|Location||Kitt Peak, Arizona, USA|
|Diameter||Blank diameter: 3.51155 m (138.25") / Diameter to bevels: 3.49885 m (137.75")|
|Focal length||f/ 1.75|
|Dome||Truncated Rhombi-cube octahedron|
The WIYN Observatory is owned and operated by the WIYN Consortium. Its telescope, a 3.5-meter instrument, is the newest and second largest telescope at Kitt Peak National Observatory in Arizona. Most of the capital costs for the observatory were provided by the University of Wisconsin–Madison, Indiana University, and Yale University, while the National Optical Astronomy Observatory provides most of the operating services.
Standard and Future Instrumentation
HYDRA: HYDRA is a multiobject spectrograph using fiber optics positioned in the focal plane to allow up to 100 separate objects to be observed at a time. The light is guided to a spectrograph room under the main telescope where a CCD camera records the spectrum of each object. The field of view is ~1 degree. 
MiniMo: MiniMo is a CCD consisting of two 2048 x 4096 pixel chips, with a field of view of 9.6 arcminutes. The two separate chips allows for faster readout of the image than would have been otherwise possible, as they can be read out simultaneously. 
WHIRC: WHIRC is a near infrared high resolution imaging camera commissioned in 2008. WHIRC was a joint project between the WIYN partners and STScI. It consists of a 2k x 2k detector providing an excellent pixel scale of 0.1"/pixel and a field of view of 200 x 200 arcsec. WHIRC can be used with the WIYN Tip/Tilt Module (WTTM) to provide exquisite high-resolution images. A large set of filters is available.
ODI: The One Degree Imager (ODI) is the flagship of WIYN's new instrument initiatives. ODI will utilize both WIYN's one degree field of view and excellent image quality. The focal plane of the optical imager will be sampled with 0.1" pixels, or 1 Gigapixels in total. Image sharpness will be actively improved by correcting images for tip/tilt motion during the integration. Corrections will be done over the entire field of view using a novel detector technology called Orthogonal Transfer Array CCD, making ODI a unique and competitive instrument in the era of wide-field surveys. ODI is funded by the WIYN partners and the National Science Foundation. It is expected that scientific programs will be undertaken with ODI starting in the second semester of 2010.
The WIYN Consortium is governed by the Board of Directors, which includes three members of each partner institution. The Board meets twice a year. The Science Steering Committee provides scientific guidance to the Board and the WIYN Director.
Between 2000-2008, the WIYN Director was Dr. George Jacoby, followed by Dr. Pierre Martin (2008-2010). Since December 2010, Dr. Pat Knezek serves as interim director. Since 2013, Dr. Eric Hooper (UW Madison) serves as interim director.
Both Yale University and NOAO have announced their withdrawal from the WIYN consortium as of April 1st 2014 and February 1st 2015, respectively. Missouri University will become an operational partner of WIYN as of fall 2014.