Puppis constellation is located in the southern hemisphere. It represents the stern of a ship. Puppis is the 20th constellation in size, occupying an area of 673 square degrees. It lies in the second quadrant of the southern hemisphere (SQ2) and can be seen at latitudes between +40° and -90°. The neighboring constellations are Carina, Canis Major, Columba, Hydra, Monoceros, Pictor, Pyxis and Vela. Puppis belongs to the Heavenly Waters family of constellations, along with Carina, Columba, Delphinus, Equuleus, Eridanus, Piscis Austrinus, Pyxis, and Vela.
[http://www.constellation-guide.com/constellation-list/puppis-constellation/]
An excerpt from Johan van Keulen’s Boeck zee-kaardt, 1709. Puppis represents the Stern of the Ship. In the water below it play two fishes, Dorado and Volans, and Columba the Dove flies back to the ship behind it.
[http://www.stargazers.iinet.net.au/puppis.htm]
Puppis, the Poop Deck, was originally part of an over-large constellation, the ship of ‘Jason and the Argonauts,’ Argo Navis, which centuries after its initial description, was divided in 1752 by the French astronomer Nicolas Louis de Lacaille into three parts, the other two being Carina (the keel and hull), and Vela (the sails of the ship).
[http://astropixels.com/constellations/charts/Pup.html]
[http://www.dibonsmith.com/pup_con.htm]
Stars in Puppis include:
Artistic depiction of Zeta Puppis (Naos)
Zeta Puppis is the brightest star in the constellation of Puppis. It is also known by the traditional names Naos (from the Greek ναύς ‘ship’) and Suhail Hadar (possibly ‘roaring bright one’ in Arabic). The spectral class of O4 means this is one of the hottest, and most luminous, stars visible to the naked eye. It is one of the sky’s few naked-eye class O-type stars as well as one of the closest to Earth. It is a blue supergiant, one of the most luminous stars in the Milky Way. Visually it is over 10,000 times brighter than the Sun, but its high temperature means that most of its radiation is in the ultraviolet and its bolometric luminosity is over 500,000 times that of the Sun. It is also the 62nd brightest star in terms of apparent magnitude from Earth.
[https://en.wikipedia.org/wiki/Zeta_Puppis]
Collinder 135, known sometimes as the Pi Puppis Cluster
[https://en.wikipedia.org/wiki/Collinder_135]
The spectrum of Pi Puppis matches a stellar classification of K3 Ib. The Ib luminosity class indicates this a lower luminosity supergiant star that has consumed the hydrogen fuel at its core, evolved away from the main sequence, and expanded to about 290 times the Sun's radius. The effective temperature of the star’s outer envelope is about 4,000 K, which gives it the orange hue of a K-type star. It is a semiregular variable star that varies in apparent magnitude from a high of 2.70 down to 2.85. Pi Puppis is the brightest star in the open cluster Collinder 135.
[https://en.wikipedia.org/wiki/Pi_Puppis]
SPHERE and VLT NACO image of the nebulosity forming around L2 Puppis
L2 Puppis (also known as HD 56096) is a giant star in the constellation of Puppis and is located between the bright stars Canopus and Sirius. It is a semi-regular pulsating star that varies in apparent magnitude from 2.60 down to 6.00 with a period of 140.83 days. The variation in light may be caused by a combination of radial pulsations in the star’s atmosphere and by dimming from circumstellar dust. This is most likely an asymptotic giant branch star that has passed through the main sequence and is evolving to become a white dwarf. It is shedding mass at the rate of about 2.2×10^9 solar masses per year. Recently the star has had an apparent magnitude range of about 6.9 to 8. L2 Puppis has a visual 10th magnitude companion about a minute of arc away.
[https://en.wikipedia.org/wiki/L2_Puppis]
[http://www.solstation.com/stars2/hd69830.htm]
HD 69830 (285 G. Puppis) is a yellow dwarf star approximately 41 light-years away in the constellation of Puppis. In 2005, the Spitzer Space Telescope discovered a debris disk orbiting the star. The disk contains substantially more dust than the Solar System’s asteroid belt. As of 2006, it has been confirmed that three extrasolar planets with minimum masses comparable to Neptune orbit the star, located interior to the debris disk.
[https://en.wikipedia.org/wiki/HD_69830]
Artist impression of possible moons around the planet HD 70642b
[https://jumk.de/astronomie/exoplanets/hd-70642.shtml]
HD 70642 is a yellow dwarf star in the constellation of Puppis located 92 light years away. This star has about the same mass and radius as the Sun, is slightly cooler and less luminous, and is richer in abundance of iron relative to hydrogen. A long period planet companion to HD 70642 was announced in 2003. This planet orbits in a circular orbit (e=0.034) at 3.232 AU. The star is so like to Sol that its habitable zone is in the same place (~1 AU). The jovian planet ensures the stability of an Earth-mass planet at 1 AU. This system is one of the most similar in conditions to the Solar System than any other currently known planetary systems.
