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4090 Říšehvězd
4090 Říšehvězd, provisional designation , is a stony asteroid from the inner regions of the asteroid belt, approximately 7 kilometers in diameter. It was discovered by Czech astronomer Antonín Mrkos at Kleť Observatory on 2 September 1986. Named for the astronomy journal Říše hvězd, it is known as having had the most diacritics in its name among all named minor planets before the naming of 229762 Gǃkúnǁʼhòmdímà. Classification and orbit The S-type asteroid orbits the Sun at a distance of 1.9–2.9 AU once every 3 years and 7 months (1,322 days). Its orbit has an eccentricity of 0.21 and an inclination of 1 ° with respect to the ecliptic. The first observation was made at the U.S. Yerkes Observatory in 1931, extending the asteroid's observation arc by 55 years prior to its official discovery. Physical characteristics In 2009 and 2014, several rotational lightcurves were obtained for this asteroid at the Palomar Transient Factory. They gave a conc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antonín Mrkos
Antonín Mrkos () (27 January 1918 – 29 May 1996) was a Czech astronomer. Biography Mrkos entered the University in Brno in 1938. His studies were interrupted by the onset of World War II, and in 1945 he became a staff member at the Skalnaté Pleso Observatory in Czechoslovakia (now in Slovakia). It was from here that he carried out his extremely active cometary programme and became the discoverer of several unusual comets, the most famous of them the bright Comet 1957d. He was the second Czech in Antarctica and the first Czechoslovak to reach the Southern Pole of Inaccessibility as a member of the 3rd Soviet Antarctic Expedition (1957–1959). The Czechoslovak flag was the second flag raised after the flag of the USSR. He returned to Antarctica as the head of the four-member Czechoslovak crew in the seventh Soviet Antarctic Expedition (1961–1963). He was studying auroras among other things. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Eccentricity
In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit (or capture orbit), and greater than 1 is a hyperbola. The term derives its name from the parameters of conic sections, as every Kepler orbit is a conic section. It is normally used for the isolated two-body problem, but extensions exist for objects following a rosette orbit through the Galaxy. Definition In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a non-negative number that defines its shape. The eccentricity may take the following values: * Circular orbit: * Elliptic orbit: * Parabolic trajectory: * Hyperbolic trajectory: The eccentricity is given by e = \sqrt where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 planet'', but that year's meeting IAU definition of planet, reclassified minor planets and comets into dwarf planets and Small Solar System body, small Solar System bodies (SSSBs).Press release, IAU 2006 General Assembly: Result of the IAU Resolution votes International Astronomical Union, August 24, 2006. Accessed May 5, 2008. In contrast to the eight official planets of the Solar System, all minor planets fail to clearing the neighborhood, clear their orbital neighborhood. Minor planets include asteroids (near- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Albedo
Albedo ( ; ) is the fraction of sunlight that is 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 all incident radiation). ''Surface albedo'' is defined as the ratio of radiosity ''J''e to the irradiance ''E''e (flux per unit area) received by a surface. The proportion reflected is not only determined by properties of the surface itself, but also by the spectral and angular distribution of solar radiation reaching the Earth's surface. These factors vary with atmospheric composition, geographic location, and time (see position of the Sun). While directional-hemispherical reflectance factor is calculated for a single angle of incidence (i.e., for a given position of the Sun), albedo is the directional integration of reflectance over all solar angles in a given period. The temporal resolution may range from seconds (as obtained from flux measurements) to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 List of minor planet discoverers#WISE, discovered thousands of minor planets and numerous star clusters. Its observations also supported the discovery of the first Y dwarf, Y-type brown dwarf and Earth trojan, Earth trojan asteroid. ... . WISE performed an all-sky astronomical survey with images in 3.4, 4.6, 12 and 22 μm wavelength range bands, over ten months using a diameter infrared telescope in Geocentric orbit, Earth orbit. After its solid hydrogen coolant depleted, it was placed in Hibernation (spaceflight), hibernation mode in February 2011. In 2013, NASA reactivated the WISE telescope to search for near-Earth objects (NEO), such as comets and asteroids, that could collide with Earth. The reactivation mission was called Near-Eart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 numerous star clusters. Its observations also supported the discovery of the first Y-type brown dwarf and Earth trojan asteroid. ... . WISE performed an all-sky astronomical survey with images in 3.4, 4.6, 12 and 22 μm wavelength range bands, over ten months using a diameter infrared telescope in Earth orbit. After its solid hydrogen coolant depleted, it was placed in hibernation mode in February 2011. In 2013, NASA reactivated the WISE telescope to search for near-Earth objects (NEO), such as comets and asteroids, that could collide with Earth. The reactivation mission was called Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE). As of August 2023, NEOWISE was 40% through the 20th coverage of the full sky. Science o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LCDB Quality Code
