The Yale University Observatory, also known as the Leitner Family Observatory and Planetarium, is an

astronomical Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxi ...

observatory An observatory is a location used for observing terrestrial, marine, or celestial events. Astronomy, climatology/meteorology, geophysical, oceanography and volcanology are examples of disciplines for which observatories have been constructed. ...

owned and operated by

Yale University Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the w ...

, and maintained for student use. It is located in Farnham Memorial Gardens near the corner of Edwards and Prospect Streets,

New Haven New Haven is a city in the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound in New Haven County, Connecticut and is part of the New York City metropolitan area. With a population of 134,023 ...

Connecticut Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the ...

. In the 21st century, the Yale Student Observatory, the Leitner observatory also has public outreaches and supports astronomy for students of the college. However, the Yale Observatory traces its history back to being one of the first formal institutions for astronomical observation in the United States, dating to the 1830s.

History

In 1828 Sheldon Clark donated 1200 US dollars to Yale to procure a Dollond refracting telescope. Yale's first

, the Atheneum, was founded in 1830, situated in a tower. From 1830 it housed Yale's first refractor, a Dollond donated by Sheldon Clark. It was the largest in the United States at the time. With this telescope

Olmsted Olmsted may refer to: People * Olmsted (name) Places * Olmsted Air Force Base, inactive since 1969 * Olmsted, Illinois * Olmsted County, Minnesota * Olmsted Falls, Ohio * Olmsted Point, a viewing area in Yosemite National Park * Olmsted Townsh ...

and

Elias Loomis Elias Loomis (August 7, 1811 – August 15, 1889) was an American mathematician. He served as a professor of mathematics and natural philosophy at Western Reserve College (now Case Western Reserve University), the University of the City of New Yo ...

made the first American sighting of the return of

Halley's Comet Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the on ...

on 31 August 1835. (It had been seen in Europe on 6 August, but no news of this had reached the United States.) The telescope was mounted on casters and moved from window to window, but it could not reach altitudes much over 30 deg above the

horizon The horizon is the apparent line that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body. This line divides all viewing directions based on whether i ...

. In 1870, a cylindrical turret was added above the tower, so that all altitudes could be reached. In the same year a 9-inch Alvan Clark refractor was mounted in the observatory. The building was demolished in 1893 and the telescope is now at the

Smithsonian Institution The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Found ...

in Washington, D.C. The observatory, in the turret (modelled after the gun turret of the ironclad ship

USS Monitor USS ''Monitor'' was an ironclad warship built for the Union Navy during the American Civil War and completed in early 1862, the first such ship commissioned by the Navy. ''Monitor'' played a central role in the Battle of Hampton Roads on 9 Ma ...

), housed a

Alvan Clark Alvan Clark (March 8, 1804 – August 19, 1887), born in Ashfield, Massachusetts, the descendant of a Cape Cod whaling family of English ancestry, was an American astronomer and telescope maker. Biography He started as a portrait painter and engra ...

refractor donated by Joseph E. Sheffield. The telescope was later housed in the dome on Bingham Hall (the dome later converted to a small

planetarium A planetarium ( planetariums or ''planetaria'') is a Theater (structure), theatre built primarily for presenting educational entertainment, educational and entertaining shows about astronomy and the night sky, or for training in celestial navi ...

, and now used as an experimental

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

). An telescope financed by E.M. Reed of

was first used for photographing the Sun during the

Transit of Venus frameless, upright=0.5 A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and a superior planet, becoming visible against (and hence obscuring a small portion of) the solar disk. During a tr ...

on December 6, 1882. The observatory also possessed a heliometer, ordered from Repsold and Sons by H. A. Newton in 1880, delivered in time for measurements of the

on December 6, 1882 for determination of

solar parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby object ...

. This is the same type of instrument that Friedrich Bessel used in 1838 for the first significant determination of a

stellar parallax Stellar parallax is the apparent shift of position of any nearby star (or other object) against the background of distant objects, and a basis for determining (through trigonometry) the distance of the object. Created by the different orbital p ...

(of the star 61 Cygni). Under the direction of W. L. Elkin from 1883 to 1910 the heliometer yielded (according to Frank Schlesinger) the most (238) and the best parallaxes obtained before the advent of

photographic Photography is the art, application, and practice of creating durable images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed ...

astrometry Astrometry is a branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies. It provides the kinematics and physical origin of the Solar System and this galaxy, the Milky Way. Hist ...

