Sunday, December 2, 2012

The Marquesas islanders called it Na-pai-ka; the Maoriconstellation Pipiri may correspond to modern Aries as well.[25] In indigenous Peruvian astronomy, a constellation with most of the same stars as Aries existed. It was called the "Market Moon" and the "Kneeling Terrace", as a reminder for when to hold the annual harvest festival, Ayri Huay. Sony VAIO VPCF23N1E Battery
Aries has three prominent stars forming an asterism, designated Alpha, Beta, and Gamma Arietis by Johann Bayer. All three are commonly used for navigation.[26] There is also one other star above the fourth magnitude, 41 Arietis. α Arietis, called Hamal, is the brightest star in Aries. Sony VAIO VPCY21S1E/L Battery
Its traditional name is derived from the Arabic word for "lamb" or "head of the ram" (ras al-hamal), which references Aries's mythological background.[17] With a spectral class of K2[12] and a luminosity class of III, it is an orange giant with an apparent visual magnitude of 2.00, which lies 66light-years from Earth. Sony VAIO VPCY21S1E/G battery
Hamal has a luminosity of 96 L and its absolute magnitude is −0.1.[28]
β Arietis, also known as Sheratan, is a blue-white star with an apparent visual magnitude of 2.64. Its traditional name is derived from "sharatayn", the Arabic word for "the two signs", referring to both Beta and Gamma Arietis in their position as heralds of the vernal equinox. Sony VAIO VPCF24M1E battery
The two stars were known to the Bedouin as "qarna al-hamal", "horns of the ram".[29] It is 59 light-years from Earth. It has a luminosity of 11 L and its absolute magnitude is 2.1.[28] It is a spectroscopic binary star, one in which the companion star is only known through analysis of the spectra. Sony VAIO VGN-NW21EF/S Battery
The spectral class of the primary is A5.[12] Hermann Carl Vogel determined that Sheratan was a spectroscopic binary in 1903; its orbit was determined by Hans Ludendorff in 1907. It has since been studied for its eccentric orbit.[31]
γ Arietis, with a common name of Mesartim, is a binary star with two white-hued components, located in a rich field of magnitude 8–12 stars. Sony VAIO VGN-NW21JF Battery
Its traditional name has conflicting derivations. It may be derived from a corruption of "al-sharatan", the Arabic word meaning "pair" or a word for "fat ram".However, it may also come from the Sanskrit for "first star of Aries" or the Hebrew for "ministerial servants", both of which are unusual languages of origin for star names. Sony VAIO VGN-NW21MF Battery
Along with Beta Arietis, it was known to the Bedouin as "qarna al-hamal".[29] The primary is of magnitude 4.59 and the secondary is of magnitude 4.68.[28] The system is 164 light-years from Earth.[33] The two components are separated by 7.8 arcseconds,[2] and the system as a whole has an apparent magnitude of 3.9. Sony VAIO VGN-NW21MF/W Battery
The primary has a luminosity of 60 L and the secondary has a luminosity of 56 L; the primary is an A-type star with an absolute magnitude of 0.2 and the secondary is a B9-type star with an absolute magnitude of 0.4.[28] The angle between the two components is 1°. Sony VAIO VGN-NW21ZF Battery
Mesartim was discovered to be a double star byRobert Hooke in 1664, one of the earliest such telescopic discoveries. The primary, γ1 Arietis, is an Alpha² Canum Venaticorum variable star that has a range of 0.02 magnitudes and a period of 2.607 days. It is unusual because of its strong silicon emission lines.[31] Sony VAIO VGN-NW31EF/W Battery
The constellation is home to several double stars, including Epsilon, Lambda, and Pi Arietis. ε Arietis is a binary star with two white components. The primary is of magnitude 5.2 and the secondary is of magnitude 5.5. The system is 290 light-years from Earth.[11] Its overall magnitude is 4.63, and the primary has an absolute magnitude of 1.4. Sony VAIO VGN-NW31JF Battery
