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Historical Brightest Stars
The Solar System and all of the visible stars are in different orbits about the core of the Milky Way galaxy. Thus, their relative positions change over time, and for the nearer stars this movement can be measured. As a star moves toward or away from us, its apparent brightness changes. Sirius is currently the brightest star in Earth's night sky, but it has not always been so. Canopus has persistently been the brightest star over the ages; other stars appear brighter only during relatively temporary periods, during which they are passing the Solar System at a much closer distance than Canopus. Working out exactly which stars were or will be the brightest at any given point in the past or future is difficult since it requires precise 3D proper motions of large numbers of stars and precise distances. This information only started to become available with the 1997 ''Hipparcos'' satellite data release. Jocelyn Tomkin used this data to compile a list of brightest star in Earth's nigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravity, gravitationally bound system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The solar mass, vast majority (99.86%) of the system's mass is in the Sun, with most of the Jupiter mass, remaining mass contained in the planet Jupiter. The four inner Solar System, inner system planets—Mercury (planet), Mercury, Venus, Earth and Mars—are terrest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeta Sagittarii
Zeta Sagittarii (ζ Sagittarii, abbreviated Zeta Sgr, ζ Sgr) is a triple star system and the third-brightest star in the constellation of Sagittarius. Based upon parallax measurements, it is about from the Sun. The three components are designated Zeta Sagittarii A (officially named Ascella , the traditional name for the entire system) and B, themselves forming a binary pair, and a smaller companion star, C. Nomenclature ''ζ Sagittarii'' ( Latinised to ''Zeta Sagittarii'') is the system's Bayer designation. The designations of the two components as ''ζ Sagittarii A'', ''B'' and ''C'' derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). It bore the traditional name ''Ascella'', from a Late Latin word meaning ''armpit''. In the catalogue of stars in the ''Calendarium'' of Al Achsasi al Mouakket, this star was designated ''Thalath al Sadirah'', w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albireo
Albireo is a double star designated Beta Cygni (β Cygni, abbreviated Beta Cyg, β Cyg). The International Astronomical Union uses the name "Albireo" specifically for the brightest star in the system. Although designated ' beta', it is fainter than Gamma Cygni, Delta Cygni, and Epsilon Cygni and is the fifth-brightest point of light in the constellation of Cygnus. Appearing to the naked eye to be a single star of magnitude 3, viewing through even a low-magnification telescope resolves it into its two components. The brighter yellow star, itself a very close binary system, makes a striking colour contrast with its fainter blue companion. Nomenclature ''β Cygni'' ( Latinised to ''Beta Cygni'') is the system's Bayer designation. The brighter of the two components is designated ''β¹ Cygni'' or ''Beta Cygni A'' and the fainter ''β² Cygni'' or ''Beta Cygni B''. The system's traditional name ''Albireo'' is a result of misunderstanding and mistranslation. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omicron Herculis
Omicron Herculis, Latinized from o Herculis, is a star in the constellation Hercules. It used to be called Masym ("the wrist"), but this name was transferred to Lambda Herculis. Properties Omicron Herculis is a B9.5III star approximately 106 pc from the Earth. It has an apparent magnitude of 3.83. The star radiates with a bluish-white hue, and has a luminosity approximately 355 times as bright as the Sun. Omicron Herculis is 3.49 solar masses. Stellar evolutionary caclulations show that it has just left the main sequence. Omicron Herculis is an eruptive variable of the Gamma Cassiopeiae class, which are rapidly rotating B-class stars with mass outflow. It has a projected rotational velocity of 194 km/s. Some sources list Omicron Herculis as being both spectroscopic and an interferometric binary star with a separation of about 60 milliarcseconds, although the companion star has not been confirmed. Omicron Hercules is notable for residing close to the coord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NR Canis Majoris
NR Canis Majoris is a binary star system in the southern constellation of Canis Major, located to the east of Sirius and Gamma Canis Majoris near the constellation border with Puppis. It has a yellow-white hue and is dimly visible to the naked eye with a combined apparent visual magnitude that fluctuates around 5.60. It is located at a distance of approximately 297 light years from the Sun based on parallax. The system is drifting closer to the Sun with a radial velocity of −29 km/s, and in about three million years it is predicted to approach within . At that time, the star will become the brightest in the night sky, potentially reaching magnitude −0.88. The magnitude 5.66 primary component is an F-type main-sequence star with a stellar classification of F2V. It is a Delta Scuti variable that varies by a few hundredths of a magnitude over roughly 16 hours. The star is an estimated 1.5 billion years old. It has a high rate of spin with a projected rota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upsilon Librae
Upsilon Librae (υ Lib, υ Librae) is the Bayer designation for a double star in the zodiac constellation Libra. With an apparent visual magnitude of 3.628, it is visible to the naked eye. The distance to this star, based upon an annual parallax shift of 14.58, is around 224 light years. It has a magnitude 10.8 companion at an angular separation of 2.0 arc seconds along a position angle of 151°, as of 2002. The brighter component is an evolved K-type giant star with a stellar classification of K3 III. The measured angular diameter, after correction for limb darkening, is . At the estimated distance of the star, this yields a physical size of about 31.5 times the radius of the Sun. It has 1.67 times the mass of the Sun and radiates 309 times the solar luminosity from its outer atmosphere at an effective temperature of 4,135 K. The star is about three billion years old. In around 2.3 million years, Upsilon Librae will be the brightest star in the nigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Draconis