. In the late 1890s, W. L. Elkin built two batteries of

cameras A camera is an optical instrument that can capture an image. Most cameras can capture 2D images, with some more advanced models being able to capture 3D images. At a basic level, most cameras consist of sealed boxes (the camera body), with a ...

equipped with rotating shutters for obtaining the velocities as well as the heights of meteors, pioneering work in the study of meteors.* The Loomis Tower on Canner Street, erected in 1923 in memory of Elias Loomis (1811–1889), was at the time the largest polar telescope in America. The installation was originally designed for the comfort of the observer who sat at the

eyepiece An eyepiece, or ocular lens, is a type of lens that is attached to a variety of optical devices such as telescopes and microscopes. It is named because it is usually the lens that is closest to the eye when someone looks through the device. The ...

in a warm room at the top of the tower. The tube (beneath the stairs) was parallel to the polar axis of the

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's sur ...

. The building at the base of the tower had a sliding roof and housed a

optical flat An optical flat is an optical-grade piece of glass lapped and polished to be extremely flat on one or both sides, usually within a few tens of nanometres (billionths of a metre). They are used with a monochromatic light to determine the flatn ...

coelostat A solar telescope is a special purpose telescope used to observe the Sun. Solar telescopes usually detect light with wavelengths in, or not far outside, the visible spectrum. Obsolete names for Sun telescopes include heliograph and photoheliograp ...

mirror A mirror or looking glass is an object that reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the direction of the im ...

driven equatorially and reflecting light from any unobscured part of the sky through both a

and a

visual The visual system comprises the sensory organ (the eye) and parts of the central nervous system (the retina containing photoreceptor cells, the optic nerve, the optic tract and the visual cortex) which gives organisms the sense of sight ...

guide A guide is a person who leads travelers, sportspeople, or tourists through unknown or unfamiliar locations. The term can also be applied to a person who leads others to more abstract goals such as knowledge or wisdom. Travel and recreation Ex ...

telescope, both of the same

focal length The focal length of an optical system is a measure of how strongly the system converges or diverges light; it is the inverse of the system's optical power. A positive focal length indicates that a system converges light, while a negative foc ...

, 600 inches. In 1945, the telescope was reversed, with the objective at the top, the plate holder at the foot of the tube. The telescope was thus rigidly mounted for photographing the polar region only, for the purpose of investigating the wobbling of the axis of rotation of the earth and redetermining the constants of

precession Precession is a change in the orientation of the rotational axis of a rotating body. In an appropriate reference frame it can be defined as a change in the first Euler angle, whereas the third Euler angle defines the rotation itself. In oth ...

and

nutation Nutation () is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behaviour of a mechanism. In an appropriate reference frame ...

. The Loomis Telescope was moved to

Bethany, Connecticut Bethany is a town in New Haven County, Connecticut, United States. The population was 5,297 at the 2020 census. History Bethany was first settled in 1717, but it was not until May 1832 that Bethany separated from Woodbridge to become incorporate ...

in 1957, to continue monitoring the apparent motion of the axis of the earth. Carol Williams analyzed plates for her Ph.D. thesis, 1967. She found apparent motions largely correlated with tidal disturbances of the

earth's crust Earth's crust is Earth's thin outer shell of rock, referring to less than 1% of Earth's radius and volume. It is the top component of the lithosphere, a division of Earth's layers that includes the crust and the upper part of the mantle. The ...

. The observatory was renamed as the Leitner Family Observatory and Planetarium in 2008. The observatory now uses a refurbished 8-inch Reed refractor for visual observations of planets and stars. It also includes two Ash domes housing a 16" RCOS telescope and a refurbished Grubb refractor (originally purchased to observe the 1882 transit of Venus). Detectors include an SBIG ST-9E CCD camera and a DSS-7 spectrograph. There is an observing deck between the domes. The observatory also houses a digital planetarium theater, which uses a Spitz SciDomeHD projection system.

References

External links

Department of Astronomy at Yale University

Forecasts of observing conditions.
Leitner Family Observatory and Planetarium homepage
{{Authority control Astronomical observatories in Connecticut Yale University Yale University buildings 1830 establishments in Connecticut

History

See also

References

External links