HD 93129 surrounded by the lesser stars of Trumpler 14 Credit: NASA & ESA, Jesús Maíz Apellániz (Instituto de Astrofisica de Andalucia) | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Carina |
Right ascension | 10h 43m 57.5s [1] |
Declination | −59° 32′ 51.3″ [1] |
Apparent magnitude (V) | 6.90 [2] (7.310 [1] + 8.84 [3] ) |
Characteristics | |
A | |
Spectral type | O2If* [4] (O2If+O3.5V [5] ) |
U−B color index | −0.81 [3] |
B−V color index | +0.25 [3] |
B | |
Evolutionary stage | main sequence |
Spectral type | O3.5 V((f))z [6] |
U−B color index | −0.79 [3] |
B−V color index | +0.23 [3] |
Astrometry | |
Radial velocity (Rv) | −0.4 ± 7.4 [7] km/s |
Proper motion (μ) | RA: -5.0 [1] mas/yr Dec.: 17.0 [1] mas/yr |
Distance | 2,300 [5] pc |
Absolute magnitude (MV) | (A): −6.5 (−6.1 + −5.2) (B): −4.9 [8] |
Details | |
Aa | |
Mass | 110 [8] M☉ |
Radius | 22.5 [9] R☉ |
Luminosity | 1,480,000 [10] L☉ |
Surface gravity (log g) | 3.71 [9] cgs |
Temperature | 42,500 [9] K |
Rotational velocity (v sin i) | 130 [9] km/s |
Age | 0.9+0.2 −0.4 [7] Myr |
Ab | |
Mass | 70 [8] M☉ |
Radius | 13.1 [11] R☉ |
Luminosity | 575,000 [10] L☉ |
Temperature | 44,000 [11] K |
B | |
Mass | 52 [12] M☉ |
Radius | 13 [12] R☉ |
Luminosity | 575,000 [10] L☉ |
Surface gravity (log g) | 3.92 [12] cgs |
Temperature | 44,000 [12] K |
Rotational velocity (v sin i) | 112 [7] km/s |
Other designations | |
A: TYC 8626-2805-1, ALS 15862, LS 1820 | |
B: ALS 19309 | |
Database references | |
SIMBAD | HD 93129 |
HD 93129 A | |
HD 93129 B |
HD 93129 is a triple star system in the Carina Nebula, with all three components being hot O class stars amongst the most luminous stars in the Milky Way. It is the dominant member of the Trumpler 14 star cluster, a young star cluster within the Carina OB1 stellar association that harbors other super-luminous stars, like Eta Carinae and WR 25.
HD 93129 is found at the centre of the massive Trumpler 14 open cluster in the Carina Nebula star forming region. It is too far away for its distance to have been accurately determined using the annual parallax method, but accurate distances for η Carinae and the Homunculus Nebula, modelling of clusters, and astrophysical data about other stars assumed to be within the same region, all lead to a distance around 2,300 parsecs. [5] HD 93129 Aa is the closest O2 supergiant to Earth. [13]
That volume of space is home to many other massive and luminous stars. HD 93128, yet another O3.5 main sequence star, is only 24' away within Trumpler 14, and HD 93250 and HD 93205 are two more O3.5 stars in the larger Trumpler 16 cluster around η Carinae. There are also three Wolf-Rayet stars, an O4 supergiant, many other class O stars, and the unique η Carinae itself. [10]
HD 93129 consists of two clearly resolved components, HD 93129 A and HD 93129 B, and HD 93129 A itself is made up of two much closer stars.
HD 93129 A has been resolved into two components. The spectrum is dominated by the brighter component, although the secondary is only 0.9 magnitudes fainter. HD 93129 Aa is an O2 supergiant and Ab is an O3.5 main sequence star. [14] Their separation has decreased from 55 mas in 2004 to only 27 mas in 2013, but an accurate orbit is not available. [13]
HD 93129 B is an O3.5 main-sequence star 3 arc-seconds away from the closer pair. It is about 1.5 magnitudes fainter than the combined HD 93129 A, and approximately the same brightness as HD 93129 Ab. [1] [3]
A further 5 fainter stars within 5 arc-seconds have been detected, between five and seven magnitudes fainter at infrared wavelengths. [13]
All three stars of HD 93129 are among the most luminous in the galaxy; [5] 1,480,000 L☉ for the supergiant primary and 575,000 L☉ for each of the other two stars. They are also among the hottest, with the supergiant at 42,500 K and the other two at 52,000 K. The stars have masses calculated to be between 70 M☉ and 110 M☉.
HD 93129Aa has left the main sequence and its age is estimated to be around 900,000 years. The existence of the zero-age main sequence stars within Trumpler 14 suggest its age may be less than 600,000 years. [7]
Eta Carinae, formerly known as Eta Argus, is a stellar system containing at least two stars with a combined luminosity greater than five million times that of the Sun, located around 7,500 light-years distant in the constellation Carina. Previously a 4th-magnitude star, it brightened in 1837 to become brighter than Rigel, marking the start of its so-called "Great Eruption". It became the second-brightest star in the sky between 11 and 14 March 1843 before fading well below naked-eye visibility after 1856. In a smaller eruption, it reached 6th magnitude in 1892 before fading again. It has brightened consistently since about 1940, becoming brighter than magnitude 4.5 by 2014.
