Vela (constellation)
Constellation | |
32nd) | |
Main stars | 5 |
---|---|
Bayer/Flamsteed stars | 50 |
Stars with planets | 7 |
Stars brighter than 3.00m | 5 |
Stars within 10.00 pc (32.62 ly) | 3 |
Brightest star | γ Vel (1.75m) |
Messier objects | 0 |
Meteor showers | Delta Velids Gamma Velids Puppid-velids |
Bordering constellations | Antlia Pyxis Puppis Carina Centaurus |
Visible at latitudes between +30° and −90°. Best visible at 21:00 (9 p.m.) during the month of March. |
Vela is a
History
Argo Navis was one of the 48 classical constellations listed by the 2nd-century astronomer Ptolemy, and represented the ship Argo, used by Jason and the Argonauts on their quest for the Golden Fleece in Greek mythology. German cartographer Johann Bayer depicted the constellation on his Uranometria of 1603, and gave the stars Bayer designations from Alpha to Omega. However, his chart was inaccurate as the constellation was not fully visible from the Northern Hemisphere.[1]
Argo was more accurately charted and subdivided in 1752 by the French astronomer
Characteristics
Vela is bordered by
The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 14 segments. In the equatorial coordinate system, the right ascension coordinates of these borders lie between 08h 13.3m and 11h 05.5m , while the declination coordinates are between −37.16° and −57.17°.[3]
Features
Stars
The brightest star in the constellation, Gamma Velorum, is a complex multiple star system. The brighter component, known as Gamma2 Velorum, shines as a blue-white star of apparent magnitude 1.83.[4] It is a spectroscopic binary made up of two very hot blue stars orbiting each other every 78.5 days and separated by somewhere between 0.8 and 1.6 Astronomical Units (AU). The brighter component is a hot blue main-sequence star of spectral type O7.5 and is around 280,000 times as luminous, is around 30 times as massive and is 17 times the diameter of the Sun with a surface temperature of 35,000 K. The second component is an extremely rare example of hot star known as a Wolf–Rayet star, and is the closest and brightest example in the sky. It has a surface temperature of 57,000 and is around 170,000 times as luminous as the Sun, though it radiates most of its energy in the ultraviolet spectrum.[5] Gamma1 is a blue-white star of spectral type B2III and apparent magnitude 4.3.[6] The two pairs are separated by 41 arcseconds, easily separable in binoculars.[6] Parallax measurements give a distance of 1,116 light-years,[7] meaning that they are at least 12,000 AU apart. Further afield are 7.3-magnitude Gamma Velorum C and 9.4-magnitude Gamma Velorum D, lying 62 and 93 arcseconds south-southeast from Gamma2.
The next brightest star is
The orange-hued Lambda Velorum, or Suhail,[9] is the third-brightest star in the constellation. A supergiant of spectral type K4Ib-II, it varies between magnitudes 2.14 and 2.3,[16] and lies 545 light-years distant.[17] It has around 11,000 times the luminosity, 9 to 12 times the mass and 207 times the diameter of the Sun.[18]
Omicron Velorum is a blue-white subgiant of spectral type B3III-IV located around 495 light-years from the Solar System. A slowly pulsating B star, it ranges between magnitudes 3.57 and 3.63 over 2.8 days.[25] It is the brightest star in, and gives its name to, the Omicron Velorum Cluster, also known as IC 2391, an open cluster located around 500 light-years away.
Seven star systems have been found to have
HD 85390 is an orange dwarf of spectral type K1.5V lying around 111 light-years distant with a planet 42 times as massive as Earth orbiting every 788 days.
HD 93385 is a Sun-like star of spectral type G2/G3V located around 138 light-years away that is orbited by two super-Earths with periods of 13 and 46 days and masses 8.3 and 10.1 times that of Earth, respectively.
Brown dwarfs
The discovery of a binary brown dwarf system named Luhman 16 only 6.6 light-years away, the third-closest system to the Solar System, was announced on 11 March 2013.
Deep-sky objects
Of the deep-sky objects of interest in Vela is a planetary nebula known as NGC 3132, nicknamed the 'Eight-Burst Nebula' or 'Southern Ring Nebula' (see accompanying photo). It lies on the border of the constellation with Antlia.[19] NGC 2899 is an unusual red-hued example. This constellation has 32 more planetary nebulae.
