Turkey (constellation)

Pavo is a constellation in the Southern Hemisphere. The constellation was one of twenty constellations created by Pieter Dirkszoon Keyser and Frederick de Houtman between 1595 and 1597, and first appeared in Johann Bayer's 1603 book Uranometria.

History and mythology

History of the modern constellation.

Pavo was one of twelve constellations established by Petrus Plancius from observations of the southern sky by explorers Pieter Dirkszoon Keyser and Frederick de Houtman, who had sailed on the first Dutch trading expedition, known as the Eerste Schipvaart, to the East Indies. It first appeared on a 35 cm (14 in) diameter celestial globe published in 1598 in Amsterdam by Plancius with Jodocus Hondius. The first representation of this constellation in a celestial atlas was in German cartographer Johann Bayer's Uranometria of 1603. De Houtman included it in his catalog of southern stars the same year under the Dutch name De Pauww, "The Peacock" 34;. Pavo and the nearby constellations Phoenix, Grus, and Tucana are collectively called "Birds of the South"

The peacock in Greek mythology.

According to Mark Chartrand, former executive director of the National Space Institute, Plancius might not have been the first to designate this group of stars as a peacock: "In Greek myth, the stars that are now the peacock royal were Argos or Argus, builder of the ship Argo. The goddess Juno transformed him into a peacock and placed him in the sky along with her ship "Indeed, the peacock" it symbolized the starry firmament "to the Greeks, and the goddess Hera was believed to drive through the heavens in a chariot drawn by peacocks.

The peacock and the nomenclature "Argus" they are also prominent in a different myth, in which Io, a beautiful princess of Argos, was coveted by Zeus (Jupiter). Zeus turned Io into a heifer to deceive her wife (and her sister) from her Hera from her and a mate with her. Hera saw through Zeus's scheme and asked for her heifer as a gift from her. Zeus, unable to refuse such a reasonable request, reluctantly gave the heifer to Hera, who promptly banished Io and arranged for Argus Panoptes, a creature with a hundred eyes, to protect the now-pregnant Ius from Zeus. Meanwhile, Zeus begged Hermes to save Io; Hermes used the music to lull Argus Panoptes to sleep, then killed him. Hera adorned the tail of a peacock, her favorite bird, with the eyes of Argus in her honor.

As recounted in Ovid's Metamorphoses, the death of Argus Panoptes also contains an explicit celestial reference: 'Argus lay dead; so many eyes, so bright, dull, and all a hundred wrapped up in one night. Saturnia [Hera] recovered those eyes to place them in her place among the feathers of her bird [the peacock, Pavo] and filled her tail with starry jewels."

It is uncertain whether Dutch astronomers had Greek myths in mind when creating Pavo but, according to other constellations introduced by Plancius via Keyser and De Houtmann, the "peacock" in the new constellation it probably refers to the green peacock, which explorers would have found in the East Indies, rather than the blue peacock known to the ancient Greeks.

Equivalents in other cultures.

The people of Guardamar in the Northern Territory of Australia saw the stars of Pavo and the neighboring constellation of Ara as flying foxes.

Features

Stars

Although it represented Pavo in its charter, Bayer did not assign its stars Bayer designations. The French explorer and astronomer Nicolas-Louis de Lacaille labeled them from Alpha to Omega in 1756, but omitted Psi and Xi, labeling two pairs of stars very close to Mu and Phi Pavonis. In 1879, American astronomer Benjamin Gould designated a star Xi Pavonis when he felt its brightness warranted a name, but dropped Chi Pavonis due to its weakness.

Near the constellation's northern border with Telescopium is Alpha Pavonis, Pavo's brightest star. Its proper name, Peacock, is an English translation of the name of the constellation. It was assigned by the British Majesty's Office of the Nautical Almanac in the late 1930s; the Royal Air Force insisted that all bright stars must have names, as until now the star lacked a proper name. Alpha has an apparent (or visual) magnitude of 1.91 and a spectral type B2IV. It is a spectroscopic binary system, an estimate that places the distance between the pair of stars as 0.21 astronomical units (AU), or half the distance between Mercury and the Sun. The two stars revolve around each other in just 11 days and 18 hours. The star system is located about 180 light years from Earth.

