6312 Robheinlein ('' prov. designation:'' ) is a bright Augusta or

background asteroid An asteroid family is a population of asteroids that share similar proper orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. A ...

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 ...

, that measures approximately in diameter. It was discovered on 14 September 1990, by American astronomer Henry Holt at the

Palomar Observatory Palomar Observatory is an astronomical research observatory in San Diego County, California, United States, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...

in California. The uncommon

L-type asteroid L-type asteroids are relatively uncommon asteroids with a strongly reddish spectrum shortwards of 0.75 μm, and a featureless flat spectrum longwards of this. In comparison with the K-type asteroid, K-type, they exhibit a more reddish spectrum at ...

was named for American science fiction writer Robert A. Heinlein.

Orbit and classification

When applying the hierarchical clustering method to the asteroid's

proper orbital elements __NOTOC__ The proper orbital elements or proper elements of an orbit are constants of motion of an object in space that remain practically unchanged over an astronomically long timescale. The term is usually used to describe the three quantiti ...

, ''Robheinlein'' is considered to be a member of the Augusta family (as per Zappalà) as well as a non-

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

asteroid from the main belt's background population (as per Nesvorný). It orbits the Sun in the inner asteroid belt at a distance of 2.0–2.3 AU once every 3 years and 3 months (1,179 days;

semi-major axis In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the lo ...

of 2.18 AU). 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 ...

of 0.07 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 4 ° 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 agai ...

. 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 first observation as at the

Kleť Observatory Kleť Observatory ( cz, Hvězdárna Kleť; obs. code: 046) is an astronomical observatory in the Czech Republic. It is situated in South Bohemia, south of the summit of Mount Kleť, near the town of České Budějovice. Constructed in 1957, the ...

in January 1982, more than 8 years prior to its official discovery observation at Palomar.

Naming

Based on a suggestion by Belgian amateur astronomer

Jean Meeus Jean Meeus (born 12 December 1928) is a Belgian meteorologist and amateur astronomer specializing in celestial mechanics, spherical astronomy, and mathematical astronomy. Meeus studied mathematics at the University of Leuven in Belgium, w ...

, 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 '' ...

was named after

Robert Anson Heinlein Robert Anson Heinlein (; July 7, 1907 – May 8, 1988) was an American science fiction author, aeronautical engineer, and naval officer. Sometimes called the "dean of science fiction writers", he was among the first to emphasize scientific a ...

(1907–1988), the Dean of Science Fiction, author of the mainstream literary classic

Stranger in a Strange Land ''Stranger in a Strange Land'' is a 1961 science fiction novel by American author Robert A. Heinlein. It tells the story of Valentine Michael Smith, a human who comes to Earth in early adulthood after being born on the planet Mars and raised by ...

, and

science fiction Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imagination, imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, Paral ...

novels

Starship Troopers ''Starship Troopers'' is a military science fiction novel by American writer Robert A. Heinlein. Written in a few weeks in reaction to the US suspending nuclear tests, the story was first published as a two-part serial in '' The Magazine o ...

and

The Moon is a Harsh Mistress ''The Moon Is a Harsh Mistress'' is a 1966 science fiction novel by American writer Robert A. Heinlein about a lunar colony's revolt against absentee rule from Earth. The novel illustrates and discusses libertarian ideals. It is respected for it ...

. The official naming citation 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 13 April 2006 (). Heinlein helped narrate The Moon Landing with

Walter Cronkite Walter Leland Cronkite Jr. (November 4, 1916 – July 17, 2009) was an American broadcast journalist who served as anchorman for the ''CBS Evening News'' for 19 years (1962–1981). During the 1960s and 1970s, he was often cited as "the mo ...

on CBS in 1969, was involved in the planning of the Star Wars Defense program in the 1980s, contributed the words Waldo and

Grok ''Grok'' is a neologism coined by American writer Robert A. Heinlein for his 1961 science fiction novel ''Stranger in a Strange Land''. While the ''Oxford English Dictionary'' summarizes the meaning of ''grok'' as "to understand intuitively or ...

to the English language, and popularized the phrases Space Marine, TANSTAAFL, and

Pay it Forward Pay it forward is an expression for describing the beneficiary of a good deed repaying the kindness to others instead of to the original benefactor. The concept is old, but the particular phrase may have been coined by Lily Hardy Hammond in her 1 ...

Physical characteristics

''Robheinlein'' is an

in the SDSS-based taxonomy. It has an

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it we ...

of 14.1. As of 2018, no 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 ...

has been obtained from photometric observations. The body's

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 ...

pole Pole may refer to: Astronomy *Celestial pole, the projection of the planet Earth's axis of rotation onto the celestial sphere; also applies to the axis of rotation of other planets * Pole star, a visible star that is approximately aligned with th ...

and shape remain unknown.

Diameter and albedo

According to the survey carried out by the

NEOWISE Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 20 ...

mission of NASA's

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 2 ...

, ''Robheinlein'' measures 3.588 kilometers in diameter and its surface has a high

albedo Albedo (; ) is the measure of the diffuse reflection of 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 that refl ...

of 0.314.

References

}

External links

Lightcurve Database Query
(LCDB), at ''www.minorplanet.info''
Dictionary of Minor Planet Names
Google books

– Minor Planet Center * * {{DEFAULTSORT:Robheinlein 006312 006312 Discoveries by Henry E. Holt Named minor planets 19900914