The dome, constructed in 1881, originally housed a 12-inch Clark
refractor. The two foot wide dome slit was widened to accomodate
the 1-m Nickel reflector. The new slit is not overly generous
for the Nickel, with only a few inches of clearance on each side
when the telescope is centered. Also, the slit does block part
of the aperture (maximum occultation of about 40%) when the
telescope is at zenith distances less than 6.9 degrees. During
regular operations the dome is slaved to the telescope to ensure
that the telescope aperture is not blocked. Dome tracking of the
telescope is enabled with the DomeAuto setting in the POCO
telescope control software. It is also possible to manually
position the dome via the POCO software (select DomeHold and use
the Manual Dome function) or via a manual rocker switch in the
Nickel dome (you must select DomeFloor in POCO to position the
dome using the rocker switch). The dome shutter can be opened or
closed remotely via the naux_fe software or manually from a
control box moun