With an apparent magnitude of 3.43, Beta Pavonis is the second brightest star in the constellation. A white giant of the spectral class A7III, it is an aging star that has exhausted the hydrogen fuel in its core and has expanded and cooled after leaving the main sequence. It is located 135 light years from the Solar System.

A few degrees west of Beta is Delta Pavonis, a nearby Sun-like but more evolved star; this is a yellow subgiant of spectral type G8IV and apparent magnitude 3.56 that is only 19.9 light years distant from Earth. To the east of Beta and on the constellation's eastern border with the Indus is Gamma Pavonis, a fainter solar-type star 30 light-years from Earth with a magnitude of 4.22 and stellar class F9V. Other nearby stars in Pavo are much fainter: SCR 1845-6357 (the closest star in Pavo) is a binary system with an apparent magnitude of 17.4 consisting of a red dwarf and a brown dwarf lying at a distance of 12.6 light-years, while Gliese 693 is a red dwarf of magnitude 10.78 located 19 light-years away.

Pavo contains several variable stars of note. Lambda Pavonis is a brilliant bright variable ranging between magnitudes 3.4 and 4.4; this variation can be observed with the naked eye. Classified as a Gamma Cassiopeiae variable or shell star, it is of spectral type B2II-IIIe and is located about 1430 light years distant from Earth. Kappa Pavonis is a variable of W Virginis, a subclass of the Type II Cepheid. Its range varies from 3.91 to 4.78 over 9 days and it is a yellow-white supergiant that pulsates between the spectral classes F5I-II and G5I-II. NU and V Pavonis are pulsating semiregular red red giant stars. NU has a spectral type M6III and ranges from magnitude 4.9 to 5.3, while V Pavonis ranges from magnitude 6.3 to 8.2 over two periods of 225.4 and 3735 days simultaneously. V is a carbon star of spectral type C6.4 (Nb) with a prominent red hue.

Located in the west of the constellation and representing the peacock's tail are Eta and Xi Pavonis. At apparent magnitude 3.6, Eta is a luminous orange giant of spectral type K2II about 350 light-years from Earth. Xi Pavonis is a multiple star system visible in small telescopes as a brighter orange star and a fainter white companion. Located about 470 light-years from Earth, the system has a magnitude of 4.38. AR Pavonis is a faint but well-studied eclipsing binary composed of a hotter red giant star about 18,000 light-years from Earth. It has some characteristics of a cataclysmic variable, the smallest component likely to have an accretion disk. The visual magnitude ranges from 7.4 to 13.6 over 605 days.

Sun Twin

The star HD 186302 located eb RA 19h 38 '24 ″ Dec -70 ° 26 ′ 0 ″ mag 8.4, resides within Pavo at a distance of approximately 184 light-years from the solar system. As of November 2018, HD186302 is only the second star identified as a solar sister, this one is particularly similar to the Sun, same G2 spectrum, virtually the same mass, with a double spectrum revealing identical metallicity.

The first star identified as a solar sister in May 2014, HD 162826, within Hercules is an F-type main sequence star somewhat more powerful than the Sun, with a mass 15% greater.

Planetary systems and debris disks.

Six stars with planetary systems have been found. Three planets have been discovered in the orange star HD 181433 system, an inner super-Earth with an orbital period of 9.4 days and two outer gas giants with periods of 2.6 and 6 years respectively. HD 196050 and HD 175167 are yellow G-class Sun-like stars, while HD 190984 is an F-class main sequence star slightly larger and hotter than the Sun; all three are accompanied by a gas giant companion. HD 172555 is a young white A-type main-sequence star whose two planets appear to have had a major collision within the last few thousand years. Spectrographic evidence for large amounts of silicon dioxide gas indicates that the smaller of the two, which was at least the size of Earth's moon, was destroyed, and the larger, which was at least the size of Mercury., was badly damaged. Evidence of the collision was detected by NASA's Spitzer Space Telescope. In the south of the constellation, Epsilon Pavonis is a magnitude 3.95 white main-sequence star of spectral type A0Va located about 105 light-years from Earth. It appears to be surrounded by a narrow dust ring at a distance of 107 AU.