Its spectral class is A2. The two components are separated by 1.5 arcseconds.[28] λ Arietis is a wide double star with a white-hued primary and a yellow-hued secondary. The primary is of magnitude 4.8 and the secondary is of magnitude 7.3.[11] The primary is 129 light-years from Earth. Sony VAIO VGN-NW320F/B Battery
It has an absolute magnitude of 1.7 and a spectral class of F0.[28] The two components are separated by 36 arcseconds at an angle of 50°; the two stars are located 0.5° east of 7 Arietis.[2] π Arietis is a close binary star with a blue-white primary and a white secondary. The primary is of magnitude 5.3 and the secondary is of magnitude 8.5.[11] Sony VAIO VGN-NW320F/TC Battery
The primary is 776 light-years from Earth.[35] The primary itself is a wide double star with a separation of 25.2 arcseconds; the tertiary has a magnitude of 10.8. The primary and secondary are separated by 3.2 arcseconds.[28]
Most of the other stars in Aries visible to the naked eye have magnitudes between 3 and 5. δ Ari, Sony VAIO VGN-NW35E Battery
called Boteïn, is a star of magnitude 4.35, 170 light-years away. It has an absolute magnitude of −0.1 and a spectral class of K2.[28][36] ζ Arietis is a star of magnitude 4.89, 263 light-years away. Its spectral class is A0 and its absolute magnitude is 0.0.[28][37] 14 Arietis is a star of magnitude 4.98, 288 light-years away. Sony VAIO VGN-NW380F/S Battery
Its spectral class is F2 and its absolute magnitude is 0.6.[28][38] 39 Arietis is a similar star of magnitude 4.51, 172 light-years away. Its spectral class is K1 and its absolute magnitude is 0.0. 35 Arietis is a dim star of magnitude 4.55, 343 light-years away. Its spectral class is B3 and its absolute magnitude is −1.7. Sony VAIO VGN-NW380F/T Battery
41 Arietis, known both as c Arietis and Nair al Butain, is a brighter star of magnitude 3.63, 165 light-years away. Its spectral class is B8 and it has a luminosity of 105 L. Its absolute magnitude is −0.2. 53 Arietis is a runaway star of magnitude 6.09, 815 light-years away. Its spectral class is B2. Sony VAIO VGN-NW50JB Battery
It was likely ejected from the Orion Nebula approximately five million years ago, possibly due to supernovae.[31] Finally, Teegarden's Star is the closest star to Earth in Aries. It is a brown dwarf of magnitude 15.14 and spectral class M6.5V. With a proper motion of 5.1 arcseconds per year, it is the 24th closest star to Earth overall.[3] Sony VAIO VGN-NW51FB/N Battery
Aries has its share of variable stars, including R and U Arietis, Mira-type variable stars, and T Arietis, a semi-regular variable star. R Arietis is a Mira variable star that ranges in magnitude from a minimum of 13.7 to a maximum of 7.4 with a period of 186.8 days.[28] It is 4,080 light-years away. Sony VAIO VGN-NW51FB/W Battery
U Arietis is another Mira variable star that ranges in magnitude from a minimum of 15.2 to a maximum of 7.2 with a period of 371.1 days.[28] T Arietis is a semiregular variable star that ranges in magnitude from a minimum of 11.3 to a maximum of 7.5 with a period of 317 days.[28] It is 1,630 light-years away. Sony VAIO VGN-NW70JB Battery
One particularly interesting variable in Aries is SX Arietis, a rotating variable star considered to be the prototype of its class, helium variable stars. SX Arietis stars have very prominent emission lines of Helium I and Silicon III. They are normally main-sequence B0p—B9p stars, and their variations are not usually visible to the naked eye. Sony VAIO VGN-NW71FB/N Battery
Therefore, they are observed photometrically, usually having periods that fit in the course of one night. Similar to Alpha² Canum Venaticorum variables, SX Arietis stars have periodic changes in their light and magnetic field, which correspond to the periodic rotation; they differ from the Alpha² Canum Venaticorum variables in their higher temperature. Sony VAIO VGN-NW71FB/W Battery
There are between 39 and 49 SX Arietis variable stars currently known; ten are noted as being "uncertain" in the General Catalog of Variable Stars.
