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KIC 11145123
KIC 1145123 (sometimes mistakenly called Kepler 1145123), is a white hued star located in the northern constellation Cygnus, the swan. It has an apparent magnitude of 13.12, making it readily visible in large telescopes, but not to the naked eye. The object is located relatively far at a distance of approximately 3,910 light years, but is rapidly approaching the Solar System with a radial velocity of . Characteristics KIC 11145123 has a simple spectral classification of A, indicating that it is an A-type star. It has 1.71 times the mass of the Sun and 1.57 times its radius. It radiates 7.7 times the luminosity of the Sun from its photosphere at an effective temperature of . Unlike most hot stars, KIC 11145123 spins very slowly with a projected rotational velocity of . This corresponds to a period of roughly 100 days. Despite appearing as a main sequence star (Gaia DR3 models it as such), it is most likely a blue straggler A blue straggler is a main-sequence In astrono ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A-type Star
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V (five). These stars have spectra defined by strong hydrogen Balmer absorption lines. They measure between 1.4 and 2.1 solar masses () and have surface temperatures between 7,600 and 10,000 K. Bright and nearby examples are Altair (A7 V), Sirius A (A1 V), and Vega (A0 V). A-type stars do not have convective zones and thus are not expected to harbor magnetic dynamos. As a consequence, because they do not have strong stellar winds, they lack a means to generate X-ray emissions. In July 2019, astronomers reported finding an A-type star, S5-HVS1, traveling , faster than any other star detected so far. The star is in the Grus (or Crane) constellation in the southern sky, about 29,000 light-years from Earth, and may have been ejected out of the Milky Way after interacting with Sagittarius A*, the supermassive black hole at the center of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A-type Main-sequence Stars
A type or type A may refer to: * A-type asteroid, a type of relatively uncommon inner-belt asteroids * A type blood, a type in the ABO blood group system * A-type inclusion, a type of cell inclusion * A-type potassium channel, a type of voltage-gated potassium channel * A type proanthocyanidin, a specific type of flavonoids * A-type star, a class of stars * Type A Dolby Noise Reduction, a type of Dolby noise-reduction system * Type A climate, a type in the Köppen climate classification * Type A flu, a type of influenza virus * Type A evaluation of uncertainty, an uncertainty in measurement that can be inferred, for example, from repeated measurement * Type A (label), a music label that for example produced the 2004 album '' What Doesn't Kill You...'' by Candiria * Type A personality, a personality type in the Type A and Type B personality theory * Type A submarine, a class of submarines in the Imperial Japanese Navy which served during the Second World War * Hemophilia type A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Straggler
A blue straggler is a main-sequence In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hert ... star in an open cluster, open or globular cluster that is more luminosity, luminous and stellar classification, bluer than stars at the main sequence turnoff point for the cluster. Blue stragglers were first discovered by Allan Sandage in 1953 while performing photometry (astronomy), photometry of the stars in the globular cluster Messier 3, M3. Standard theories of stellar evolution hold that the position of a star on the Hertzsprung–Russell diagram should be determined almost entirely by the initial mass of the star and its age. In a cluster, stars all formed at approximately the same time, and thus in an H–R diagram for a cluster, all stars should lie along a clearly defined curve set by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaia DR3
The ''Gaia'' catalogues are star catalogues created using the results obtained by '' Gaia'' space telescope. The catalogues are released in stages that will contain increasing amounts of information; the early releases also miss some stars, especially fainter stars located in dense star fields. Data from every data release can be accessed at the ''Gaia'' archive. Initial Gaia Source List The Initial Gaia Source List (IGSL) is a star catalogue of 1.2 billion objects created in support of the ''Gaia'' mission. The mission should have delivered a catalogue based entirely on its own data. For the first catalogue, Gaia DR1, a way was needed to be able to assign the observations to an object and to compare them with the objects from other star catalogues. For this purpose, a separate catalog of objects from several other catalogues was compiled, which roughly represents the state of knowledge of astronomy at the beginning of the Gaia mission. Attitude Star Catalog The Attitude Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main Sequence Star
Main may refer to: Geography * Main River (other) **Most commonly the Main (river) in Germany *Main, Iran, a village in Fars Province *"Spanish Main", the Caribbean coasts of mainland Spanish territories in the 16th and 17th centuries *''The Main'', the diverse core running through Montreal, Quebec, Canada, also separating the Two Solitudes *Main (lunar crater), located near the north pole of the Moon *Main (Martian crater) People and organisations * Main (surname), a list of people with this family name *Ma'in, alternate spelling for the Minaeans, an ancient people of modern-day Yemen *Main (band), a British ambient band formed in 1991 * Chas. T. Main, an American engineering and hydroelectric company founded in 1893 *MAIN (Mountain Area Information Network), former operator of WPVM-LP (MAIN-FM) in Asheville, North Carolina, U.S. Ships * ''Main'' (ship), an iron sailing ship launched in 1884 * SS ''Main'', list of steamships with this name * ''Main'' (A515), a modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Days
