Rendezvous with Birr Castle: A Visit to the Heart of Early Irish Astronomy Ron Buta

1
Rendezvous with Birr Castle A Visit to the Heart
of Early Irish AstronomyRon Buta
2
(No Transcript)
3
History

• Prior to 1620, castle belonged to OCarrolls
• granted to Parsons family in 1620 by the Crown
• continuous occupation since then
• family famous for work in astronomy, photography,
  engineering, and botany
• 3rd earl started with 36-inch
• built 72-inch to see if nebulae would resolve

4
Statue of 3rd Earl, central Birr
5
(No Transcript)
6
The spirals were the biggest discovery the 3rd
Earl made at Birr Castle.
7
The 3rd Earls son, Laurence, was the first to
accurately measure the temperature of the Moon.
8
7th Earl of Rosse, William Brendan Parsons
9
Published by Cambridge University Press, February
2007
Gerard de Vaucouleursborn April 25, 1918 Paris,
Francedied October 7, 1995 Austin, Texas
10
Main annual Irish star party
Deirdre Kelleghan, president of Irish
Astronomical Society
11
Demesne refers to the land associated with the
castle.
12
Layout of the Demesne
13
(No Transcript)
14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
The telescope is generally stowed pointing south.
It could only observe objects within a limited
angle around the meridian. A 72-inch f/9
reflector having a focal length of 54 feet!
21
One of two ladders for lifting the lower viewing
platform.
22
Taoiseach prime minister of Ireland TDmember of
Irish parliament John Bruton served 1994-1997
23

• Upper observing platform

24
This shows that a real mirror is installed!
25
Changing eyepieces meant sliding the large one to
the right.
26
Eyepiece area

• The telescope had no finderscope. The
  original wide-field eyepiece was the finder. It
  had a field of view of 31 arcminutes and a
  magnification of 216X. A popular 1/2 inch
  eyepiece gave a magnification of 1300X.

27
Mary Rosse photo of her children and their nurse.
Details of original eyepiece region.
28
Mary Rosse photo of old eyepiece assembly
29

• A scale for east-west movement of the telescope.

30

• Wooden supports for lower observing gallery.

31
An outside mechanism for lifting the lower
observing gallery.
32
Side view of windlass
33
Counterpoise and horns to the north
34
spider beam to run lifting chain
35

• Rear of telescope showing large mirror box.

36
(No Transcript)
37
(No Transcript)
38
These are supports for the upper observing
gallery and probably slid back and forth to
adjust to the eyepiece position.
39

• Stairwell to the upper observing gallery.

40
One of two chains involved in lifting lower
observing gallery.
41
(No Transcript)
42
This 1860 Mary Rosse photo shows the lower
gallery assembly lifted to reach the eyepiece.
43
A gantry operator would stand near this platform,
as shown at right.
44
Schematic of optical and pivot design of the
Leviathan.
45
(No Transcript)
46
(No Transcript)
47
Original speculum metal mirror, 6ft in diameter,
5 thick, and weighing 3 tons. Middle sitting
Otto Boeddicker, last Birr Castle astronomer.
48
Mirror would be rolled on a trolley and installed
in mirror box when tube pointed to zenith.
49

• Close-up view of mirror box.

50

• Rail used to move mirror in and out of its box.

51
This is how the mirror was taken to and from the
telescope on a small trolley.
52
This is a model of the device used to grind and
polish the mirror.
53
Windlass drum for moving the telescope. This
wound a chain attached to the mouth of the tube
passing over a high pulley, and was operated by
two assistants.
54
The universal joint was a cast iron pivot at the
base of telescope that provided two axes for the
tube to rotate around east-west and north-south.
55
(No Transcript)
56
(No Transcript)
57
(No Transcript)
58
(No Transcript)
59
(No Transcript)
60
(No Transcript)
61
(No Transcript)
62
(No Transcript)
63
(No Transcript)
64
(No Transcript)
65
(No Transcript)
66
The Visual Astronomy of Birr Castle

• Visual discoveries
• spiral, ring, and bar structures
• bar ansae
• dust lanes
• numerous novae, or new nebulae
• many previously unrecognized double nebulae

67

• The assistant observers at Birr Castle 1848-1878

68
(No Transcript)
69
The observing notebooks.
70
(No Transcript)
71
An original eyepiece.
72
(No Transcript)
73
NGC 1012
NGC 68, NGC 693, NGC 972
NGC 1068, NGC 1514
NGC 1023
NGC 1579
NGC 1637
74
Page from NGC showing LdR discoveries near NGC 68
75
NGC 2245, 2316-7, 3184, 3395-6
NGC 3187-90-93, 3627, 3953
NGC 4038-39, 4051, 4151-56
NGC 4303, 4389, 4485-90
76
NGC 4490 KPNO outreach
NGC 4490 36-McD visual
NGC 4490 LdR
77
NGC 4536, 4618-25, 4656-57/4710
NGC 5112, 5248, 5378
NGC 6058/5857-59, 6205, 6905
78
NGC 6946, 7008, 7177
NGC 7331, 7662
NGC 7678, 7814
79
One of the best and most accurate drawings made
at Birr Castle M101 (S. Hunter)
80
M101 S. Hunter 1861 (LdR)
M101 30 McD
M101 Block
81
lt----NGC 604
M33 knots
82
M33 B-band 3 Televue
M33 36-McD visual
Resolved supergiants in M33
IC 139-40 star cloud 36-McD NGC 604
82-McD
83
M51
M99
1850 P. T.
84
M51 30-inch McD visual
M51 S. Hunter 1864 Birr Castle
M51 KPNO outreach website
85
NGC 2371-72, 4627-31
M65, NGC 2261
NGC 5866, M97
86
M97 36-McD visual
M97 outreach website (White)
Birr Castle (LdR)
87
NGC 3893
NGC 3938
88
NGC 3893 36-McD visual
NGC 3893 Uminski
NGC 3893 LdR 1857
89
M1 36 McD visual
M1 internet image
M1 LdR (R. J. Mitchell)
LdR, P.T. 1844
90
NGC 4900 36 McD visual
NGC 4900 de V Atlas B-band
NGC 4900 LdR, bar with ring!
91
NGC 4725 30 McD, visual
NGC 4725 de V Atlas
NGC 4725 LdR 1858
The centre itself is like an extended nebula
with Nucl. enveloped in an irr ring or rings
somewhat like an anchor
92
NGC 4151 30 McD visual
NGC 4151 KPNO outreach
NGC 4151 LdR sketch, showing the ansae
93
M27 20-inch Obsession visual
M27 APOD
M27 1850 P. T.
M27 P.T. 1861
M27 48-inch visual Lassell 1866
Birr Castle
94
Orion Nebula
KPNO outreach image (Steinbergs)
McDonald 30-inch visual March 1979
Birr Castle drawings
95
Not observed at Birr Castle but would have been
interesting
96
NGC 2070 CTIO 36-inch visual September 1981
NGC 2070 ESO VLT BVR composite early 2000
97
NGC 2403 KPNO outreach
NGC 2403 30-McD visual
98
NGC 1365 30-inch McD
NGC 1365 de Vaucouleurs Atlas
Bright barred spiral!
99
Thank You!
Thanks also to William Brendan Parsons, Sue
French, Deirdre Kelleghan, Terry Moseley, Bob
Argyle, and Laura Hynes for answering various
questions I had about Birr Castle and the
Leviathan replica. Thanks also to Sir Patrick
Moore for his great little 1971 book, The
Astronomy of Birr Castle, and to Michael Tubridy
for his excellent pamphlet on the reconstruction.