Information: - Astronomy is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry, in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, moons, stars, galaxies, and comets; while the phenomena include supernovae explosions, gamma ray bursts, and cosmic microwave background radiation. More generally, all astronomical phenomena that originate outside Earth's atmosphere are within the purview of astronomy. A related but distinct subject, physical cosmology, is concerned with the study of the Universe as a whole. - The Maksutov (also called a "Mak") is a catadioptric telescope design that combines a spherical mirror with a weakly negative meniscus lens in a design that takes advantage of all the surfaces being nearly "spherically symmetrical". The negative lens is usually full diameter and placed at the entrance pupil of the telescope (commonly called a "corrector plate" or "meniscus corrector shell"). The design corrects the problems of off-axis aberrations such as coma found in reflecting telescopes while also correcting chromatic aberration. It was patented in 1941 by Russian optician Dmitri Dmitrievich Maksutov. Maksutov based his design on the idea behind the Schmidt camera of using the spherical errors of a negative lens to correct the opposite errors in a spherical primary mirror. The design is most commonly seen in a Cassegrain variation, with an integrated secondary, that can use all-spherical elements, thereby simplifying fabrication. Maksutov telescopes have been sold on the amateur market since the 1950s. - Amateur astronomy is a hobby whose participants enjoy watching the sky, and the abundance of objects found in it with the unaided eye, binoculars, or telescopes. Even though scientific research is not their main goal, many amateur astronomers make a contribution to astronomy by monitoring variable stars, tracking asteroids and discovering transient objects, such as comets and novae. - A reflecting telescope (also called a reflector) is an optical telescope which uses a single or combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter objectives. Almost all of the major telescopes used in astronomy research are reflectors. Reflecting telescopes come in many design variations and may employ extra optical elements to improve image quality or place the image in a mechanically advantageous position. Since reflecting telescopes use mirrors, the design is sometimes referred to as a "catoptric" telescope. - John F. Gregory ( 1927 -- November 14 , 2009 ) was an American optical engineer and a popularizer of amateur telescope making . He is credited with the design of a version of the Maksutov telescope called the '' Gregory - Maksutov telescope '' . - Amateur telescope making is the activity of building telescopes as a hobby, as opposed to being a paid professional. Amateur telescope makers (sometimes called ATMs) build their instruments for personal enjoyment of a technical challenge, as a way to obtain an inexpensive or personally customized telescope, or as a research tool in the field of astronomy. Amateur telescope makers are usually a sub-group in the field of amateur astronomy. What object entity has the relation of 'occupation' with the subject 'john f. gregory'? Choices: - major - optician - pupil - research - science
optician
Question: Information: - Golf is a club and ball sport in which players use various clubs to hit balls into a series of holes on a course in as few strokes as possible. - A tee is a stand used to support a stationary ball so that the player can strike it, particularly in golf, tee ball, American football, and rugby. - Troy is a city in Pike County, Alabama, United States. As of the 2010 census, the population was 18,033. Troy has experienced a growth spurt of over 4,000 people since 2000. The city is the county seat of Pike County. Troy is a college town and is home to Troy University. It formally incorporated on February 4, 1843. - Troy University is a comprehensive public university that is located in Troy, Alabama, United States. It was founded on February 26, 1887 as Troy State Normal School within the Alabama State University System by an Act of the Alabama Legislature. It is the flagship university of the Troy University System with its main campus enrollment of 6,998 students and the total enrollment of all Troy University campuses of 19,579. Troy University is regionally accredited by the Southern Association of Colleges and Schools Commission on Colleges (SACS) to award associate, baccalaureate, master's, education specialist, and doctoral degrees. - A golf course is the grounds where the game of golf is played. It comprises a series of holes, each consisting of a teeing ground, a fairway, the rough and other hazards, and a green with a flagstick ("pin") and hole ("cup"). A standard round of golf consists of 18 holes. Most courses contain 18 holes; some share fairways or greens, and a subset has nine holes, played twice per round. Par-3 courses consist of nine or 18 holes all of which have a par of three strokes. - Trojan Oaks Golf Course was a 9 - hole championship golf course on the campus of Troy University . It is for use by the general public , golf team , and students . Students are given a discount on Tuesday and Wednesday to encourage teenage and young adult participation in the sport . The Trojan Oaks is 3,211 yards ( 2,936 m ) from the longest tee . The par for the course is 36 with a course rating of 35.5 and a slope rating of 125 . The greens and fairways are both Bermuda grass . The course was built over the course of two years and opened in 1977 under the supervision of Chancellor Ralph Wyatt Adams . The course was closed in March 2010 in order to build a new basketball arena on the grounds . It will not reopen . The course does not attract a great deal of extra-county players , other than faculty and friends of the university . This is in part due to the presence of a course on the world - renowned Robert Trent Jones Golf Trail in nearby Montgomery . The course also serves as the practice facility for the Troy University men 's and women 's golf teams . - A public university is a university that is predominantly funded by public means through a national or subnational government, as opposed to private universities. Whether a national university is considered public varies from one country (or region) to another, largely depending on the specific education landscape. - The teeing ground is the area where play begins in a hole of golf. The terms tee, tee box, and "teeing ground" are synonymous. The name derives from the tee used to elevate a golf ball before striking it to commence play. What object entity has the relation of 'located in the administrative territorial entity' with the subject 'trojan oaks golf course'? Choices: - alabama - hole - most - of - rugby - troy - university
Answer:
alabama