INSTRUMENT_HOST_DESC 
Instrument Host Overview
========================
The 'LOWELL' instrument host is used when it is not possible to
determine which of the various available telescopes at Lowell
Observatory were used in making the observations associated with
a data set.
The following table gives the specifications of the various Lowell
Observatory telescopes.
Perkins Hall 42in Hall 42in
72in F/16 F/8 31in 21in
========= ========= ========= ========= ==========
Longitude 111d 32' 111d 32' 111d 32' 111d 32' 111d 39'
09.3in 07.9in 07.9in 09.0in 59.2in
Latitude +35d 05' +35d 05' +35d 05' +35d 05' +35d 12'
48.6in 48.3in 48.3in 54.6in 10.4in
Altitude 7236ft. 7236ft. 7236ft. 7243ft. 7260ft.
(2206m) (2206m) (2206m) (2208m) (2213m)
Dp 72in(1.8m)42in(1.1m) 42in(1.1m) 31/29.5in 20.78
(0.79/0.75m) (0.53m)
F/# 17.5 16.0 8.0 15.7 15.9
EFI 1256.5in 669in 334in 464in 332.5in
(31.93cm) (16.99cm) (8.48cm) (11.78cm) (8.44cm)
Scale
(in/mm) 6.45 12.1 24.3 17.5 24.3
BFI 51.5in 25in 25in 25in 20in
(1.30cm) (0.63cm) (0.63cm) (0.63cm) (0.51cm)
Fp/# 4.18 4.0 4.0 5.0 3.4
FLp 300.6in 168in 168in 155in 70.0in
(7.635cm) (4.267cm) (4.267cm) (3.94cm) (1.77cm)
Dsa 16.3in 9.7in 16.2in 9.0in 4.6in
(0.41m) (0.25m) (0.41m) (0.22m) (0.12m)
Is 284.1in 154.3in 128.4in 134.9in 72.7in
(7.22m) (3.92m) (3.26m) (3.43m) (1.85m)
Os 68.0in 38.7in 64.6in 45.1in 15.3in
(1.72m) (0.98m) (1.64m) (1.14cm) (0.39m)
Ms 232.6in 129.3in 103.4in 109.9in 54.7in
(5.91m) (3.28m) (2.63m) (2.79m) (1.39m)
mag 4.2 4.0 2.0 3.0 4.7
K1 1.0 2.32 2.32 1.00 1.00
K2 3.65 5.96 16.84 5.01 3.35
Notes:
1) Longitude and latitude are good to about +/ 0.2.
2) The altitudes are good to about +/ 1 meter.
3) The Hall F/16 is not a true Cassegrain telescope since the primary
is a hyperboloid.
4) The Hall F/8 is a RitcheyChretien telescope.
5) The 31 inch primary is F/5. However, it is stopped down to 29.5
inches.
6) Only the Hall F/8 has a known optimum back focal distance.
7) The conic constant is defined such that 0 is a circle and 1 is a
parabola.
8) DSA is the diameter of the axial cone at the secondary. The diameter
of the secondary is 1 to 2 inches larger than DSA.
Lowell Observatory currently maintains an informational World Wide Web
site at http://www.lowell.edu/.