A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours, 1440 minutes, or 86,400 seconds. In everyday life, the word "day" often refers to a solar day, which is the length between two solar noons or times the Sun reaches the highest point. The word "day" may also refer to ''daytime'', a time period when the location receives direct and indirect sunlight. On Earth, as a location passes through its day, it experiences morning, noon, afternoon, evening, and night. The effect of a day is vital to many life processes, which is called the circadian rhythm. A collection of sequential days is organized into calendars as dates, almost always into weeks, months and years. Most calendars' arrangement of dates use either or both the Sun with its four seasons (solar calendar) or the Moon's phasing (lunar calendar). The start of a day is commonly accepted as roughly the time of the middle of the night or midnight, written as 00:00 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Projected Rotational Velocity
Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface. The rotation of a star produces an equatorial bulge due to centrifugal force. As stars are not solid bodies, they can also undergo differential rotation. Thus the equator of the star can rotate at a different angular velocity than the higher latitudes. These differences in the rate of rotation within a star may have a significant role in the generation of a stellar magnetic field. The magnetic field of a star interacts with the stellar wind. As the wind moves away from the star its rate of angular velocity slows. The magnetic field of the star interacts with the wind, which applies a drag to the stellar rotation. As a result, angular momentum is transferred from the star to the wind, and over time this gradually slows the star's rate of rotation. Measurement Unless a star is being obse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effective Temperature
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature when the body's emissivity curve (as a function of wavelength) is not known. When the star's or planet's net emissivity in the relevant wavelength band is less than unity (less than that of a black body), the actual temperature of the body will be higher than the effective temperature. The net emissivity may be low due to surface or atmospheric properties, including greenhouse effect. Star The effective temperature of a star is the temperature of a black body with the same luminosity per ''surface area'' () as the star and is defined according to the Stefan–Boltzmann law . Notice that the total (bolometric) luminosity of a star is then , where is the stellar radius. The definition of the stellar radius is obviously not straightf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosphere
The photosphere is a star's outer shell from which light is radiated. The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it being a spherical surface that is perceived to emit light. It extends into a star's surface until the plasma becomes opaque, equivalent to an optical depth of approximately , or equivalently, a depth from which 50% of light will escape without being scattered. A photosphere is the deepest region of a luminous object, usually a star, that is transparent to photons of certain wavelengths. Temperature The surface of a star is defined to have a temperature given by the effective temperature in the Stefan–Boltzmann law. Stars, except neutron stars, have no solid or liquid surface. Therefore, the photosphere is typically used to describe the Sun's or another star's visual surface. Composition of the Sun The Sun is composed primarily of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminosity Of The Sun
The solar luminosity (), is a unit of radiant flux (power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun. One nominal solar luminosity is defined by the International Astronomical Union to be . This does not include the solar neutrino luminosity, which would add , or , i.e. a total of (the mean energy of the solar photons is 26 MeV and that of the solar neutrinos 0.59 MeV, i.e. 2.27%; the Sun emits photons and as many neutrinos each second, of which per m2 reach the Earth each second). The Sun is a weakly variable star, and its actual luminosity therefore fluctuates. The major fluctuation is the eleven-year solar cycle (sunspot cycle) that causes a quasi-periodic variation of about ±0.1%. Other variations over the last 200–300 years are thought to be much smaller than this. Determination Solar luminosity is related to solar irradiance (the solar c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Radius
Solar radius is a unit of distance used to express the size of stars in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3: :1\,R_ = 6.957\times 10^8 \hbox is approximately 10 times the average radius of Jupiter, about 109 times the radius of the Earth, and 1/215th of an astronomical unit, the distance of the Earth from the Sun. It varies slightly from pole to equator due to its rotation, which induces an oblateness in the order of 10 parts per million. Measurements The unmanned SOHO spacecraft was used to measure the radius of the Sun by timing transits of Mercury across the surface during 2003 and 2006. The result was a measured radius of . Haberreiter, Schmutz & Kosovichev (2008) determined the radius corresponding to the solar photosphere to be . This new value is consistent with helioseismic estimates; the same study showed that previous estimates using inflection poin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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