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Beta Apodis
Beta Apodis is a star in the southern circumpolar constellation of Apus. Its identifier is a Bayer designation that is Romanization of Greek, Latinized from β Apodis, and abbreviated Bet Aps or β Aps, respectively. The apparent visual magnitude of this star is +4.24, which is bright enough to be seen with the naked eye. It is located at a distance of approximately from Earth, as determined by stellar parallax, parallax measurements. The star is drifting closer with a heliocentric radial velocity of −30 km/s. The stellar spectrum, spectrum of this star matches a stellar classification of K0 III, which, according to models of stellar evolution, indicates that it is in the giant star stage, having exhausted the supply of hydrogen at its stellar core, core. The measured angular diameter of this star is . At the estimated distance of this star, this yields a physical size of about 11 times the Solar radius, radius of the Sun. The expanded stellar atmosphere, oute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apus
Apus is a small constellation in the Southern Celestial Hemisphere, southern sky. It represents a bird-of-paradise, and its name means "without feet" in Greek language, Greek because the bird-of-paradise was once wrongly believed to lack feet. First depicted on a celestial globe by Petrus Plancius in 1598, it was charted on a star atlas by Johann Bayer in his 1603 ''Uranometria''. The French explorer and astronomer Nicolas Louis de Lacaille charted and gave the brighter stars their Bayer designations in 1756. The five brightest stars are all reddish in hue. Shading the others at apparent magnitude 3.8 is Alpha Apodis, an orange giant that has around 48 times the diameter and 928 times the luminosity of the Sun. Marginally fainter is Gamma Apodis, another aging giant star. Delta Apodis is a double star, the two components of which are 103 Minute and second of arc, arcseconds apart and visible with the naked eye. Two star systems have been found to have exoplanet, planets. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Atmosphere
The stellar atmosphere is the outer region of the volume of a star, lying above the stellar core, radiation zone and convection zone. Overview The stellar atmosphere is divided into several regions of distinct character: * The photosphere, which is the atmosphere's lowest and coolest layer, is normally its only visible part. Light escaping from the surface of the star stems from this region and passes through the higher layers. The Sun's photosphere has a temperature in the range. Starspots, cool regions of disrupted magnetic field, lie in the photosphere. * Above the photosphere lies the chromosphere. This part of the atmosphere first cools down and then starts to heat up to about 10 times the temperature of the photosphere. * Above the chromosphere lies the transition region, where the temperature increases rapidly on a distance of only around . * Additionally, many stars have a molecular layer (MOLsphere) above the photosphere and just beyond or even within the chromosphe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Astronomical Union
The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. It was founded on 28 July 1919 in Brussels, Belgium and is based in Paris, France. The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. the Union had 85 national members and 12,734 individual members, spanning 90 countries and territories. Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epsilon Apodis
Epsilon Apodis is a star in the southern circumpolar constellation of Apus. Its identifier is a Bayer designation that is Latinized from ε Apodis, and abbreviated Eps Aps or ε Aps, respectively. This star has an apparent visual magnitude of 5.06, which is bright enough to be viewed from dark suburban skies. Based upon parallax measurements, it is at a distance of roughly from Earth. The star is drifting further away with a heliocentric radial velocity of +4.5 km/s. Based upon a stellar classification of B3 V, this is a massive, B-type main sequence star that is generating energy through the fusion of hydrogen at its core. Epsilon Apodis has more than six times the mass of the Sun and over four times the Sun's radius. It is radiating 1,614 times as much luminosity as the Sun from its photosphere at an effective temperature of 17,100 K. At this heat, it has a blue-white glow that is a characteristic of B-type stars. Epsilon Apodis is spinning rapidly, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Apodis
Alpha Apodis, also named Paradys, is the brightest star in the southern circumpolar constellation of Apus (constellation), Apus. It had the Greek alpha designation as part of the constellation which Johann Bayer called Apis Indica in his 1603 ''Uranometria'' star atlas. This identifier is a Bayer designation that is Romanization of Greek, Latinied from α Apodis, and abbreviated Alpha Aps or α Aps, respectively. The star has an apparent visual magnitude of approximately 3.825, which can be viewed with the naked eye. With a declination of –79°, this is a circumpolar star for much of the southern hemisphere. It can be identified on the night sky by drawing an imaginary line through Alpha Centauri and Alpha Circini then extending it toward the south celestial pole. This is a giant star with a stellar classification of K3IIICN0.5, indicating that this star has consumed the hydrogen at its core and has stellar evolution, evolved away from the main seque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Apodis
Eta Apodis is a star in the southern circumpolar constellation Apus. Its identifier is a Bayer designation that is Latinized from η Apodis, and abbreviated Eta Aps or η Aps, respectively. Based upon parallax measurements from Gaia Data Release 3, it is from Earth. It is drifting closer with a heliocentric radial velocity of −9 km/s. With an apparent visual magnitude of +4.9, it can be viewed with the naked eye from the southern hemisphere. Properties This star has about 1.77 times the mass of the Sun and 2.13 times the Sun's radius. It is radiating 15.5 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 7,860 K. Eta Apodis is a young star with an age of about 250 million years, and is spinning with a projected rotational velocity of 17 km/s. The stellar classification of Eta Apodis shows this to be an Am star, which means the spectrum shows chemically peculiarities. In particular, it is an A2-type star showing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Apodis