In astronomy, a light curve is a graph of the 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 frequency interval or band. Light curves can be periodic, as in the case of eclipsing binaries, Cepheid variables, other periodic variables, and transiting extrasolar planets; or aperiodic, like the light curve of a nova, cataclysmic variable star, supernova, microlensing event, or binary as observed during occultation events. The study of a light curve and other observations can yield considerable information about the physical process that produces such a light curve, or constrain the physical theories about it. Variable stars Graphs of the apparent magnitude of a variable star over time are commonly used to visualise and analyse their behaviour. Although the categorisation of variable star types is increasingly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnitude (astronomy)
In astronomy, magnitude is a measure of the brightness of an astronomical object, object, usually in a defined passband. An imprecise but systematic determination of the magnitude of objects was introduced in ancient times by Hipparchus. Magnitude values do not have a unit. The scale is Logarithmic scale, logarithmic and defined such that a magnitude 1 star is exactly 100 times brighter than a magnitude 6 star. Thus each step of one magnitude is \sqrt[5] \approx 2.512 times brighter than the magnitude 1 higher. The brighter an object appears, the lower the value of its magnitude, with the brightest objects reaching negative values. Astronomers use two different definitions of magnitude: apparent magnitude and absolute magnitude. The ''apparent'' magnitude () is the brightness of an object and depends on an object's intrinsic luminosity, its Cosmic distance ladder, distance, and the Extinction (astronomy), extinction reducing its brightness. The ''absolute'' magnitude () describes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 object takes to complete a full rotation around its axis relative to the background stars ( inertial space). The other type of commonly used "rotation period" is the object's '' synodic rotation period'' (or ''solar day''), which may differ, by a fraction of a rotation or more than one rotation, to accommodate the portion of the object's orbital period around a star or another body during one day. Measuring rotation For solid objects, such as rocky planets and asteroids, the rotation period is a single value. For gaseous or fluid bodies, such as stars and giant planets, the period of rotation varies from the object's equator to its pole due to a phenomenon called differential rotation. Typically, the stated rotation period for a giant pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palomar Transient Factory
The Palomar Transient Factory (PTF, obs. code: I41), was an astronomical survey using a wide-field survey camera designed to search for optical transient and variable sources such as variable stars, supernovae, asteroids and comets. The project completed commissioning in summer 2009, and continued until December 2012. It has since been succeeded by the Intermediate Palomar Transient Factory (iPTF), which itself transitioned to the Zwicky Transient Facility in 2017/18. All three surveys are registered at the MPC under the same observatory code for their astrometric observations. Description The fully automated system included an automated realtime data reduction pipeline, a dedicated photometric follow-up telescope, and a full archive of all detected astronomical sources. The survey was performed with a 12K × 8K, 7.8 square degree CCD array camera re-engineered for the 1.2-meter Samuel Oschin Telescope at Palomar Observatory. The survey camera achieved fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 and with time on the ''x''-axis. The light is usually in a particular frequency interval or frequency band, band. Light curves can be periodic, as in the case of eclipsing binary, eclipsing binaries, Cepheid variables, other periodic variables, and Methods of detecting extrasolar planets#Transit photometry, transiting extrasolar planets; or aperiodic, like the light curve of a nova, cataclysmic variable star, supernova, gravitational microlensing, microlensing event, or binary as observed during occultation events. The study of a light curve and other observations can yield considerable information about the physical process that produces such a light curve, or constrain the physical theories about it. Variable stars Graphs of the ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 used in the discovery and tracking of asteroids and comets. Arc length has the greatest influence on the accuracy of an orbital estimate. The number, spacing of intermediate observations, and timestamps have a lesser effect. Short arcs A very short arc leaves a high uncertainty parameter. The object might be in one of many different orbits, at many distances from Earth. In some cases, the initial arc was too short to determine if the object was in orbit around the Earth, or orbiting out in the asteroid belt. With a 1-day observation arc, was thought to be a trans-Neptunian dwarf planet, but is now known to be a 1 km main-belt asteroid. With an observation arc of 3 days, was thought to be a Mars-crossing asteroid that could be a thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