Deep Sky Objects

Deep sky objects in Pavo include NGC 6752, the third brightest globular cluster in the sky, after 47 Tucanae and Omega Centauri. An estimated 100 light-years across, it contains 100,000 stars. Three degrees to the south is NGC 6744, a spiral galaxy about 30 million light-years from Earth that resembles the Milky Way but is twice its diameter. A type 1c supernova was discovered in the galaxy in 2005; known as SN2005at, it peaked at magnitude 16.8 The dwarf galaxy IC 4662 lies 10 arc minutes northeast of Eta Pavonis, and has a magnitude of 11.62. Located just 8 million light-years away, it has several regions of high star formation. The 14th magnitude galaxy IC 4965 lies 1.7 degrees west of Alpha Pavonis, and is a central member of the Shapley Supercluster.

Meteor Showers

Pavo is the radiant of two annual meteor showers: the Delta Pavonids and the August Pavonids. Appearing from March 21 to April 8 and generally reaching April 5 and 6, Delta Pavonids is thought to be associated with comet Grigg-Mellish. The shower was discovered by Michael Buhagiar of Perth, Australia, who observed meteors six times between 1969 and 1980. The August peaks peak around August 31 and are thought to be associated with the Halley-type Comet Levy (P / 1991 L3).

Stars

Main Stars

• α Pavonis (Peacock), the brightest star of the constellation with magnitude +1.94, is a blue-colored binary star to 183 light years away.
• β Pavonis, white star of magnitude 3.43.
• γ Pavonis, yellow dwarf of magnitude 4,21 to 30 light years of the solar system. Something warmer and significantly older than the Sun is one of the priority objectives within the search for Earth planets.
• δ Pavonis, of magnitude 3.55, yellow star of the main or subgigant sequence only 20 light years away.
• ε Pavonis, white star of the main sequence of magnitude 3.95.
• ι Pavonis, yellow dwarf located 58 light years away.
• κ Pavonis, variable star W Virginis, whose brightness varies between magnitude 3,91 and 4.78.
• π Pavonis, peculiar star of magnitude 4.33.
• φ Pavonis, denomination that encompasses two different stars: φ1 Pavonis, star of magnitude 4.8 surrounded by a circumestelar disc of dust, and φ2 Pavonis, yellow dwarf with an unconfirmed planet orbiting.
• X Pavonis, red giant and semi-regular variable.
• HD 172555, white star where you think two planetesimales collided at high speed.
• HD 181433, orange dwarf with an extrasolar planet "supertier" and a Jordanian planet.
• HD 189567, solar analog of magnitude 6.07.
• SCR 1845-6357, system formed by a red dwarf and a brown dwarf at 12.57 light years away from the solar system.
• Gliese 693, red dwarf 19 light years away.
• PSR B1906-59, a binary pulp whose companion is a white dwarf.

Other stars with Bayer designation

• γ Pav 4.01; θ Pav 5.71; θ Pav 3.61; λ Pav 4.22; μ1 Pav 5.75; μ2 Pav 5.32; ν Pav 4.63; ・ Pav 4.35; ο Pav 5.06; ρ Pav 4.86; σ Pav 5.41; τ Pav 6.25; υ Pav 5.14; ω Pav 5.14; ω Pav 5.14; ω

Notable Deep Sky Objects

• NGC 6752, spectacular globular cluster at 13 000 light years, the third largest globular cluster in apparent size.
• NGC 6744, similar to the Milky Way, is one of the largest spiral galaxies observed. It is located 3.o southeast of λ Pavonis.
• NGC 6782, coiled spiral galaxy.

History

Since it was created in the 17th century and was not visible to Mediterranean cultures, there is no mythology associated with this constellation.