Delta Apodis is a double star in the southern constellation of Apus. Its identifier is a Bayer designation that is Romanization of Greek, Latinized from δ Apodis, and abbreviated Del Aps or δ Aps, respectively. Based on stellar parallax, parallax measurements, the distance to δ Apodis is approximately 620 light years, while δ Apodis is found to be around 563 light years from Earth. They may form a common proper motion pair. The brighter star, δ Apodis, has an apparent magnitude that varies from +4.66 to +4.87. It is a red giant with a stellar classification of M5 IIIb, and is classified as a semiregular variable with pulsations of multiple periods of 68.0, 94.9 and 101.7 days. δ Apodis has an apparent magnitude of +5.27 and is an orange stellar classification, K-type giant star, giant with a class of K3 III. Both stars are bright enough to be seen with the naked eye under good observing conditions. The pair have an angular separation of 103.4 arcs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Octantis
δ Octantis, Latinised as Delta Octantis, has the distinction of being Saturn's southern pole star A pole star is a visible star that is approximately aligned with the axis of rotation of an astronomical body; that is, a star whose apparent position is close to one of the celestial poles. On Earth, a pole star would lie directly overhead when .... An orange giant of class K2III, it has 1.2 times the mass of the Sun and about 25 times the Sun's radius. This star is about 4.3 billion years old, which is similar to the age of the Sun. Naming In Chinese caused by adaptation of the European southern hemisphere constellations into the Chinese system, (), meaning '' Exotic Bird'', refers to an asterism consisting of δ Octantis, ζ Apodis, ι Apodis, β Apodis, γ Apodis, δ1 Apodis, η Apodis, α Apodis and ε Apodis. Consequently, δ Octantis itself is known as (, ). [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Apodis
Gamma Apodis is a star in the southern circumpolar constellation of Apus. Its identifier is a Bayer designation that is Latinized from γ Apodis, and is abbreviated Gam Aps or γ Aps, respectively. It is visible to the naked eye with an apparent visual magnitude of 3.86. From parallax measurements, the distance to this star can be estimated as . The star is receding with a heliocentric radial velocity of +5.7 km/s. A stellar classification of G9 III identifies Gamma Apodis as a giant star in the later stages of its evolution. This is a red clump giant, which means it is on the horizontal branch and is generating energy through core helium fusion. The star has 2.3 times the mass of the Sun and has expanded to 10.3 times the Sun's radius. It is 2.7 billion years old and is spinning with a 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iota Apodis
Iota Apodis is a binary star system in the southern circumpolar constellation of Apus. Its identifier is a Bayer designation that is Latinized from ι Apodis, and abbreviated Iot Aps or ι Aps, respectively. This system is a faint target at an apparent visual magnitude of 5.41, but still visible to the naked eye from suitably dark skies. The distance to this star can be gauged from parallax measurements, yielding an estimate of with a 6% margin of error. The system is drifting closer with a heliocentric radial velocity of −4.3 km/s. The dual nature of this system was announced by W. S. Finsen in 1960, who reported an angular separation of . Their orbit has an angular separation of 0.091 arcseconds with an estimated orbital period of 59.32 years and an eccentricity (ovalness) of 0.17. Both stars are B-type main sequence stars, which indicates they shine with a blue-white hue. The brighter component has a stellar classification of B9 V and an appa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Apodis
Zeta Apodis is a star in the southern constellation of Apus. Its identifier is a Bayer designation that is Latinized from ζ Apodis, and abbreviated Zet Aps or ζ Aps, respectively. The star has an apparent visual magnitude of +4.78, which is bright enough to allow it to be seen with the naked eye. The distance to this star is known from parallax measurements to be around . It is drifting further away with a heliocentric radial velocity of +11 km/s. The spectrum of Zeta Apodis matches a stellar classification of K2 III, with the luminosity class of III indicating it is an evolved giant star. Zeta Apodis has roughly 1.5 times the Sun's mass, and expanded to 18 times the size of the Sun. It radiates 126 times the luminosity of the Sun from its photosphere at an effective temperature of 4,486 K, giving it the orange-hued glow of a K-type star. Naming In Chinese caused by adaptation of the European southern hemisphere constellations into the Chinese system, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Constellations
Traditional Chinese astronomy has a system of dividing the celestial sphere into asterisms or constellations, known as "officials" ( Chinese ''xīng guān''). The Chinese asterisms are generally smaller than the constellations of Hellenistic tradition. The Song dynasty (13th-century) Suzhou planisphere shows a total of 283 asterisms, comprising a total of 1,565 individual stars. The asterisms are divided into four groups, the Twenty-Eight Mansions (, ''Èrshíbā Xiù'') along the ecliptic, and the Three Enclosures of the northern sky. The southern sky was added as a fifth group in the late Ming dynasty based on European star charts, comprising an additional 23 asterisms. The Three Enclosures (, ''Sān Yuán'') include the Purple Forbidden Enclosure, which is centered on the north celestial pole and includes those stars which could be seen year-round,Needham, J.Astronomy in Ancient and Medieval China. ''Philosophical Transactions of the Royal Society of London''. Ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
