The University of Chicago

373 W. Geneva St, Williams Bay WI 53191 (Latitude 42 34.2, Longitude -88 33.4)

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Research and Development at Yerkes Observatory.... then and now....
The primary research program using Yerkes telescopes in recent years has been the measurement of stellar motions by comparison of photographs taken decades apart with the 40-inch refractor, as well as other telescopes.  The high quality of the photos taken at Yerkes in the early 1900s has allowed these measurements to attain extremely high precision.  Prof. Kyle Cudworth and his collaborators have been concentrating on such measurements for star clusters containing the oldest stars in our Milky Way Galaxy.  The general goal is to increase our understanding of how the Galaxy formed and how it has changed since it formed.  The results from this Yerkes research is also contributing to the calibration of the multi-national Sloan Digital Sky Survey (SDSS), particularly its extension aimed at increasing our understanding of the Milky Way
moon craters 1 moon craters 2 Images of Moon craters scanned from a plate taken by George Ritchey on Nov. 20, 1901 with the 40-inch refractor telescope.
m5 ritchey 1900

The globular cluster M5 photographed by George Ritchey with the 40-inch refractor on May 28, 1900.  This 5-hour exposure was the first recorded stellar photo with the 40-inch.  The original plate, along with several others of this cluster, has been used in modern research measuring the motions of stars in this cluster.

m5 cudworth 1988

A photograph of the globular cluster M5 taken by Kyle Cudworth with the 40-inch refractor on April 8, 1988.  This 30-minute exposure approximately matches the 5-hour exposure taken in 1900, demonstrating the significant improvement in photographic emulsions over the decades.  The star images on this photo are very sharp compared with those on the 1900 image due to the steadiness of the earth’s atmosphere at the time of the 1988 observation.


The Yerkes Observatory Photographic Plates
Yerkes Observatory houses a collection of over 170,000 astronomical photographic plates almost all taken in the twentieth century. Roughly 45% are direct plates, 45% slit spectra and 10% solar images, spectra or spectroheliograms. The majority of the plates were taken using the observatory's 40-inch refractor (Hale 1897), the former 24-inch reflector (Ritchey 1901) and the wide-field photographic telescope (Barnard 1905). more...

hawc hawc hawc hawc
HAWC (High-resolution Airborne Widebandwidth Camera) is the facility Far-Infrared camera for SOFIA (Stratospheric Observatory For Infrared Astronomy). The camera is a project of the University of Chicago, in collaboration with Goddard Space Flight Center and Rochester Institute of Technology. HAWC will utilize a 12 x 32 array of bolometer detectors constructed using the ion-implanted silicon pop-up detector technology being developed at Goddard Space Flight Center. This new technology enables construction of close-packed, two-dimensional arrays of bolometers with high quantum efficiency and area filling factors of greater than 95%. The array will be cooled by an adiabatic demagnetization refrigerator and operated at a temperature of 0.2 K.
The instrument has been designed and built by engineers at Yerkes Observatory.

sdss 1 The Sloan Digital Sky Survey (SDSS) is the most ambitious astronomical survey ever undertaken. When completed, it will provide detailed optical images covering more than a quarter of the sky, and a 3-dimensional map of about a million galaxies and quasars. As the survey progresses, the data are released to the scientific community and the general public in annual increments. sdss 2

The ARC Echelle Spectrograph, ARCES, is a high-resolution echelle spectrograph designed as a facility instrument for the Apache Point Observatory (APO) 3.5m Telescope. (APO is owned and operated by the Astrophysical Research Consortium, ARC.) The spectrograph covers a wavelength range of 320-1000 nm in a single exposure. echelle camera echelle