[https://en.wikipedia.org/wiki/HD_70642]
RS Puppis as imaged by Hubble
RS Puppis (or RS Pup) is a Cepheid variable star in the constellation of Puppis. It is one of the brightest known Cepheids in the Milky Way galaxy and has one of the longest periods of 41.4 days. Because it is located in a large nebula, astronomers using the ESO’s New Technology Telescope at La Silla Observatory, Chile have been able to measure its distance in 2013 by strictly geometric analysis of light echoes from particles in the nebula, determining it to be 6500 ± 90 light years from Earth, the most accurate measurement achieved for any Cepheid as of early 2008. The accuracy of the new measurement is important because Cepheids serve as a marker for distances within our galaxy and for nearby galaxies.
[https://en.wikipedia.org/wiki/RS_Puppis]
V445 Puppis is a recurrent nova in the constellation Puppis. It was discovered by Kazuyoshi Kanatsu who recorded a peak magnitude of 8.6 on November 28, 2000. The location of this nova coincided with a magnitude 13.1 star that had been photographed in 1967.
Examination of the optical spectrum of this nova showed the initial spectrum was deficient in hydrogen and did not match those typical of other nova types. The infrared spectrum measured on January 31 showed a featureless continuum that decreased with increasing wavelength. This is consistent with emission from heated dust and suggests that the star is a nova that has generated dust during prior outbursts. By 2004, the object had faded and the dust emission had disappeared.
The deficient level of hydrogen in this outburst, along with an enrichment of helium and carbon, and a higher level of ionization, suggested that it was the first observed instance of a helium nova. This is theorized to occur when a white dwarf star predominantly accretes helium (rather than hydrogen) from an orbiting companion. When sufficient helium has accumulated along a shell on the surface of the white dwarf, a run-away thermonuclear explosion results in a nova outburst. Hence, V445 Puppis may belong to a binary star system and be surrounded by an accretion disk of matter drawn from the companion star.
The white dwarf in the V445 Puppis system has an estimated mass of more than 1.3 times the mass of the Sun, and this mass is increasing because of recurring helium shell flashes from accreted material. As the mass of the white dwarf approaches the Chandrasekhar limit of about 1.38 solar masses, it will likely explode as a Type Ia supernova.
At present, the system is being obscured by an optically thick cloud of dust. A bi-polar outflow of material has been observed moving away from the system at a velocity of 6,720 ± 650 km s−1. Based upon the expansion parallax for this outflow, the system lies at a distance of 8.2 ± 0.5 kpc.
[https://en.wikipedia.org/wiki/V445_Puppis]
As the Milky Way runs through Puppis, there are a large number of open clusters in the constellation. M46 and M47 are two open clusters in the same binocular field. Superimposed onto M46 is the planetary nebula NGC 2438:
M46 & M47: Star clusters young and old
Many stars form in clusters. Galactic or open star clusters are relatively young swarms of bright stars born together near the plane of our Milky Way Galaxy. Separated by about a degree on the sky, two nice examples are M46 (upper left) 5,400 light-years in the distance and M47 (lower right) only 1,600 light-years away toward the nautical constellation Puppis. Around 300 million years young M46 contains a few hundred stars in a region about 30 light-years across. Aged 80 million years, M47 is a smaller but looser cluster of about 50 stars spanning 10 light-years. But this portrait of stellar youth also contains an ancient interloper. The small, colorful patch of glowing gas in M46 is actually the planetary nebula NGC 2438 - the final phase in the life of a sun-like star billions of years old. NGC 2438 is estimated to be only 3,000 light-years distant and likely represents a foreground object, only by chance appearing along our line of sight to youthful M46.
[https://apod.nasa.gov/apod/ap120403.html]
Planetary nebula NGC 2438
NGC 2438 is a planetary nebula, the gaseous shroud cast off by a dying sunlike star billions of years old whose central reservoir of hydrogen fuel has been exhausted. About 3,000 light-years distant it lies within the boundaries of the nautical constellation Puppis. Remarkably, NGC 2438 also seems to lie on the outskirts of bright, relatively young open star cluster M46. But this planetary nebula’s central star is not only much older than the stars of M46, it moves through space at a different speed than the cluster stars. Distance estimates also place NGC 2438 closer than M46 and so the nebula appears in the foreground, only by chance along the line-of-sight to the young star cluster. This deep image of NGC 2438 highlights a halo of glowing atomic gas over 4.5 light-years across, extending beyond the nebula’s brighter inner ring. Similar haloes have been found in deep images of other planetary nebulae, produced during the earlier active phases of their aging central stars.
