1822 Waterman, provisional designation , is a stony

asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

from the inner regions of the

asteroid belt The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids ...

, approximately 6.5 kilometers in diameter. It was discovered on 25 July 1950, by Indiana University's

Indiana Asteroid Program The Indiana Asteroid Program was a photographic astronomical survey of asteroids during 1949–1967, at the U.S. Goethe Link Observatory near Brooklyn, Indiana, Brooklyn, Indiana. The program was initiated by Frank K. Edmondson of Indiana Universi ...

at its

Goethe Link Observatory The Goethe Link Observatory, observatory code 760, is an astronomical observatory near Brooklyn, Indiana, United States. It is owned by Indiana University and operated by the Indiana Astronomical Society https://iasindy.org/about.html, which eff ...

near Brooklyn, Indiana, United States. The asteroid was named after American physicist

Alan T. Waterman Alan Tower Waterman (June 4, 1892 – November 30, 1967) was an American physicist. Biography Born in Cornwall-on-Hudson, New York, he grew up in Northampton, Massachusetts. His father was a professor of physics at Smith College Smith Coll ...

Orbit and classification

''Waterman'' is a

S-type asteroid S-type (stony-type or silicaceous-type) asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are ...

. It orbits the Sun in the inner main-belt at a distance of 1.8–2.5 AU once every 3 years and 2 months (1,168 days). Its orbit has an

eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-Centre (geometry), center, in geometry * Eccentricity (g ...

of 0.15 and an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

of 1 ° with respect to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of Earth's orbit, Earth around the Sun. It was a central concept in a number of ancient sciences, providing the framework for key measurements in astronomy, astrology and calendar-making. Fr ...

. The body's

observation arc In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...

begins with its official discovery observation, as its first identification, , made at the German

Sonneberg Observatory Sonneberg Observatory () is an astronomical observatory located at 638 m altitude on Erbisbühl in the Neufang district of Sonneberg, Germany. The observatory was founded in 1925 on the initiative of Cuno Hoffmeister by the town of Sonneber ...

in 1943, remained unused.

Physical characteristics

Rotation period

In January 2013, a rotational

lightcurve In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...

of ''Waterman'' was obtained from photometric observation taken at the U.S Etscorn Observatory in New Mexico. It gave a well-defined

rotation period In astronomy, the rotation period or spin period of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the '' sidereal rotation period'' (or ''sidereal day''), i.e., the time that the objec ...

of 7.581 hours with a brightness variation of 0.51

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

().

Diameter and albedo

According to the survey carried out by NASA's

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, List of observatory codes, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy Space observatory, space telescope in the Explorers Program launched in December 2009.. . WISE L ...

with its subsequent

NEOWISE Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy space telescope in the Explorers Program launched in December 2009.. . WISE discovered thousands of minor planets and nu ...

mission, ''Waterman'' measures between 6.06 and 6.52 kilometers in diameter, and its surface has an

albedo Albedo ( ; ) is the fraction of sunlight that is Diffuse reflection, diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects ...

between 0.264 and 0.325. The ''Collaborative Asteroid Lightcurve Link'' assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 7.46 kilometers with an absolute magnitude of 13.1.

Naming

This

minor planet According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor ...

was named in honor of American physicist

Alan Tower Waterman Alan Tower Waterman (June 4, 1892 – November 30, 1967) was an American physicist. Biography Born in Cornwall-on-Hudson, New York, he grew up in Northampton, Massachusetts. His father was a professor of physics at Smith College. Alan also bec ...

(1892–1967), who was the first director of the U.S.

National Science Foundation The U.S. National Science Foundation (NSF) is an Independent agencies of the United States government#Examples of independent agencies, independent agency of the Federal government of the United States, United States federal government that su ...

. He went to Washington to serve with OSRD (1941–45), ONR (1946–51), and NSF (1951–63), after being an academic physicist for 25 years. Waterman was awarded the Karl Taylor Compton Gold Medal for distinguished statesmanship in science, the

Public Welfare Medal The Public Welfare Medal is awarded by the U.S. National Academy of Sciences "in recognition of distinguished contributions in the application of science to the public welfare." It is the most prestigious honor conferred by the academy. First awar ...

and the

Presidential Medal of Freedom The Presidential Medal of Freedom is the highest civilian award of the United States, alongside the Congressional Gold Medal. It is an award bestowed by decision of the president of the United States to "any person recommended to the President ...

. The official was published by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Funct ...

on 1 June 1975 ().

References

External links

Asteroid Lightcurve Database (LCDB)
query form

)
Dictionary of Minor Planet Names
Google books

– Observatoire de Genève, Raoul Behrend

– Minor Planet Center * * {{DEFAULTSORT:Waterman 001822 001822 Named minor planets 19500725