The few deep-sky objects in Aries are very dim. Nevertheless, several scientifically interesting galaxies lie within its borders; it has spiral, elliptical, andinteracting galaxies. Sony VAIO VGN-NW91FS Battery
NGC 772 is a spiral galaxy with an integrated magnitude of 10.3, located southeast of β Arietis and 15 arcminutes west of 15 Arietis.[12] It is a relatively bright galaxy and shows obvious nebulosity and ellipticity in an amateur telescope. It is 7.2 by 4.2 arcminutes, meaning that its surface brightness, magnitude 13.6, is significantly lower than its integrated magnitude.Sony VAIO VGN-NW91GS Battery
NGC 772 is a class SA(s)b galaxy, which means that it is an unbarred spiral galaxy without a ring that possesses a somewhat prominent bulge and spiral arms that are wound somewhat tightly. The main arm, on the northwest side of the galaxy, is home to many star forming regions; this is due to previous gravitational interactions with other galaxies. Sony VAIO VGN-NW91VS Battery
NGC 772 has a small companion galaxy, NGC 770, that is about 113,000 light-years away from the larger galaxy. The two galaxies together are also classified as Arp 78 in the Arp peculiar galaxy catalog. NGC 772 has a diameter of 240,000 light-years and the system is 114 million light-years from Earth. Sony VAIO VGN-SR11M Battery
Another spiral galaxy in Aries is NGC 673, a face-on class SAB(s)c galaxy. It is a weakly barred spiral galaxy with loosely wound arms. It has no ring and a faint bulge and is 2.5 by 1.9 arcminutes. It has two primary arms with fragments located farther from the core. 171,000 light-years in diameter, NGC 673 is 235 million light-years from Earth. Sony VAIO VGN-SR11MR Battery
NGC 678 and NGC 680 are a pair of galaxies in Aries that are only about 200,000 light-years apart. Part of the NGC 691 group of galaxies, both are at a distance of approximately 130 million light-years. NGC 678 is an edge-on spiral galaxy that is 4.5 by 0.8 arcminutes. Sony VAIO VGN-SR140D Battery
NGC 680, an elliptical galaxy with an asymmetrical boundary, is the brighter of the two at magnitude 12.9; NGC 678 has a magnitude of 13.35. Both galaxies have bright cores, but NGC 678 is the larger galaxy at a diameter of 171,000 light-years; NGC 680 has a diameter of 72,000 light-years. NGC 678 is further distinguished by its prominent dust lane. Sony VAIO VGN-SR140D/B Battery
NGC 691 itself is a spiral galaxy slightly inclined to our line of sight. It has multiple spiral arms and a bright core. Because it is so diffuse, it has a low surface brightness. It has a diameter of 126,000 light-years and is 124 million light-years away.[46] NGC 877 is the brightest member of an 8-galaxy group that also includes NGC 870, Sony VAIO VGN-SR140D/P Battery
NGC 871, and NGC 876, with a magnitude of 12.53. It is 2.4 by 1.8 arcminutes and is 178 million light-years away with a diameter of 124,000 light-years. Its companion is NGC 876, which is about 103,000 light-years from the core of NGC 877. They are interacting gravitationally, as they are connected by a faint stream of gas and dust. Sony VAIO VGN-SR140D/S Battery
Arp 276 is a different pair of interacting galaxies in Aries, consisting of NGC 935 and IC 1801.NGC 821 is an E6 elliptical galaxy. It is unusual because it has hints of an early spiral structure, which is normally only found in lenticular and spiral galaxies. NGC 821 is 2.6 by 2.0 arcminutes and has a visual magnitude of 11.3. Sony VAIO VGN-SR140E Battery
Its diameter is 61,000 light-years and it is 80 million light-years away.[46]Another unusual galaxy in Aries is Segue 2. Segue 2 is a dwarf galaxy that is a satellite galaxy of the Milky Way, recently discovered to be a potential relic of the epoch of reionization.
Aries is home to several meteor showers. Sony VAIO VGN-SR140E/B Battery
The Daytime Arietid meteor shower is one of the strongest meteor showers that occurs during the day, lasting from 22 May to 2 June. It is an annual shower associated with the Marsden group of comets that peaks on 7 June with a maximum zenithal hourly rate of 54 meteors.[49][50]Its parent body may be the asteroid Icarus. Sony VAIO VGN-SR140E/P Battery
The meteors are sometimes visible before dawn, because the radiant is 32 degrees away from the Sun. They usually appear at a rate of 1–2 per hour as "earthgrazers", meteors that last several seconds and often begin at the horizon. Because most of the Daytime Arietids are not visible to the naked eye, they are observed in the radio spectrum. Sony VAIO VGN-SR140E/S Battery
This is possible because of the ionized gas they leave in their wake.[51][52] Other meteor showers radiate from Aries during the day; these include the Daytime Epsilon Arietids and the Northern and Southern Daytime May Arietids.[53] The Jodrell Bank Observatory discovered the Daytime Arietids in 1947 when James Hey and G.S. Sony VAIO VGN-SR140N/S Battery
Stewart adapted the World War II-era radar systems for meteor observations.[52]
The Delta Arietids are another meteor shower radiating from Aries. Peaking on 9 December with a low peak rate, the shower lasts from 8 December to 14 January, with the highest rates visible from 8 to 14 December. Sony VAIO VGN-SR165E/B Battery
The average Delta Aquarid meteor is very slow, with an average velocity of 13.2 kilometres (8.2 mi) per second. However, this shower sometimes produces bright fireballs.[54] This meteor shower has northern and southern components, both of which are likely associated with 1990 HA, a near-earth asteroid.[55] Sony VAIO VGN-SR165E/P Battery
The Autumn Arietids also radiate from Aries. The shower lasts from 7 September to 27 October and peaks on 9 October. Its peak rate is low.[56] The Epsilon Arietids appear from 12 to 23 October.[7] Other meteor showers radiating from Aries include the October Delta Arietids, Daytime Epsilon Arietids, Daytime May Arietids, Sony VAIO VGN-SR165E/S Battery
Sigma Arietids, Nu Arietids, and Beta Arietids.[53] The Sigma Arietids, a class IV meteor shower, are visible from 12 to 19 October, with a maximum zenithal hourly rate of less than two meteors per hour on 19 October.