[http://apod.nasa.gov/apod/ap110407.html]
NGC 2440 is another planetary nebula in Puppis. It has an apparent magnitude of 9.4 and is approximately 4,000 light years distant from Earth. The central star in the nebula, HD 62166, is possibly the hottest white dwarf known. It has a surface temperature of 200,000 kelvins and is 1,100 times more luminous than the Sun. It has 0.6 times the mass of the Sun and only 0.028 times the solar radius. The star has an apparent magnitude of 17.5. The nebula was discovered by William Herschel on March 4, 1790:
[http://www.constellation-guide.com/constellation-list/puppis-constellation/]
Planetary nebula NGC 2440
Planetary nebula NGC 2440 has an intriguing bow-tie shape in this stunning view from space. The nebula is composed of material cast off by a dying sun-like star as it enters its white dwarf phase of evolution. Details of remarkably complex structures are revealed within NGC 2440, including dense ridges of material swept back from the nebula’s central star. Near the center of the view, the star itself is one of the hottest known, with a surface temperature of about 200,000 kelvins. About 4,000 light-years from planet Earth toward the nautical constellation Puppis, the nebula spans over a light-year and is energized by ultraviolet light from the central star. The false-color image was recorded earlier this month using the Hubble's Wide-Field Planetary Camera 2(WFPC2), demonstrating still impressive imaging capabilities following the failure of the Advanced Camera for Surveys.
[https://apod.nasa.gov/apod/ap070215.html]
NGC 2467 is a star-forming region in Puppis, popularly known as the ‘Skull and Crossbones nebula,’ whose appearance has occasionally also been likened to that of a colorful mandrill. It includes areas where large clouds of hydrogen gas incubate new stars:
[https://en.wikipedia.org/wiki/NGC_2467]
NGC 2467: From gas to stars
One might guess that the group of stars on the left is responsible for shaping the gas cloud on the right- but it probably is not. Observations of many of the stars in the NGC 2467 show them to be more a superposition of loose groups of stars at different distances than a coherent open cluster of stars energizing the nebula. Still, the above image captures various stages of star formation. The stars at the far left have already formed and their birth nebulae have already dispersed. At the lower left lies a very young star that is breaking free of its surrounding birth cocoon of gas. On the right of the above image, a bright wall of bright gas glows as it evaporates from the energy of many newly formed bright stars. Toward the center, deep dark lanes of dust hide parts of the nebula that surely are forming new stars. The 8-meter Gemini South Telescope, perched on a mountaintop in Cerro Pachon, Chile, took the above image. NGC 2467 lies toward the southern constellation of Puppis, with many of the stars being about 17,000 light years distant.
[http://apod.nasa.gov/apod/ap050131.html]
CG 4, commonly referred to as God’s Hand, is another star-forming region located in the Puppis constellation, about 1,300 light-years (400 pc) from Earth. Its head is about 1.5 ly (0.46 pc) in diameter and its tail is about 8 ly (2.5 pc) long. It is a cometary globule, one side of which has been blown outwards into a long tail, resembling a comet and hence named so:
[https://en.wikipedia.org/wiki/CG_4]
Cometary globule CG4
The faint and somehow menacing cometary globule CG4 reaches through the center of this deep southern skyscape. About 1,300 light-years from Earth toward the constellation Puppis, its head is about 1.5 light-years in diameter and its tail about 8 light-years long. That's far larger than the Solar System's comets that it seems to resemble. In fact, the dusty cloud contains enough material to form several Sun-like stars and likely has ongoing star formation within. How its distinctive form came about is still debated, but its long tail trails away from the Vela Supernova remnant near the center of the Gum Nebula, while its head could represent the rupture of an originally more spherical cloud. Still, the edge-on spiral galaxy also near picture center is not actually being threatened by CG4. The galaxy lies in the distant background more than 100 million light-years away.
[https://apod.nasa.gov/apod/ap150306.html]
Puppis A (Pup A) is a supernova remnant (SNR) about 100 lightyears in diameter and roughly 6500- 7000 lightyears distant. Its apparent angular diameter is about 1 degree. The light of the supernova explosion reached Earth approximately 3700 years ago. Although it overlaps the Vela Supernova Remnant, it is four times more distant. A hypervelocity neutron star known as the Cosmic Cannonball has been found in this SNR:
Puppis A: Chandra reveals cloud disrupted by supernova shock
The Chandra three-color image (inset) of a region of the supernova remnant Puppis A (wide-angle view from ROSAT in blue) reveals a cloud being torn apart by a shock wave produced in a supernova explosion. This is the first X-ray identification of such a process in an advanced phase. In the inset, the blue vertical bar and the blue fuzzy ball or cap to the right show how the cloud has been spread out into an oval-shaped structure that is almost empty in the center. The Chandra data also provides information on the temperature in and around the cloud, with blue representing higher temperature gas.
The oval structure strongly resembles those seen on much smaller size scales in experimental simulations of the interaction of supernova shock waves with dense interstellar clouds (see sequence of laboratory images). In these experiments, a strong shock wave sweeps over a vaporized copper ball that has a diameter roughly equal to a human hair. The cloud is compressed, and then expands in about 40 nanoseconds to form an oval bar and cap structure much like that seen in Puppis A.
On a cosmic scale, the disruption of l0-light-year-diameter cloud in Puppis A took a few thousand years. Despite the vast difference in scale, the experimental structures and those observed by Chandra are remarkably similar. The similarity gives astrophysicists insight into the interaction of supernova shock waves with interstellar clouds.
Understanding this process is important for answering key questions such as the role supernovas play in heating interstellar gas and triggering the collapse of large interstellar clouds to form new generations of stars.
[http://chandra.harvard.edu/photo/2006/puppisa/]
[https://en.wikipedia.org/wiki/Puppis]
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