2608 Seneca, provisional designation , is a stony

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 sub-kilometer

near-Earth object A near-Earth object (NEO) is any small Solar System body whose orbit brings it into proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). ...

of the

Amor group Amor Group was Scotland's largest independent business technology company before being acquired by Lockheed Martin in September 2013. The business was formed after a £28 million management buyout of Glasgow based Real Time Engineering Ltd. an ...

, approximately 0.9 kilometers in diameter. It was discovered on 17 February 1978, by German astronomer Hans-Emil Schuster at

ESO The European Organisation for Astronomical Research in the Southern Hemisphere, commonly referred to as the European Southern Observatory (ESO), is an intergovernmental research organisation made up of 16 member states for ground-based ast ...

La Silla Observatory La Silla Observatory is an astronomy, astronomical observatory in Chile with three telescopes built and operated by the European Southern Observatory (ESO). Several other telescopes are located at the site and are partly maintained by ESO. The obse ...

in northern Chile, and named after Roman philosopher

Seneca Seneca may refer to: People and language * Seneca (name), a list of people with either the given name or surname * Seneca people, one of the six Iroquois tribes of North America ** Seneca language, the language of the Seneca people Places Extrat ...

Orbit

''Seneca'' orbits the Sun at a distance of 1.1–4.0 AU once every 3 years and 12 months (1,457 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 0.57 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 15 ° 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 ...

. 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 in 1978, 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.

Close approaches

''Seneca'' has an ''Earth

minimum orbital intersection distance Minimum orbit intersection distance (MOID) is a measure used in astronomy to assess potential close approaches and collision risks between astronomical objects. It is defined as the distance between the closest points of the osculating orbits of ...

'' of , which corresponds to 51.5 lunar distances. On 22 March 2062, it will pass from the Earth.

Physical characteristics

In the

Tholen Tholen () is a 25,000 people municipality in the southwest of the Netherlands. The municipality of Tholen takes its name from the town of Tholen, which is the largest population center in the municipality. The municipality consists of two peninsu ...

taxonomy, ''Seneca'' is a stony

S-type asteroid S-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 of this type, making it the second ...

Photometry

In March 1978, a photometric observations taken by Degewij and Lebofsky at the

Lunar and Planetary Laboratory The Lunar and Planetary Laboratory (LPL) is a research center for planetary science located in Tucson, Arizona. It is also a graduate school, constituting the Department of Planetary Sciences at the University of Arizona. LPL is one of the wo ...

, Arizona, using a 154-cm reflector, gave 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 ...

with a

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 8 hours and a brightness amplitude of 0.4 (0.5)

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 ...

().

Radiometry

In addition, radiometric observations by L. and M. Lebofsky with the 71-cm reflector gave a mean-diameter of kilometers and

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 .

Diameter and albedo

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 ...

classifies ''Seneca'' as an object larger than 1 kilometer ("1+ KM Near-Earth Object"), while ''Collaborative Asteroid Lightcurve Link'' derives an albedo of 0.20 and a diameter of 0.9 kilometers based on 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 17.59. In 1994, astronomer

Tom Gehrels Anton M.J. "Tom" Gehrels (February 21, 1925 – July 11, 2011) was a Dutch–American astronomer, Professor of Planetary Sciences, and Astronomer at the University of Arizona, Tucson. Biography Youth and education Gehrels was born at Haa ...

published a diameter of 0.9 kilometers with an albedo of 0.21 in his ''Hazards Due to Comets and Asteroids''.

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 after Roman philosopher and statesman

Lucius Annaeus Seneca Lucius Annaeus Seneca the Younger (; 65 AD), usually known mononymously as Seneca, was a Stoic philosopher of Ancient Rome, a statesman, dramatist, and, in one work, satirist, from the post-Augustan age of Latin literature. Seneca was born in ...

(c. 4 BC – AD 65), also known as "Seneca the Younger" or simply "Seneca". The approved naming citation was published by the

on 8 April 1982 (). The lunar crater ''

'' was also named in his honor.