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Rho3 Arietis
Rho3 Arietis (Rho3 Ari, ρ3 Arietis, ρ3 Ari) is the Bayer designation for a star in the northern constellation of Aries. It is faintly visible to the naked eye with an apparent visual magnitude of 5.63. Based upon an annual parallax shift of 28.29 mas, this star is located at a distance of approximately from Earth. This is an astrometric binary system. The visible component is an F-type main sequence star with a stellar classification of F6 V. It is around 2.4 billion years old and has a high abundance of elements other than hydrogen and helium when compared to the Sun. Name This star, along with δ Ari, ε Ari, ζ Ari, and π Ari, were Al Bīrūnī's ''Al Buṭain'' (ألبطين), the dual of ''Al Baṭn'', the Belly. According to the catalogue of stars in the ''Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars'', ''Al Buṭain'' were the title for five stars : δ Ari as ''Botein'', π Ari as ''Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a 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 celestial body, as they are subject to 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 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 bodies) can be used to generate an ephemeris, a table of values giving the positions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Visual Magnitude
Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's light caused by interstellar dust along the line of sight to the observer. The word ''magnitude'' in astronomy, unless stated otherwise, usually refers to a celestial object's apparent magnitude. The magnitude scale dates back to the ancient Roman astronomer Claudius Ptolemy, whose star catalog listed stars from 1st magnitude (brightest) to 6th magnitude (dimmest). The modern scale was mathematically defined in a way to closely match this historical system. The scale is reverse logarithmic: the brighter an object is, the lower its magnitude number. A difference of 1.0 in magnitude corresponds to a brightness ratio of \sqrt /math>, or about 2.512. For example, a star of magnitude 2.0 is 2.512 times as bright as a star of magnitude 3.0, 6. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hipparcos Objects
''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the first high-precision measurements of the intrinsic brightnesses (compared to the less precise apparent brightness), proper motions, and parallaxes of stars, enabling better calculations of their distance and tangential velocity. When combined with radial velocity measurements from spectroscopy, astrophysicists were able to finally measure all six quantities needed to determine the motion of stars. The resulting ''Hipparcos Catalogue'', a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision ''Tycho Catalogue'' of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. ''Hipp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Draper Catalogue Objects
Henry may refer to: People *Henry (given name) *Henry (surname) * Henry Lau, Canadian singer and musician who performs under the mononym Henry Royalty * Portuguese royalty ** King-Cardinal Henry, King of Portugal ** Henry, Count of Portugal, Henry of Burgundy, Count of Portugal (father of Portugal's first king) ** Prince Henry the Navigator, Infante of Portugal ** Infante Henrique, Duke of Coimbra (born 1949), the sixth in line to Portuguese throne * King of Germany **Henry the Fowler (876–936), first king of Germany * King of Scots (in name, at least) ** Henry Stuart, Lord Darnley (1545/6–1567), consort of Mary, queen of Scots ** Henry Benedict Stuart, the 'Cardinal Duke of York', brother of Bonnie Prince Charlie, who was hailed by Jacobites as Henry IX * Four kings of Castile: **Henry I of Castile **Henry II of Castile **Henry III of Castile **Henry IV of Castile * Five kings of France, spelt ''Henri'' in Modern French since the Renaissance to italianize the name and to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-type Main-sequence Stars
An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII and VIII. This temperature range gives the F-type stars a whitish hue when observed by the atmosphere. Because a main-sequence star is referred to as a dwarf star, this class of star may also be termed a yellow-white dwarf (not to be confused with white dwarfs, remnant stars that are a possible final stage of stellar evolution). Notable examples include Procyon A, Gamma Virginis A and B, and KIC 8462852. Spectral standard stars The revised Yerkes Atlas system (Johnson & Morgan 1953) listed a dense grid of F-type dwarf spectral standard stars; however, not all of these have survived to this day as stable standards. The ''anchor points'' of the MK spectral classification system among the F-type main-sequence dwarf stars, i.e. those st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monthly Notices Of The Royal Astronomical Society
''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes letters and papers reporting original research in relevant fields. Despite the name, the journal is no longer monthly, nor does it carry the notices of the Royal Astronomical Society. History The first issue of MNRAS was published on 9 February 1827 as ''Monthly Notices of the Astronomical Society of London'' and it has been in continuous publication ever since. It took its current name from the second volume, after the Astronomical Society of London became the Royal Astronomical Society (RAS). Until 1960 it carried the monthly notices of the RAS, at which time these were transferred to the newly established '' Quarterly Journal of the Royal Astronomical Society'' (1960–1996) and then to its successor journal '' Astronomy & Geophysics'' (since 1997). Until 1965, MNRAS wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pi Arietis
