General Information

Serial #

N/A

Part Number

1

Total Parts

6

AKA

N/A

Patents

N/A

General Description

Metal body and parts/ Synthetic cord and wire coverings, parts/ Glass parts

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

101.0 cm

Width

72.0 cm

Height

50.0 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Astronomy

Category

Observation equipment

Sub-Category

N/A

Manufacturer

AKA

Unknown

Country

Canada

State/Province

Ontario

City

Richmond Hill

Context

Country

Canada

State/Province

Ontario

Period

Unknown

Canada

An instrument used at the David Dunlap Observatory at the University of Toronto, one of Canada's most important astronomical observatories. The David Dunlap Observatory opened in 1935 as the result of a bequest from the wife of David Dunlap. The telescope was a 74 inch (188 cm) reflector built by Grubb Parsons of Newcastle-upon-Tyne in England. The 74 inch was then the largest telescope in Canada (surpassing the 72 inch telescope of the Dominion Astrophysical Observatory in Victoria) and became the second largest in the world after the 100 inch Hooker Telescope of the Mt. Wilson Observatory outside Los Angeles. DDO's reputation grew and following WWII, it began to graduate most of the astronomers produced in Canada with University of Western Ontario far behind. Beginning in the 1960s a number of other astronomy departments were created but UofT/DDO held its place, a position it probably still holds. The DDO had a good technical staff which gave them an advantage and, with most of the 1940s to early 1970s top astronomers coming from UofT, grants from NRC and then ENSERC were almost guaranteed and allowed UofT's top astronomers -- Hogg, van den Berg, Fernie, Bolton, Kamper, Martin, etc. to acquire or build some of the best equipment available in university observatories. For optical observatories, only the DAO had technical staff and budgets that surpassed those of DDO. In 2007, citing increasing light pollution, the University of Toronto announced plans to sell the Observatory property. In June 2008, it was sold to Corsica Development Inc., a subsidiary of Metrus Development Inc. and the Observatory was closed. In 2009 the Observatory buildings and 80% of the site were designated a cultural heritage landscape. Also in 2009 Corsica and the Royal Astronomical Society of Canada, Toronto Centre announced an agreement allowing the RASC to provide public education and outreach programs at the observatory, and to operate the 188 cm telescope.

Function

An astronomical instrument used to took images of stellar spectra.

Technical

Designed by Dr. John Lester, this was used mounted on the side of the 74" and took images of stellar spectra using a CCD detector (now defunct but in the instrument). Generally, an echelle spectrograph is a spectrograph that uses an échelle grating to achieve high spectral resolution and wide wavelength coverage. The overlapping spectra produced by the grating are separated by a prism or a grism before reaching the detector. The sensitivity brought to modern échelle spectrographs by CCD detectors has made them indispensable in such fields as astroseismology and extrasolar planet searches (Ref. 3).

Area Notes

Unknown

Details

Markings

Black and silver label on photomultiplier tube housing reads 'Photomultiplier Tube Housing/ PRODUCTS FOR RESEARCH, INC./ MADE IN U.S.A.'/ Black and silver label inside photomultiplier tube housing reads 'PHOTOMULTIPLIER TUBE SOCKET/ PRODUCTS FOR RESEARCH, INC./ DANVERS MASS./ Made in U.S.A./ 9658-81/ 6410-80/ RF TSA/ CATHODE ANODE'

Missing

Unknown

Finish

Flat black painted body/ Textured blue painted CCD detector casing/ Metallic grey photomultiplier tube housing/ Black and grey synthetic cord and wire coverings/ Black painted metal bars/ Colourless transparent glass/ Metallic parts

Decoration

N/A