'	215°15'
21/12/97	15:16:49	00:00:00	-00:30:42	14:46:07	215°6'	215°22'

The average sunset azimuth boundary (greenline, Line A) on left side off back wall is: 215°15' +/-5'

1.2 Right boundary on back wall

(Date: Jan 12^th, 1998)


Date	start/end time tape	start delay	time event	actual time	center sun	left side sun
12/1/98	14:53:49	00:00:20	00:36:40	15:30:49	223°13'	222°57'
12/1/98	15:31:49	00:00:00	-00:01:12	15:30:37	223°11'	222°55'
17/1/98	15:07:49	00:00:19	00:23:01	15:30:50	223°16'	223°0'
17/1/98	15:46:49	00:00:00	-00:15:59	15:31:10	223°11'	222°55'

The average sunset azimuth boundary (purpleline, Line B) on right side off back wall is: 222°57' +/-5'

Difference between left and right side boundary on back wall: 7°42' +/-10'

2 By using the model

Line B: 3°36' +/- 1'
Line A: 4°45' +/- 2'
Total difference: 8°21' +/- 4'
Line M (combining the figures from section1and this section): 219°40'+/-15'

Determination of horizon altitude

The azimuth of the horizon with Ward Hill is determined by three photographs:

a picture of the horizon made just in front of the entrance at Maeshowe (A)
a picture made from the back wall of the chamber towards the most southern azimuth viewable from within the chamber (B)
a picture made from the back wall of the chamber towards the most northern azimuth viewable from within the chamber (C)

Combining these three pictures gives an overview of the horizon with Ward Hill somewhere in the middle.

The purple and green lines are determined by modeling the positions oft he camera, the entrance location at D and S and the passage at respectively G₂ and H₂ (see also the overview of the mound).

Using the above picture between the green and the purple line, the altitude of the horizon as a function of the azimuth can be determined. In the below pictures one can see this altitude, which is used as input to the model of Maeshowe;

(100 pixels are equivalent with 1°)

Sunny days

The following days were more or less sunny at Maeshowe. The first three columns provide the date information and the following pair of colomns provide an approximation of the amount of sun on the back wall (0%: means sun behind clouds) for a specific days in the year:


# days before/after	Date	Date	1997	1997/1998	1998	1998/1999	1999	1999/2000	2000	2000/2001	2001	2001/2002
winter solstice	before	after	before	after	before	after	before	after	before	after	before	after
0	Dec. 21	Dec. 21	65%		0%		100%		0%
1	Dec. 20	Dec. 22	0%	0%	0%	0%	0%	0%	0%	0%
2	Dec. 19	Dec. 23	0%	0%	0%	2%	0%	0%	0%	???
3	Dec. 18	Dec. 24	0%	0%	0%	0%	0%	0%	100%	80%
4	Dec. 17	Dec. 25	1%	0%	0%	0%	0%	0%	???	100%
5	Dec. 16	Dec. 26	0%	30%	0%	0%	0%	0%	0%	0%
6	Dec. 15	Dec. 27	25%	75%	0%	80%	0%	0%	0%	0%
7	Dec. 14	Dec. 28	5%	0%	100%	0%	0%	0%	???	???
8	Dec. 13	Dec. 29	20%	80%	0%	0%	0%	0%	0%	???
9	Dec. 12	Dec. 30	0%	0%	100%	100%	10%	0%	0%	0%
10	Dec. 11	Dec. 31	0%	50%	0%	0%	0%	0%	0%	???
11	Dec. 10	Jan. 1	0%	0%	0%	0%	50%	0%	0%	???
12	Dec. 9	Jan. 2	0%	100%	0%	0%	0%	0%	0%	???
13	Dec. 8	Jan. 3	?	0%	0%	60%	0%	0%	0%	100%
14	Dec. 7	Jan. 4	?	25%	0%	0%	0%	0%	100%	0%
15	Dec. 6	Jan. 5	?	0%	0%	0%	0%	0%	100%	0%
16	Dec. 5	Jan. 6	?	0%	0%	0%	0%	45%	0%	???
17	Dec. 4	Jan. 7	?	0%	0%	10%	0%	0%	0%	0%
18	Dec. 3	Jan. 8	?	75%	50%	0%	0%	0%	100%	0%	0%
19	Dec. 2	Jan. 9	100%^+(?)	0%	0%	0%	0%	65%	0%	30%	50%⁺⁺
21	Dec. 1	Jan. 10	?	0%	100%^+(2min)	100%	0%	0%	0%	25%⁺⁺	0%
21	Nov. 30	Jan. 11	?	10%⁺⁺	0%	100%^+(1min)	?	0%	0%	0%	0%
22	Nov. 29	Jan. 12	?	100%	100%	0%	?	90%^{+(4 min)}	?	100%	0%
23	Nov. 28	Jan. 13	?	0%	?	0%	?	0%	?	100%	?
24	Nov. 27	Jan. 14	?	0%	?	0%	?	0%	100%	???	?
25	Nov. 26	Jan. 15	?	0%	?	0%	100%	0%	?	???	?
26	Nov. 25	Jan. 16	?	75%	?	0%	0%	0%	?	???	?
27	Nov. 24	Jan. 17	?	100%	?	0%	?	0%	?	0%	?
28	Nov. 23	Jan. 18	?	0%	?	0%	?	0%	?	0%	?
29	Nov. 22	Jan. 19	?	0%	?	100%	?	0%	?	0%	?
30	Nov. 21	Jan. 20	?	0%	?	0%	?	5%	?	0%	?
31	Nov. 20	Jan. 21	?	0%	?	0%	?	0%	?	?	?
32	Nov. 19	Jan. 22	?	0%	?	0%	?	0%	?	?	?
33	Nov. 18	Jan. 23	?	0%	100%	0%	?	0%	?	?	?
34	Nov. 17	Jan. 24	?	0%	?	0%	?	0%	?	?	?
35	Nov. 16	Jan. 25	^*	0%	?	0%	?	0%	?	?	?
36	Nov. 15	Jan. 26	?	0%	?	0%	?	0%	?	?	?

+ the sun flashed behind the right side of Ward Hill, the practical proof for my model (between brackets the duration of the reappearance).
++ although partly sun, no sun at a possible moment no reappearing.
* there was sun in the passage but not in the back wall! So between 33days before/after winter solstice (like Nov. 18^th, 1998) until 35 days before/after winter solstice (like Nov. 16^th,1997) the sun stops shining on the back wall.
? Not known.

Disclaimer and Copyright

Home

Mail

Major content related changes: Dec. 1, 2002