The Carina Nebula or Eta Carinae Nebula is a large, complex area of bright and dark nebulosity in the constellation Carina, located in the Carina–Sagittarius Arm of the Milky Way galaxy. The nebula is approximately 8,500 light-years (2,600 pc) from Earth.
NGC 3603 is a nebula situated in the Carina–Sagittarius Arm of the Milky Way around 20,000 light-years away from the Solar System. It is a massive H II region containing a very compact open cluster HD 97950.
AG Carinae is a star in the constellation Carina. It is classified as a luminous blue variable (LBV) and is one of the most luminous stars in the Milky Way. The great distance and intervening dust mean that the star is not usually visible to the naked eye; its apparent brightness varies erratically between magnitude 5.7 and 9.0.
Pismis 24-1, also known as HD 319718, is the brightest star of the open cluster Pismis 24 within the nebula NGC 6357 about 6,500 light-years away. It was once thought to be the most massive star known, but is composed of at least three individual objects, each still among the most luminous and most massive stars known.
HD 93205, or V560 Carinae, is a binary stellar system, in the Carina Nebula in the constellation Carina. It consists of two massive O-stars that revolve around each other in 6 days.
HD 93250 is a highly luminous hot blue binary star in the Carina Nebula in the constellation Carina.
HR Carinae is a luminous blue variable star located in the constellation Carina. It is surrounded by a vast nebula of ejected nuclear-processed material because this star has a multiple shell expanding atmosphere. This star is among the most luminous stars in the Milky Way. It has very broad emission wings on the Balmer lines, reminiscent from the broad lines observed in the spectra of O and Wolf–Rayet stars. A distance of 5 kpc and a bolometric magnitude of -9.4 put HR Car among the most luminous stars of the galaxy.
Melnick 42 is a massive blue supergiant star in the Tarantula Nebula in the Large Magellanic Cloud located in the constellation Dorado. Although it is only 21 times the size of the sun, its high temperature of 47,300 K makes it one of the most luminous stars of the Tarantula Nebula at 3,600,000 L☉. It is less than two parsecs from the centre of the R136 cluster, although that is well outside the central core.
RT Carinae, also known as CD-58 3538, is a variable star in the Carina Nebula in the constellation Carina. It has a mean apparent magnitude of +8.55.
WR 25 is a binary star system in the turbulent star-forming region the Carina Nebula, about 6,800 light-years from Earth. It contains a Wolf-Rayet star and a hot luminous companion and is a member of the Trumpler 16 cluster. The name comes from the Catalogue of Galactic Wolf–Rayet Stars.
WR 24 is a Wolf-Rayet star in the constellation Carina. It is one of the most luminous stars known. At the edge of naked eye visibility it is also one of the brightest Wolf Rayet stars in the sky.
An O-type star is a hot, blue-white star of spectral type O in the Yerkes classification system employed by astronomers. They have temperatures in excess of 30,000 kelvin (K). Stars of this type have strong absorption lines of ionised helium, strong lines of other ionised elements, and hydrogen and neutral helium lines weaker than spectral type B.
Trumpler 16 is a massive open cluster that is home to some of the most luminous stars in the Milky Way galaxy. It is situated within the Carina Nebula complex in the Carina–Sagittarius Arm, located approximately 9,270 ly (2,842 pc) from Earth. The cluster has one star visible to the naked eye from the tropics southward, Eta Carinae.
Trumpler 14 is an open cluster with a diameter of six light-years (1.8 pc), located within the inner regions of the Carina Nebula, approximately 8,980 light-years (2,753 pc) from Earth. Together with the nearby Trumpler 16, they are the main clusters of the Carina OB1 stellar association, which is the largest association in the Carina Nebula, although Trumpler 14 is not as massive or as large as Trumpler 16.
HD 93403 is a spectroscopic binary containing two highly luminous hot blue stars. It is 10,000 light years away in the Carina Nebula in the constellation Carina. It appears to have spectral type O5.5III, but this is composed of two spectra from a blue supergiant and blue main sequence star of spectral type O5.5I and O7V respectively. The two stars orbit every 15 days with a separation that varies from 93 R☉ to 149 R☉. The binary is shedding mass at the high rate of 0.0005 M☉ per year.
HD 15558 is a massive O-type multiple star system in Cassiopeia and is specifically in our galaxy's Heart Nebula in open cluster IC 1805. The primary is a very massive star with 152 M☉ and 660,000 L☉.
BO Carinae, also known as HD 93420, is an irregular variable star in the constellation Carina.
Collinder 228 is an open cluster within the southern part of the Carina Nebula NGC 3372, about 25' south of η Carinae. It is probably composed of stars which recently formed from the material in the nebula. QZ Carinae is the brightest member of Collinder 228 with an apparent magnitude between 6.16 and 6.49.