5335 Damocles is the archetype of the Damocloids, astroids that are inactive nuclei of Halley Family and long period comets. February 18 is the 49th day of the year in the Gregorian Calendar. ... 1991 (MCMXCI) is a common year starting on Tuesday of the Gregorian calendar. ... The provisional designation of comets and asteroids are similar to each other: they both follow a pattern set in 1925 by the Minor Planet Center of the IAU. Historical designations At first, astronomers strove to assign symbols to the minor planets: 1 Ceres a stylized sickle 2 Pallas a lozenge... Minor planets, or planetoids are minor bodies of the Solar system orbiting the Sun (or of other planetary systems orbiting other stars) that are larger than meteoroids (the largest of which might be taken to be around 10 meters or so across) but smaller than major planets (Mercury having a... Damocloids are asteroids such as 5335 Damocles and 1996 PW that have long-period highly eccentric orbits typical of periodic comets such as 1P/Halley, but without showing a cometary coma or tail. ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... January 1 is the first day of the calendar year in both the Julian and Gregorian calendars. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... The Julian day or Julian day number (JDN) is the number of days that have elapsed since 12 noon Greenwich Mean Time (UT or TT) on Monday, January 1, 4713 BC in the proleptic Julian calendar . ... In astrodynamics, under standard assumptions any orbit must be of conic section shape. ... In geometry, the semi-major axis (also semimajor axis) a applies to ellipses and hyperbolas. ... The astronomical unit (AU or au or a. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... A day (symbol: d) is a unit of time equal to 24 hours. ... In astronomy, a Julian year is a unit of time defined as exactly 365. ... The orbital speed of a body, generally a planet, a natural satellite, an artificial satellite, or a multiple star, is the speed at which it orbits around the barycenter of a system, usually around a more massive body. ... Inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit and is the angular distance of the orbital plane from the plane of the reference (usually planets equator or the ecliptic), stated in degrees. ... A degree (in full, a degree of arc, arc degree, or arcdegree), usually symbolized °, is a measurement of plane angle, representing 1／360 of a full rotation. ... The Longitude of the ascending node () is one of the orbital elements used to specify the orbit of an object in space. ... The argument of the perihelion is one of the orbital elements describing the orbit of a planet. ... In the study of orbital dynamics the mean anomaly is a measure of time, specific to the orbiting body p, which is a multiple of 2π radians at and only at periapsis. ... For the majority of numbered asteroids, almost nothing is known apart from a few physical parameters. ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... ... In physics, for a given gravitational field and a given position, the escape velocity is the minimum speed an object without propulsion, at that position, needs to have to move away indefinitely from the source of the field, as opposed to falling back or staying in an orbit within a... In astronomy, a rotation period is the time an astronomical object takes to complete one revolution around its rotation axis. ... The hour (symbol: h) is a unit of time. ... Asteroids are assigned a type based on spectral shape, color, and sometimes albedo. ... In astronomy, absolute magnitude is the apparent magnitude, m, an object would have if it were at a standardized distance away. ... The albedo is a measure of reflectivity of a surface or body. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Damocloids are asteroids such as 5335 Damocles and 1996 PW that have long-period highly eccentric orbits typical of periodic comets such as 1P/Halley, but without showing a cometary coma or tail. ...

references

• Catchall Catalog of Minor Planets
• AstDys
• JPL neo page, including orbit diagrams
• for JPL Horizons telnet version is most comprehensive

See also: List of asteroids This is a list of numbered asteroids, in sequential order. ...