A segmented-mirror reflector at an altitude of 2025 m on Mount Fowlkes, Texas, opened in 1997. It is part of McDonald Observatory, and is jointly owned by the University of Texas, Pennsylvania State University, the Ludwig Maximilian University in Munich, and the Georg-August University in Göttingen. Its mirror consists of 91 hexagonal segments each 1 m wide, forming an 11.1 × 9.8 m hexagon; however, its usable aperture is equivalent to a single mirror of 10 m. The telescope is designed primarily for spectroscopy rather than imaging. It is permanently angled at 55° altitude, but rotates freely in azimuth. The telescope remains stationary during observations; a movable secondary tracks objects as the Earth rotates. It is named after William P. Hobby and Robert E. Eberly, supporters of public education in Texas and Pennsylvania respectively.
http://www.as.utexas.edu/mcdonald/het/het.html Official telescope website.https://mcdonaldobservatory.org/news/gallery/het-dome-dusk
https://mcdonaldobservatory.org/news/gallery/het-mirror-through-dome
- noiseless coding
- noise margin
- noise sequence
- noise source
- noise temperature
- noisy mode
- Nok culture
- Nollet, Abbé Jean Antoine
- no-load
- nomad((in cytology))
- nomadism
- Nomarski microscope
- nomenklatura
- Nomex cloth
- nomic
- composite hypothesis
- composite idea
- Composite Infrared Spectrometer
- composite intrusion
- composite material
- composite polymer
- composite-spectrum binary
- composite-stratotype
- composite volcano
- composition