Aries contains several stars with extrasolar planets. Sony VAIO VGN-SR190EBJ Battery
HIP 14810, a G5 type star, is orbited by three giant planets (those more than ten times the mass of Earth).[58] HD 12661, like HIP 14810, is a G-type main sequence star, slightly larger than the Sun, with two orbiting planets. One planet is 2.3 times the mass of Jupiter, and the other is 1.57 times the mass of Jupiter. Sony VAIO VGN-SR190EBQ Battery
HD 20367 is a G0 type star, approximately the size of the Sun, with one orbiting planet. The planet, discovered in 2002, has a mass 1.07 times that of Jupiter and orbits every 500 days.
Taurus is one of the constellations of the zodiac, which means it is crossed by the plane of the ecliptic. Sony VAIO VGN-SR190EEJ/C Battery
Its name is aLatin word meaning "bull", and its astrological symbol is a stylized bull's head:   (Unicode ♉). Taurus is a large and prominent constellation in the northern hemisphere's winter sky. It is one of the oldest constellations, dating back to at least the Early Bronze Age when it marked the location of the Sun during the spring equinox. Sony VAIO VGN-SR190NAB Battery
Taurus came to symbolize the bull in the mythologies of Ancient Babylon, Egypt and Greece.
There are a number of features of interest to astronomers. Taurus hosts two of the nearest open clusters to Earth, thePleiades and the Hyades, both of which are visible to the naked eye. Sony VAIO VGN-SR190NBB Battery
At first magnitude, the red giant Aldebaran is the brightest star in the constellation. In the northwest part of Taurus is the supernova remnant Messier 1, more commonly known as the Crab Nebula. One of the closest regions of active star location, the Taurus-Auriga complex, crosses into the northern part of the constellation. Sony VAIO VGN-SR190NDB Battery
The variable star T Tauri is the prototype of a class of pre-main-sequence stars.
Taurus is a large and prominent constellation in the northern hemisphere's winter sky, between Aries to the west andGemini to the east; to the north lie Perseus and Auriga, to the southeast Orion, to the south Eridanus, and to the southwest Cetus. Sony VAIO VGN-SR190NEB Battery
In September and October, Taurus is visible in the evening along the eastern horizon. The most favorable time to observe Taurus in the night sky is during the months of December and January. By March and April, the constellation will appear to the west during the evening twilight.[5] Sony VAIO VGN-SR190NGB Battery
This constellation forms part of the zodiac, and hence is intersected by the ecliptic. This circle across the celestial sphere forms the apparent path of the Sun as the Earth completes its annual orbit. As the orbital plane of the Moon and the planets lie near the ecliptic, they can usually be found in the constellation Taurus during some part of each year. Sony VAIO VGN-SR190PAB Battery
The galactic plane of the Milky Way intersects the northeast corner of the constellation and the galactic anticenter is located near the border between Taurus and Auriga. Taurus is the only constellation crossed by all three of the galactic equator, celestial equator, and ecliptic. A ring-like galactic structure known as the Gould's Belt passes through the Taurus constellation. Sony VAIO VGN-SR190PCB Battery
The recommended three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is "Tau".[2] The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 26 segments. In the equatorial coordinate system, Sony VAIO VGN-SR190PFB Battery
the right ascension coordinates of these borders lie between 03h 23.4mand 05h 53.3m, while the declination coordinates are between 31.10° and −1.35°.[7] Because a small part of the constellation lies to the south of the celestial equator, this can not be a completely circumpolar constellation at any latitude. Sony VAIO VGN-SR19VN Battery
During November, the Taurid meteor shower appears to radiate from the general direction of this constellation. The Beta Taurid meteor shower occurs during the months of June and July in the daytime, and is normally observed using radio techniques. In October, between the 18th and the 29th, both the Northern Taurids and the Southern Taurids are active; Sony VAIO VGN-SR19VN Battery
