The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono Oʼodham Nation, 88 kilometers (55 mi) west-southwest of Tucson, Arizona. With more than twenty optical and two radio telescopes, it is one of the largest gatherings of astronomical instruments in the Earth's northern hemisphere.
A quasar is an extremely luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object, abbreviated QSO. The emission from an AGN is powered by a supermassive black hole with a mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc. Gas in the disc falling towards the black hole heats up and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosities thousands of times greater than that of a galaxy such as the Milky Way. Quasars are usually categorized as a subclass of the more general category of AGN. The redshifts of quasars are of cosmological origin.
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation. The opposite change, a decrease in wavelength and increase in frequency and energy, is known as a blueshift, or negative redshift. The terms derive from the colours red and blue which form the extremes of the visible light spectrum. The main causes of electromagnetic redshift in astronomy and cosmology are the relative motions of radiation sources, which give rise to the relativistic Doppler effect, and gravitational potentials, which gravitationally redshift escaping radiation. All sufficiently distant light sources show cosmological redshift corresponding to recession speeds proportional to their distances from Earth, a fact known as Hubble's law that implies the universe is expanding.
The National Optical Astronomy Observatory (NOAO) was the United States national observatory for ground-based nighttime ultraviolet-optical-infrared (OUVIR) astronomy. The National Science Foundation (NSF) funded NOAO to provide forefront astronomical research facilities for US astronomers. Professional astronomers from any country in the world could apply to use the telescopes operated by NOAO under the NSF's "open skies" policy.
Halton Christian "Chip" Arp was an American astronomer. He is remembered for his 1966 book Atlas of Peculiar Galaxies, which catalogued unusual looking galaxies and presented their images.
The Australian Astronomical Observatory (AAO), formerly the Anglo-Australian Observatory, was an optical and near-infrared astronomy observatory with its headquarters in North Ryde in suburban Sydney, Australia. Originally funded jointly by the United Kingdom and Australian governments, it was managed wholly by Australia's Department of Industry, Innovation, Science, Research and Tertiary Education. The AAO operated the 3.9-metre Anglo-Australian Telescope (AAT) and 1.2-metre UK Schmidt Telescope (UKST) at Siding Spring Observatory, located near the town of Coonabarabran, Australia.
The Sloan Digital Sky Survey or SDSS is a major multi-spectral imaging and spectroscopic redshift survey using a dedicated 2.5-m wide-angle optical telescope at Apache Point Observatory in New Mexico, United States. The project began in 2000 and was named after the Alfred P. Sloan Foundation, which contributed significant funding.
In astronomy, a redshift survey is a survey of a section of the sky to measure the redshift of astronomical objects: usually galaxies, but sometimes other objects such as galaxy clusters or quasars. Using Hubble's law, the redshift can be used to estimate the distance of an object from Earth. By combining redshift with angular position data, a redshift survey maps the 3D distribution of matter within a field of the sky. These observations are used to measure detailed statistical properties of the large-scale structure of the universe. In conjunction with observations of early structure in the cosmic microwave background, these results can place strong constraints on cosmological parameters such as the average matter density and the Hubble constant.
In astronomy, the 2dF Galaxy Redshift Survey, 2dF or 2dFGRS is a redshift survey conducted by the Australian Astronomical Observatory (AAO) with the 3.9m Anglo-Australian Telescope between 1997 and 11 April 2002. The data from this survey were made public on 30 June 2003. The survey determined the large-scale structure in two large slices of the Universe to a depth of around 2.5 billion light years. It was the world's largest redshift survey between 1998 and 2003. Matthew Colless, Richard Ellis, Steve Maddox and John Peacock were in charge of the project. Team members Shaun Cole and John Peacock were awarded a share of the 2014 Shaw Prize in astronomy for results from the 2dFGRS.
An astronomical survey is a general map or image of a region of the sky that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of images, spectra, or other observations of objects that share a common type or feature. Surveys are often restricted to one band of the electromagnetic spectrum due to instrumental limitations, although multiwavelength surveys can be made by using multiple detectors, each sensitive to a different bandwidth.
The Joint Dark Energy Mission (JDEM) was an Einstein probe that planned to focus on investigating dark energy. JDEM was a partnership between NASA and the U.S. Department of Energy (DOE).
The Víctor M. Blanco Telescope, also known as the Blanco 4m, is a 4-metre aperture telescope located at the Cerro Tololo Inter-American Observatory, Chile on the summit of Mt. Cerro Tololo. Commissioned in 1974 and completed in 1976, the telescope is identical to the Mayall 4m telescope located on Kitt Peak. In 1995 it was dedicated and named in honour of Puerto Rican astronomer Víctor Manuel Blanco. It was the largest optical telescope in the Southern hemisphere from 1976 until 1998, when the first 8-metre telescope of the ESO Very Large Telescope opened.
The Nicholas U. Mayall Telescope, also known as the Mayall 4-meter Telescope, is a four-meter reflector telescope located at the Kitt Peak National Observatory in Arizona and named after Nicholas U. Mayall. It saw first light on February 27, 1973, and was the second-largest telescope in the world at that time. Initial observers included David Crawford, Nicholas Mayall, and Arthur Hoag. It was dedicated on June 20, 1973 after Mayall's retirement as director. The mirror has an f/2.7 hyperboloidal shape. It is made from a two-foot thick fused quartz disk that is supported in an advanced-design mirror cell. The prime focus has a field of view six times larger than that of the Hale reflector. It is host to the Dark Energy Spectroscopic Instrument. The identical Víctor M. Blanco Telescope was later built at Cerro Tololo Inter-American Observatory, in Chile.
Euclid is a wide-angle space telescope with a 600-megapixel camera to record visible light, a near-infrared spectrometer, and photometer, to determine the redshift of detected galaxies. It was developed by the European Space Agency (ESA) and the Euclid Consortium and was launched on 1 July 2023 from Cape Canaveral in Florida.
Michael Logan Lampton was an American astronaut, scientist, and founder of the optical ray tracing company Stellar Software. He was also known for his paper on electroacoustics with Susan M Lea, The theory of maximally flat loudspeaker systems.
Constance "Connie" Mary Rockosi is a professor and former department chair in the Astronomy and Astrophysics Department at the University of California, Santa Cruz. She earned her PhD in 2001 and helped design the camera for the telescope that was used as part of the initial Sloan Digital Sky Survey (SDSS). She also was in charge of the SDSS-III domain for the Sloan Extension for Galactic Understanding and Exploration (SEGUE) project and is the primary investigator on SEGUE-2. Her focuses involve the study of the Milky Way galaxy, with a focus on the evolution that it took to reach its current state.
The WiggleZ Dark Energy Survey is a large-scale astronomical redshift survey that was carried out on the 3.9 metre Anglo-Australian Telescope (AAT) at the Siding Spring Observatory, New South Wales between August 2006 and January 2011. The name stems from the measurement of baryon acoustic oscillations in the distribution of galaxies.
David James Schlegel is a Senior Scientist at the Lawrence Berkeley National Laboratory. He earned his Ph.D. in 1995 from the University of California, Berkeley. His earliest research was with Prof. Marc Davis and Douglas Finkbeiner working on dust maps of the universe. This research resulted in one of the most highly cited articles in astronomy. These maps proved to be essential for removing foregrounds in subsequent imaging or cosmic microwave background surveys.
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