1750 Eckert, provisional designation , is a stony slow rotating Hungaria

asteroid An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. ...

and

Mars-crosser A Mars-crossing asteroid (MCA, also Mars-crosser, MC) is an asteroid whose orbit crosses that of Mars. Some Mars-crossers numbered below 100000 are listed here. They include the two numbered Mars trojans 5261 Eureka and . Many databases, for i ...

from the inner regions of the

asteroid belt The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...

, approximately 7 kilometers in diameter. It was discovered on 15 July 1950, by German astronomer

Karl Reinmuth Karl Wilhelm Reinmuth (4 April 1892 in Heidelberg – 6 May 1979 in Heidelberg) was a German astronomer and a prolific discoverer of 395 minor planets. Scientific career From 1912 to 1957, Reinmuth was working as an astronomer at the Lande ...

Heidelberg Observatory Heidelberg (; Palatine German: ') is a city in the German state of Baden-Württemberg, situated on the river Neckar in south-west Germany. As of the 2016 census, its population was 159,914, of which roughly a quarter consisted of students. ...

in southern Germany. It was named after American astronomer

Wallace Eckert Wallace John Eckert (June 19, 1902 – August 24, 1971) was an American astronomer, who directed the Thomas J. Watson Astronomical Computing Bureau at Columbia University which evolved into the research division of IBM. Life Wallace John Eckert ...

Classification and orbit

The Mars crossing asteroid is also a member of the

Hungaria family The Hungaria asteroids, also known as the Hungaria group, are a dynamical group of asteroids in the asteroid belt which orbit the Sun with a semi-major axis (longest radius of an ellipse) between 1.78 and 2.00 astronomical units (AU). They are t ...

, a group that forms the innermost dense concentration of asteroids in the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar S ...

. It orbits the Sun at a distance of 1.6–2.3 AU once every 2 years and 8 months (977 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-center, in geometry * Eccentricity (graph theory) of a v ...

of 0.17 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 Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

of 19 ° with respect to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic again ...

. As no

precoveries In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of an object in images or photographic plates predating its discovery, typically for the purpose of calculating a more accurate orbit. This happens mos ...

were taken, and no prior identifications were made, ''Eckert''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.

Rotation period

In October 2009, a rotational

lightcurve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequ ...

of ''Eckert'' was obtained by American astronomer Brian Warner at his Palmer Divide Observatory () in Colorado. It gave an exceptionally long

rotation period The rotation period of a celestial object (e.g., star, gas giant, planet, moon, asteroid) may refer to its sidereal rotation period, i.e. the time that the object takes to complete a single revolution around its axis of rotation relative to the ...

of 375 hours with a brightness variation of 0.87

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 ...

(). A modeled lightcurve obtained from the Lowell Photometric Database in 2016, gave a similar period of 377.5 hours (). ''Eckert'' has the sixth-longest

of all known Mars-crossers.

Diameter and albedo

According to the survey carried out by the Japanese

Akari Akari (ASTRO-F) was an infrared astronomy Infrared astronomy is a sub-discipline of astronomy which specializes in the observation and analysis of astronomical objects using infrared (IR) radiation. The wavelength of infrared light ranges f ...

satellite, the asteroid measures 6.95 kilometers in diameter, and its surface has an

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

of 0.203. The ''Collaborative Asteroid Lightcurve Link'' agrees with Akarai and assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 6.97 kilometers with an

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse Logarithmic scale, logarithmic Magnitude (astronomy), astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent mag ...

of 13.15.

Naming

The

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 memory of American astronomer

(1902–1971), director at the

United States Naval Observatory United States Naval Observatory (USNO) is a scientific and military facility that produces geopositioning, navigation and timekeeping data for the United States Navy and the United States Department of Defense. Established in 1830 as the Depo ...

from 1940 to 1945, president of

IAU The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...

's Commission 7, and pioneer in the use of automatic computing machines. In the late 1940s and early 1950s, he used the then most powerful computing machines ever built, SSEC and

NORC NORC may refer to: Organizations * NORC (web service), a street view web service and company based in Romania * Guerrilla Army of the Poor, which went by the acronym NORC in its beginnings * National Opinion Research Center (NORC) at the Universit ...

, for astronomical calculations. The asteroid 1625 The NORC was named after one of these early super-computers. Eckert also produced the integration of the orbits of the five outer planets in collaboration with Brouwer and Clemence, after whom the minor planets

1746 Brouwer 1746 Brouwer ( ''prov. designation'': ) is a Hilda asteroid from the outermost region of the asteroid belt, approximately 64 kilometers in diameter. It was discovered on 14 September 1963, by IU's Indiana Asteroid Program at Goethe Link Observat ...

and

1919 Clemence 1919 Clemence, provisional designation , is a bright Hungaria asteroid and suspected tumbler from the inner regions of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 16 September 1971, by American astronomer James ...

were named. By use of sophisticated computing techniques, Eckert was able to check and extend Brown's

lunar theory Lunar theory attempts to account for the motions of the Moon. There are many small variations (or perturbations) in the Moon's motion, and many attempts have been made to account for them. After centuries of being problematic, lunar motion can now ...

''(also see

1643 Brown Events January–March * January 21 – Abel Tasman sights the island of Tonga. * February 6 – Abel Tasman sights the Fiji Islands. * March 13 – First English Civil War: First Battle of Middlewich – Roundhead ...

)''. 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. Function ...

on 20 February 1976 ().

Classification and orbit

Rotation period

Diameter and albedo

Naming

References

External links