Pi Arietis, Latinized from π Arietis, is the Bayer designation for a multiple star system in the northern constellation of Aries. Based upon parallax measurements made during the Hipparcos mission, this system is approximately distant from Earth and has an apparent visual magnitude of 5.21. This is bright enough to be faintly seen with the naked eye. The primary member of this system is a massive, B-type main sequence star with a stellar classification of B6 V. It is a close spectroscopic binary with an orbital period of 3.854 days, an eccentricity of 0.04, and a combined visual magnitude of 5.30. At an angular separation of 3.28 arcseconds is a magnitude 8.46 A-type main sequence star with a classification of A0 Vp. Finally, a fourth member of the system is a magnitude 11.0 F-type main sequence star with a classification of F8V at an angular separation of 25.2 arcseconds from the primary. Name This star, along with δ Ari, ε Ari, ζ Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Arietis
Zeta Arietis, Latinized from ζ Arietis, is the Bayer designation for a star in the northern constellation of Aries. It is dimly visible to the naked eye with an apparent visual magnitude of +4.89. Based upon an annual parallax shift of 12.77 mas, the distance to this star is . This is an A-type main sequence star with a stellar classification of A1 V. It has a high rate of rotation with a projected rotational velocity of 133 km/s. The star is shining at an effective temperature of 9,500 K, giving it the characteristic white-hued glow of an A-type star. Name This star, along with δ Ari, ε Ari, π Ari, and ρ3 Ari, were Al Bīrūnī's ''Al Buṭain'' (ألبطين), the dual of ''Al Baṭn'', the Belly. According to the catalogue of stars in the ''Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars'', ''Al Buṭain'' were the title for five stars : δ Ari as ''Botein'', π Ari as ''Al Buṭain I'', ρ3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon Arietis
Epsilon Arietis (ε Ari, ε Arietis) is the Bayer designation for a visual binary star system in the northern constellation of Aries. It has a combined apparent visual magnitude of 4.63 and can be seen with the naked eye, although the two components are too close together to be resolved without a telescope. With an annual parallax shift of 9.81 mas, the distance to this system can be estimated as , give or take a 30 light-year margin of error. It is located behind the dark cloud MBM12. The brighter member of this pair has an apparent magnitude of 5.2. At an angular separation of from the brighter component, along a position angle of , is the magnitude 5.5 companion. Both are A-type main sequence stars with a stellar classification of A2 Vs. (The 's' suffix indicates that the absorption lines in the spectrum are distinctly narrow.) In the 2009 ''Catalogue of Ap, HgMn and Am stars'', the two stars have a classification of A3 Ti, indicating they are Ap star ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Arietis
Delta Arietis (δ Arietis, abbreviated Delta Ari, δ Ari), officially named Botein , is a star in the northern constellation of Aries, 1.8 degrees north of the ecliptic. The apparent visual magnitude is 4.35, so it is visible to the naked eye. It has an annual parallax shift of 19.22 mas; corresponding to a distance of about from the Sun. Nomenclature ''δ Arietis'' ( Latinised to ''Delta Arietis'') is the star's Bayer designation. It bore the traditional name ''Botein'' which is derived from Al Bīrūnī's ''Al Buṭayn'' (Arabic: البُطَين), the diminutive of ''Al Baṭn'', "the Belly". This is the name of a star association consisting of this star, Epsilon Arietis, Zeta Arietis, Pi Arietis, and Rho3 Arietis According to a 1971 NASA catalogue of stars, ''Al Buṭain'' was the title for five stars: Delta Arietis (listed as ''Botein''), Pi Arietis (as ''Al Buṭain I''), Rho3 Arietis (''Al Buṭain II''), Epsilon Arietis (''Al Buṭain III'') and Zeta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Classification
In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the rainbow of colors interspersed with spectral lines. Each line indicates a particular chemical element or molecule, with the line strength indicating the abundance of that element. The strengths of the different spectral lines vary mainly due to the temperature of the photosphere, although in some cases there are true abundance differences. The ''spectral class'' of a star is a short code primarily summarizing the ionization state, giving an objective measure of the photosphere's temperature. Most stars are currently classified under the Morgan–Keenan (MK) system using the letters ''O'', ''B'', ''A'', ''F'', ''G'', ''K'', and ''M'', a sequence from the hottest (''O'' type) to the coolest (''M'' type). Each letter class is then subdivi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-type Main Sequence Star
An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII and VIII. This temperature range gives the F-type stars a whitish hue when observed by the atmosphere. Because a main-sequence star is referred to as a dwarf star, this class of star may also be termed a yellow-white dwarf (not to be confused with white dwarfs, remnant stars that are a possible final stage of stellar evolution). Notable examples include Procyon A, Gamma Virginis A and B, and KIC 8462852. Spectral standard stars The revised Yerkes Atlas system (Johnson & Morgan 1953) listed a dense grid of F-type dwarf spectral standard stars; however, not all of these have survived to this day as stable standards. The ''anchor points'' of the MK spectral classification system among the F-type main-sequence dwarf stars, i.e. those st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
