page_title: Vela (constellation)
section_title: Stars
hierarchical_section_title: Vela (constellation) / Features / Stars
caption_attribution_description: English: The Very Large Telescope Interferometer at ESO’s Paranal Observatory in Chile has obtained the sharpest view ever of the dusty disc around the close pair of aging stars IRAS 08544-4431. For the first time such discs can be compared to the discs around young stars — and they look surprisingly similar. It is even possible that a disc appearing at the end of a star’s life might also create a second generation of planets. The inset shows the VLTI reconstructed image, with the brighter central star removed. The background view shows the surroundings of this star in the constellation of Vela (The Sails).
context_page_description: Vela is a constellation in the southern sky. Its name is Latin for the sails of a ship, and it was originally part of a larger constellation, the ship Argo Navis, which was later divided into three parts, the others being Carina and Puppis. With an apparent magnitude of 1.8, its brightest star is the hot blue multiple star Gamma Velorum, one component of which is the brightest Wolf-Rayet star in the sky. Delta and Kappa Velorum, together with Epsilon and Iota Carinae, form the asterism known as the False Cross. 1.95-magnitude Delta is actually a triple or quintuple star system.
context_section_description: 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. 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 our 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 brightest example in the sky. It has a surface temperature of 57,000 and is around 170,000 times as luminous as our sun, though it radiates most of its energy in the ultraviolet spectrum.  Gamma¹ is a blue-white star of spectral type B2III and apparent magnitude 4.3.  The two pairs are separated by 41 arcseconds, easily separable in binoculars.  Parallax measurements give a distance of 1,116 light-years, 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 Delta Velorum or Alsephina, also a multiple star system and one of the brightest eclipsing binaries in the sky. Together with Kappa Velorum or Markeb, Iota Carinae or Aspidiske and Epsilon Carinae or Avior, it forms the diamond-shaped asterism known as the False Cross—so called because it is sometimes mistaken for the Southern Cross, causing errors in astronavigation. Appearing as a white star of magnitude 1.95, Delta is actually a triple or possibly quintuple star system located around 80 light-years from the Solar System. Delta A has a magnitude of 1.99 and is an eclipsing binary composed of two A-type white stars (Delta Aa and Ab) which orbit each other every  45.2 days and lie 0.5 AU from each other, with a resulting drop in magnitude of 0.4 when the dimmer one passes.in front of the brighter. Delta B is a 5.1 magnitude yellow G-class star of similar dimensions to our sun which ranges between 26 and 72 AU away from the brighter pair, taking 142 years to complete a revolution. Further out still, at a distance of 1700 AU, are two red dwarfs of magnitudes 11 and 13. If they are part of the multiple system, they take 28000 years to complete an orbit. Also called Markeb, Kappa appears as a blue-white star of spectral type B2IV-V and magnitude 2.47 but is in fact a spectroscopic binary. The two orbit around each other with a period of 116.65 days, but the size, mass and nature of the companion are as yet unclear.
  The orange-hued Lambda Velorum, or Suhail, is the third-brightest star in the constellation. A supergiant of spectral type K4Ib-II, it varies between magnitudes 2.14 and 2.3, and lies 545 light-years distant. It has around 11,000 times the luminosity, 9 to 12 times the mass and 207 times the diameter or our sun.
  AH Velorum is a Cepheid variable located less than a degree to the northeast of Gamma. A yellow-white supergiant of spectral type F7Ib-II, it pulsates between magnitudes 5.5 and 5.89 over 4.2 days. Also lying close to Gamma, V Velorum is a Cepheid of spectral type F6-F9II ranging from magnitude 7.2 to 7.9 over 4.4 days. AI Velorum is located 2.8 degrees north-northeast of Gamma, a Delta Scuti variable of spectral type A2p-F2pIV/V that ranges between magnitudes 6.15 and 6.76 in around 2.7 hours.
  V390 Velorum is an aged star that has been found to be surrounded by a dusty disk. An RV Tauri variable, it has a spectral type of F3e and ranges between magnitudes 9.01 and 9.27 over nearly 95 days.
  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. It is the brightest star in, and gives its name to, the Omicron Velorum Cluster, also known as IC 2391, an open cluste
caption: Dusty ring around double star IRAS 08544-4431.[8]
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