Lantern slide 'Photoelectric photometer on 12-inch telescope (1925)'
Astronomy
Photography
Optical instruments
Measuring instruments
Photometry
Lantern slide of the photoelectric photometer around 1925. From the Observatory's lantern slide collection, marked "PE 2." Robert Baker continued Stebbin's photometry work when he arrived at Illinois in 1923. He continued to use the 12-inch refractor for photometer until about 1926 after which time he used the rebuilt 30-inch reflector.
Photographic Department, University of Illinois
Astronomy Department, University of Illinois, Urbana, Illinois
1925
lantern slide
English
still image
University of Illinois Observatory, Urbana, Illinois
Photograph 'Photoelectric photometer'
Astronomy
Photography
Photometry
Measuring instruments
Optical instruments
Photograph of the photoelectric cell photometer attached to the 12-inch refractor. The photograph dates to about 1913-1915. During the summer of 1915, Dr. Stebbins took this photometer to Lick Observatory to study the variable star Beta Lyrae. Photographs of that photometer on the Lick 12-inch telescope match this photograph of the photometer on the Illinois 12-inch telescope.
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1915
still image
English
still image
University of Illinois Observatory, Urbana, Illinois
Lantern slide 'Potassium Photoelectric cell'
Astronomy
Photography
Electrical apparatus
Measuring instrument
Optical instrument
Lantern slide of a photoelectric cell made by Jacob Kunz. Part of the Observatory's lantern slide collection, marked "PE 5."
Photographic Department, University of Illinois
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1925
lantern slide
English
still image
University of Illinois Observatory, Urbana, Illinois
Lantern slide '30-inch Reflecting telescope'
Astronomy
Photography
Optical instrument
Telescope
Architecture
Lantern slide of the 30-inch reflecting telescope after it was rebuilt between 1925-1927. The dual-channel photoelectric photometer hangs on the end of the telescope. The rebuilt telescope was located in a 15-foot domed Observatory located on Florida Avenue south of Mount Hope Cemetery. The telescope was rebuilt by the local firm of J.B. Hayes for $1560 starting in January 1925. Baker announced its completion at the American Physical Society's annual meeting on December 29, 1927. This lantern slide is part of the Observatory's collection and is marked "PE 9."
Baker, Robert H. "The 30-inch Reflecting Telescope and Photoelectric Photometer of the University of Illinois." Popular Astronomy. 122:86-91.
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1925
still image
English
University of Illinois Observatory, Urbana, Illinois
Lantern slide "U of I Eclipse station 1918, Rock Springs, Wyoming"
Astronomy
Photography
Solar Eclipse
Measuring instrument
Photometry
One of over 1000 lantern slides in the Observatory's collection. Labelled "E1" this is a photograph of the photoelectric photometer Dr. Joel Stebbins and Dr. Jakob Kunz used to observe the solar eclipse on June 8, 1918. The photograph also appeared in the article "The Illinois eclipse expedition to Rock Springs, Wyoming" in Popular Astronomy, Vol. 26, p.665 as figure 2 on page 668.
Photographic Department, University of Illinois
Kunz, J. and J. Stebbins (December 1918) "The Illinois eclipse expedition to Rock Springs, Wyoming" Popular Astronomy, Vol. 26, p.665-676.
Astronomy Department, University of Illinois, Urbana, Illinois
1918
Michael Svec
still image
English
University of Illinois Observatory, Urbana, Illinois
Galvanometer room
Astronomy
Photography
Electrical apparatus
Measuring instrument
Photometry
Figure 2: Galvanometer and accessories for the selenium photometer. Page 191.
Visible in the photograph are the galvanometer, reading telescope, scale, batteries,Wheatstone bridge, and resistance boxes. Was located in the west-central transit room.
Astrophysical Journal
Stebbins, Joel. (1910). The measurement of the light of stars with a selenium photometer, with an application to the variations of Algol. 32, 185-214
http://articles.adsabs.harvard.edu//full/1910ApJ....32..185S/
1910
photograph from journal
English
document
University of Illinois Observatory, Urbana, Illinois
Selenium cell photometer
Astronomy
Photography
Measuring instrument
Electrical apparatus
Photometry
Figure 1: Selenium cell in ice-pack attached to 12-inch refractor. Page 190.
Astrophysical Journal
Stebbins, Joel. (1910) The measurement of the light of stars with a selenium photometer, with an application to the variations of Algol. 32, 185-214.
http://adsabs.harvard.edu/abs/1910ApJ....32..185S
1910
Image from journal
document
University of Illinois Observatory, Urbana, Illinois
Photoelectric photometer filters
Astronomy
Optical instrument
Photometry
Wood, metal, glass
Small wooden box (4 ¾ x 2 ¾ x 2”), 11 shades, some marked .66, .86, 1.31, 1.56, 1.80, 2.95, 4 unlabeled. Possibly 1917.
Made reference to use of shades in several papers including Nova Aquilae and Algol (1921).
Unknown
Astronomy Department, University of Illinois, Urbana, Illinois
circa 1917
Michael Svec
Copyright Michael Svec
image/jpg
English
physical object
University of Illinois Observatory Collection A210
University of Illinois Observatory, Urbana, Illinois
Visual polarizing photometer
Astronomy
Measuring instrument
Optical instrument
Photometer
Wood, brass, glass
Wooden box with hinged lid, barlow adapter, brass ring. Box measures 30” x 9” x 9”. The photometer is 24” long.
The visual photometer utilizes the polarizing properties of doubly-refracting crystals to measure stellar magnitudes. It is used on double stars where one of the stars has a known magnitude.
“The polarizing photometer used in these observations was constructed by Alvan Clark & Sons. It is of the form devised by Professor Pickering and described by him in Annals of Harvard College Observatory, Vol.11, page 4, where it is designated as ‘Photometer H’. A Wollaston prism forms two images of each star, and these images are varied in intensity by rotating a Nichol placed between the eye and the eyepiece. . . This instrument is capable of extremely accurate results, bit its use is limited to those stars which are closer than about 100”"
Used by Stebbins to observe double stars in 1904-06 and Delta Cephei in 1907 leading to pioneering work by on measuring brightness using electricity making visual photometry obsolete. After Stebbins left in 1922 with the photoelectric photometer, C.C. Wylie resumed using the visual photometer to study WW Aurigae and Delta Cephei. It was used in the 1950s and early 1960s for instruction after a cleaning by J.W. Fecker in 1954. In 1957 Robert Tull and in 1961 Robert Roeder prepared instructions on the photometer’s use.
Alvan Clark & Sons
Stebbins, J. (1907, July) Photometric observations of Double stars. The University Studies, vol, 2, no. 5. University of Illinois Press.
Stebbins, J. (1908). The light-curve of δ Cephei. Astrophysical Journal, 27, 188-193.
Wylie, C.C. (1925). Note on the eclipsing variable WW Aurigae. Popular Astronomy, 33:600-601.
Report of observatories. (1924). University of Illinois Observatory. Popular Astronomy. 32:98-99.
Astronomy Department, University of Illinois, Urbana, Illinois
1899
Michael Svec
copyrighted by Michael Svec.
image/jpg
English
physical object
University of Illinois Observatory Collection A131
University ID 016670, obs 66
University of Illinois Observatory, Urbana, Illinois