Gamma Draconis (γ Draconis, abbreviated Gamma Dra, γ Dra), formally named Eltanin , is a star in the northern constellation of Draco. Contrary to its gamma-designation (historically third-ranked), it is the brightest star in Draco at magnitude 2.2, outshining Beta Draconis by nearly half a magnitude and Alpha Draconis by over a magnitude. Gamma Draconis is at a distance of from the Sun, as determined by parallax measurements from the Hipparcos astrometry satellite. In 1728, while unsuccessfully attempting to measure the parallax of this star, the English astronomer James Bradley discovered the aberration of light resulting from the relative movement of the Earth. Bradley's discovery apparently confirmed Copernicus' theory that the Earth revolved around the Sun. In 1.5 million years, Gamma Draconis will pass within 28 light years of Earth. For a period, if its current absolute magnitude does not change, it will be the brightest star in the night sky, nearly as bright ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Scuti
Delta Scuti, Latinized from δ Scuti, is a variable star in the southern constellation Scutum. With an apparent visual magnitude that fluctuates around 4.72, it is the fifth-brightest star in this small and otherwise undistinguished constellation. Analysis of the parallax measurements place this star at a distance of about from Earth. It is drifting closer with a radial velocity of −45 km/s. In 1900, William W. Campbell and William H. Wright used the Mills spectrograph at the Lick Observatory to determine that this star has a variable radial velocity. The period of this variability as well as 0.2 magnitude changes in luminosity demonstrated in 1935 that the variability was intrinsic, rather than being the result of a spectroscopic binary. In 1938, a secondary period was discovered and a pulsation theory was proposed to model the variation. Since then, observation of Delta Scuti has shown that it pulsates in multiple discrete radial and non-radial modes. The st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Aurigae
Beta Aurigae (Latinized from β Aurigae, abbreviated Beta Aur, β Aur), officially named Menkalinan , is a binary star system in the northern constellation of Auriga. The combined apparent visual magnitude of the system is 1.9, making it the second-brightest member of the constellation after Capella. Using the parallax measurements made during the Hipparcos mission, the distance to this star system can be estimated as , give or take a half-light-year margin of error. In around one million years, Beta Aurigae will become the brightest star in the night sky. – based on computations from HIPPARCOS data. (The calculations exclude stars whose distance or proper motion is uncertain.) tp://tlgleonid.asuscomm.com/HITACHI/BOOK_ASTRO/S&T/SkyandTelescope_1998%20-%20astronomy/04/199804059063.pdf PDF/ref> Nomenclature ''β Aurigae'' is the star system's Bayer designation. The traditional name ''Menkalinan'' is derived from the Arabic منكب ذي العنان ''mankib ðī-l- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vega
Vega is the brightest star in the northern constellation of Lyra. It has the Bayer designation α Lyrae, which is Latinised to Alpha Lyrae and abbreviated Alpha Lyr or α Lyr. This star is relatively close at only from the Sun, and one of the most luminous stars in the Sun's neighborhood. It is the fifth-brightest star in the night sky, and the second-brightest star in the northern celestial hemisphere, after Arcturus. Vega has been extensively studied by astronomers, leading it to be termed "arguably the next most important star in the sky after the Sun". Vega was the northern pole star around 12,000 BCE and will be so again around the year 13,727, when its declination will be . Vega was the first star other than the Sun to have its image and spectrum photographed. It was one of the first stars whose distance was estimated through parallax measurements. Vega has functioned as the baseline for calibrating the photometric brightness scale and was one of the st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capella (star)
Capella is the brightest star in the northern constellation of Auriga. It has the Bayer designation α Aurigae, which is Latinised to Alpha Aurigae and abbreviated Alpha Aur or α Aur. Capella is the sixth-brightest star in the night sky, and the third-brightest in the northern celestial hemisphere after Arcturus and Vega. A prominent object in the northern winter sky, it is circumpolar to observers north of 44°N. Its name meaning "little goat" in Latin, Capella depicted the goat Amalthea that suckled Zeus in classical mythology. Capella is relatively close, at from the Sun. It is one of the brightest X-ray sources in the sky, thought to come primarily from the corona of Capella Aa. Although it appears to be a single star to the naked eye, Capella is actually a quadruple star system organized in two binary pairs, made up of the stars Capella Aa, Capella Ab, Capella H and Capella L. The primary pair, Capella Aa and Capella Ab, are two bright-yellow gia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldebaran
Aldebaran (Arabic: “The Follower”, "الدبران") is the brightest star in the zodiac constellation of Taurus. It has the Bayer designation α Tauri, which is Latinized to Alpha Tauri and abbreviated Alpha Tau or α Tau. Aldebaran varies in brightness from an apparent visual magnitude 0.75 down to 0.95, making it (typically) the fourteenth-brightest star in the night sky. It is located at a distance of approximately 65 light-years from the Sun. The star lies along the line of sight to the nearby Hyades cluster. Aldebaran is a giant star that is cooler than the Sun with a surface temperature of , but its radius is about 44 times the Sun's, so it is over 400 times as luminous. It spins slowly and takes 520 days to complete a rotation. Aldebaran is believed to host a planet several times the mass of Jupiter, named . The planetary exploration probe Pioneer 10 is heading in the general direction of the star and should make its closest approach in about two million ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
