Aldershot observatory is a circular red-brick building with a domed roof standing on Queens Avenue in Aldershot Military Town near Aldershot, England, home to the British Army since circa 1854. Inside is an 8-inch (200 mm) refracting telescope on a German-type equatorial mount with a clockwork drive which will run for about 2 hours without rewinding, this has a facility to vary the drive rate.
The telescope and observatory building were a gift from aviation pioneer Patrick Young Alexander to the British Army, a fact which is recorded by a plaque near the observatory door. It reads: ‘Presented to the Aldershot Army Corps by Patrick Y Alexander Esq 1906’.
Design And Construction :
The building is of conventional design. It is principally of redbrick with some white stone masonry, surmounted by a cupola. There are three steps leading up to a heavy ornamental door. The dome was originally covered in a rubberoid material (modified bitumen) but in time this perished and the dome was rebuilt with copper cladding. The building today is generally in good condition.
In the best traditions of Victorian engineering, the dome rotation is controlled by a pulley and rope loop, as is the dome opening mechanism. The dome opening is triangular in shape, a design which limits the usefulness of the telescope because the area of sky visible reduces sharply as the telescope is pointed to the zenith.
Early photographs show the telescope to have been light green in colour. It is now painted a dark British army green. Major maintenance took place in 1987, this resulted in the copper dome and the instrument being repainted drab green, the original colour was a light blue/green used by the military on all instruments of the time (1940's) it should be noted that in November 2006 the electricity supply was disconnected, as a savings measure.
Just what use the British Army made of their new telescope is a bit of a mystery. It was, apparently, used in the training of officers in astronavigation. The telescope may also have been employed in monitoring experimental flights from HM Balloon Factory established at nearby Farnborough in 1908 (later to become the Royal Aircraft Establishment). Over the last 100 years, many local amateur and professional astronomers have made use of the telescope.
Since the end of the Second World War, use of the observatory has continued on an ad hoc basis. The army permitted the telescope to be used by interested amateurs provided only that they could demonstrate competence with the instrument; they were allowed to draw a key from a nearby guardroom and use the telescope as they wished. A story now often repeated, is the recollection of a user who remembers that military regulations imposed at one time gave some difficulty: the key would be issued only between the hours of 9am and 5pm — the observatory had to be securely locked by 5:30 and the key returned!
In 1979 the observatory was closed because of corrosion of the dome and defects in the dome traverse gear. Trees were allowed to grow up around the building and the observatory was neglected. At some point the observatory was broken into by thieves who stole the sighting telescope, a modern replacement has since been installed.
In 1998 the observatory was rediscovered by a local amateur astronomer. Work started on cleaning the interior which was by then covered in dust, dirt and leaves. The telescope itself was in working condition, in 1999 the Army gave permission for the removal of the lens cell to be removed for refurbishment. By April 2000, the lens cell was replaced and the telescope fully restored and the larger of the surrounding trees had been removed. On 6 May 2000, the Aldershot Observatory was opened to the public for the first ever, the event stimulated considerable public interest in its future.