Lick Obs. Mt Hamilton 4,200ft 994.61 Kb	Shane 3m observatory 126.25 Kb	Hosts: Remington Stone (Lick Obs.), Chung-Pei Ma & James Graham (U.C.Berkeley) 1119.81 Kb
PRS and hosts at original safe door 1185.43 Kb	3m Shane reflector with AO(*) laser 136.84 Kb	AO(*) laser 157.37 Kb
Shane 3m with laser 457.99 Kb	Shane secondary 397.09 Kb	Shane primary mirror cell 437.21 Kb
Shane Adaptive Optics (AO) package(*) 489.76 Kb	Shane laser, detail 508.83 Kb	Adaptive optics 1157.57 Kb
In Nickel dome 1113.84 Kb	Instruments on 1m Nickel reflector 1135.36 Kb	Nickel at rest 1161.55 Kb
36in Crossley reflector 1163.55 Kb	Crossley aperture 1101.48 Kb	Dinner at Lick before observing 1153.08 Kb
36in Lick refractor 151.03 Kb	36in Lick refractor 2 145.17 Kb	Rem Stone at refractor 1120.89 Kb
PRS at refractor 1131.15 Kb	Business end 1138.31 Kb	Refractor wheels 152.23 Kb
Moon eyepiece in foreground 1167.48 Kb	Rem levitating an eyepiece 1104.60 Kb	36in trained on the Moon 170.92 Kb
PRS at the moon eyepiece 568.22 Kb	James Lick tomb 192.88 Kb	AO(*) laser firing 156.91 Kb
Pierre and Vlad at Nickel 40in. June 1, 2005 202.7 Kb	Rem Stone filling Dewar on Nickel 40in. 115.5 Kb	Vlad and Rem filling Dewar 201.8 Kb

^(*)AO: Adaptive Optics Laser Guide Star:

The twinkling and dancing of starlight is due to the deformation of its wavefront as it travels down through the atmosphere to the eye, or the telescope. The AO system used at the Shane telescope projects an intense laser beam - along the telescope axis - where it excites the sodium atoms 90km up in the upper atmosphere. This produces an artificial star whose wavefront can be observed by the AO instrument at the telescope. That wavefront is analyzed to deduce the deformation produced by its travel down through the atmosphere - and that deformation is then applied, in reverse, to the starlight coming through the telescope. That light is bounced a small mirror which is pushed and pulled several times a second by a number of actuators driven by the AO logic so that the wavefront arrives at the final recording instrument as flat as possible.

This idea can be applied by using a normal guide star if there is one close to the object under study. But such a bright star is not always available in the given field of view. Hence the idea of creating an artificial guide star (using the laser) which is always available, close to the object under scrutiny.

(Since the laser is fairly intense, its use is governed by regulations of the US Space Command and the FAA - which, amongst other things, require that several warm-blooded lookouts be posted in the cold night outside the telescope at all times the laser is functioning so that the laser can be immediately turned off if a plane is observed approaching the laser vector. Perfect jobs for undergrads.)