though the latter stream is stronger.[11] However, between November 1 and 10, the two streams equalize.The brightest member of this constellation is Aldebaran, an orange-hued,spectral class K5 III giant star.[13] Its name is from الدبران al-dabarān, Arabicfor "the follower" (of the Pleiades). Sony VAIO VGN-SR19VRN Battery
Forming the profile of a Bull's face is a V or A-shaped asterism of stars. This outline is created by prominent members of the Hyades,[16] the nearest distinct open star cluster after the Ursa Major Moving Group.[17] In this profile, Aldebaran forms the bull's bloodshot eye, which has been described as "glaring menacingly at the hunter Orion",Sony VAIO VGN-SR19XN Battery
a constellation that lies just to the southwest. The Hyades span about 5° of the sky, so that they can only be viewed in their entirety with binoculars or the unaided eye.[19] It includes a naked eye double star, Theta Tauri, with a separation of 5.6 arcminutes.[20]
In the northeastern quadrant of the Taurus constellation lie the Pleiades (M45), Sony VAIO VGN-SR19XN Battery
one of the best known open clusters, easily visible to the naked eye. The seven most prominent stars in this cluster are at least visual magnitude six, and so the cluster is also named the "Seven Sisters". However, many more stars are visible with even a modest telescope. Sony VAIO VGN-SR210J/S Battery
The name of the star Aldebaran most likely comes from the fact that it follows the Pleiades during the nightly motion of the celestial sphere across the sky.[14] Astronomers estimate that the cluster has approximately 500-1,000 stars, all of which are around 100 million years old. However, they vary considerably in type. Sony VAIO VGN-SR21M/S Battery
The Pleiades themselves are represented by large, bright stars; there are also many small brown dwarfs and white dwarfs. The cluster is estimated to dissipate in another 250 million years. The Pleiades cluster is classified as a Shapley class c and Trumpler class I 3 r n cluster, indicating that it is irregularly shaped and loose, though concentrated at its center and detached from the star field. Sony VAIO VGN-SR21RM/H Battery
In the northern part of the constellation to the northwest of the Pleiades lies the Crystal Ball Nebula, known by its catalogue designation of NGC 1514. Thisplanetary nebula is of historical interest following its discovery by German-born English astronomer William Herschel in 1790. Prior to that time, Sony VAIO VGN-SR21RM/S Battery
astronomers had assumed that nebulae were simply unresolved groups of stars. However, Herschel could clearly resolve a star at the center of the nebula that was surrounded by a nebulous cloud of some type. In 1864, English astronomer William Huggins used the spectrum of this nebula to deduce that the nebula is a luminous gas, rather than stars. Sony VAIO VGN-SR220J/B Battery
To the west, the two horns of the bull are formed by Beta (β) Tauri and Zeta (ζ) Tauri; two star systems that are separated by 8°. Beta is a white, spectral class B7 III giant star known as El Nath, which comes from the Arabic phrase "the butting", as in butting by the horns of the bull. Sony VAIO VGN-SR220J/H Battery
It is the second brightest star in the constellation, and shares the border with the neighboring constellation of Auriga. As a result, it also bears the designation Gamma Aurigae. Zeta Tauri is an eclipsing binary star that completes an orbit every 133 days.
A degree to the northwest of ζ Tauri is the Crab Nebula (M1), a supernova remnant. Sony VAIO VGN-SR240J/B Battery
This expanding nebula was created by a Type II supernova explosion, which was seen from Earth on July 4, 1054. It was bright enough to be observed during the day, and is mentioned in Chinese historical texts. At its peak the supernova reached magnitude −4, but the nebula is currently magnitude 8.4 and requires a telescope to observe. Sony VAIO VGN-SR240N/B Battery
North American peoples also observed the supernova, as evidenced from a painting on a New Mexican canyon and various pieces of pottery that depict the event. However, the remnant itself was not discovered until 1731, when John Bevis found it.[22]
The star Lambda (λ) Tauri is an eclipsing binary star. Sony VAIO VGN-SR290JTH Battery

No comments:

Post a Comment