The Gum Nebula is a faint emission nebula, believed to be the remains of a million-year-old supernova. Within it lies the smaller and younger Vela Supernova Remnant. This is the nebula of a supernova explosion that is believed to have been visible from Earth around 10,000 years ago. The remnant contains the Vela Pulsar, the first pulsar to be identified optically. Nearby is NGC 2736, also known as the Pencil Nebula.
NGC 2670 is an open cluster located in Vela. It has an overall magnitude of 7.8 and is 3,200 light-years from Earth. The stars of NGC 2670, a Trumpler class II 2 p and Shapley class-d cluster, are in a conformation suggesting a bow and arrow. Its class indicates that it is a poor, loose cluster, though detached from the star field. It is somewhat concentrated at its center, and its less than 50 stars range moderately in brightness.[27]
Located 2 degrees south of Gamma Velorum, NGC 2547 is an open cluster containing around 50 stars of magnitudes 7 to 15.[19]
NGC 3201 is a globular cluster discovered by James Dunlop on May 28, 1826. Its stellar population is inhomogeneous, varying with distance from the core. The effective temperature of the stars shows an increase with greater distance, with the redder and cooler stars tending to be located closer to the core. As of 2010, is one of only two clusters (including Messier 4) that shows a definite inhomogeneous population.[28]
RCW 36 is a star-forming region in Vela, and one of the nearest sites of massive star formation. This star-forming region has given rise to a cluster of several hundred young stars that power an HII region.[29] The star-forming region lies in Clump 6 in the Vela Molecular Ridge Cloud C.[30]
References
- ^ ISBN 978-0-939923-78-6.
- Bibcode:1922PA.....30..469R.
- ^ "Vela, constellation boundary". The Constellations. International Astronomical Union. Retrieved 6 October 2013.
- Bibcode:2002yCat.2237....0D.
- S2CID 16425744.
- ^ S2CID 17560818.
- S2CID 18759600
- ^ "Sharpest View Ever of Dusty Disc Around Aging Star". Retrieved 23 March 2016.
- ^ a b c d e "Naming Stars". IAU.org. Retrieved 8 August 2018.
- ISBN 978-1-4441-2977-9.
- ^ "V* Delta Velorum -- Eclipsing binary of Algol type (detached)". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 11 October 2013.
- ^ Kaler, Jim. "Delta Velorum". Stars. University of Illinois. Retrieved 11 October 2013.
- ^ "Kappa Velorum - Spectroscopic binary". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 10 October 2013.
- S2CID 119387088
- ^ Kaler, Jim. "Markeb". Stars. University of Illinois. Retrieved 11 October 2013.
- ^ "Lambda Velorum". International Variable Star Index. American Association of Variable Star Observers. 25 September 2009. Retrieved 11 October 2013.
- ^ "V* Lambda Velorum -- Pulsating Variable Star". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 10 October 2013.
- ^ Kaler, Jim. "Suhail". Stars. University of Illinois. Retrieved 10 October 2013.
- ^ ISBN 978-1-85410-088-7.
- ^ "AH Velorum". International Variable Star Index. American Association of Variable Star Observers. 4 January 2010. Retrieved 11 October 2013.
- ISBN 978-0-521-79390-2.
- ^ "V Velorum". International Variable Star Index. American Association of Variable Star Observers. 4 January 2010. Retrieved 11 October 2013.
- ^ "AI Velorum". International Variable Star Index. American Association of Variable Star Observers. 11 September 2011. Retrieved 10 August 2022.
- ^ "V0390 Velorum". International Variable Star Index. American Association of Variable Star Observers. 25 May 2011. Retrieved 11 October 2013.
- ^ "Omicron Velorum". International Variable Star Index. American Association of Variable Star Observers. 10 February 2012. Retrieved 11 October 2013.
- ^ Foncea, Valeria; Arce; Héctor (20 August 2013). "ALMA Takes Close Look at Drama of Starbirth". Atacama Large Millimeter/Submillimeter Array. Archived from the original on 27 September 2013. Retrieved 11 October 2013.
- ^ Levy 2005, p. 87.
- S2CID 118407774.
- S2CID 56189137.
- .
- Levy, David H. (2005), Deep Sky Objects, Prometheus Books, ISBN 1-59102-361-0
- Ian Ridpath and Wil Tirion (2017). Stars and Planets Guide, Collins, ISBN 978-0691177885.
- Richard Hinckley Allen, Star Names, Their Lore and Legend, New York, Dover, various dates.