l Carinae

From Infogalactic: the planetary knowledge core
(Redirected from HD 84810)
Jump to: navigation, search

<templatestyles src="Module:Hatnote/styles.css"></templatestyles>

ℓ Carinae
Diagram showing star positions and boundaries of the Carina constellation and its surroundings
Cercle rouge 100%.svg

Location of l Carinae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Carina
Right ascension 09h 45m 14.81122s[1]
Declination –62° 30′ 28.4519″[1]
Apparent magnitude (V) 3.39[2] (3.35 - 4.06[3])
Characteristics
Spectral type F6Ib-K0Ib[3]
U−B color index +0.76[2]
B−V color index +1.03[2]
Variable type Classical Cepheid[3]
Astrometry
Radial velocity (Rv) +3.3[4] km/s
Proper motion (μ) RA: –12.88[1] mas/yr
Dec.: +8.19[1] mas/yr
Parallax (π) 2.09 ± 0.29[1] mas
Distance 525[5] pc
Absolute magnitude (MV) –5.22[6]
Details
Mass 8.4[7] to 13[8] M
Radius 169±8[5] R
Surface gravity (log g) 1.5[9] cgs
Temperature 5,091[9] K
Metallicity [Fe/H] 0.30[9] dex
Age 17-19[8] Myr
Other designations
l Carinae, 2MASS J09451481-6230284, CD–61 2349, FK5 1254, HD 84810, HIP 47854, HR 3884, IRAS 09438-6216, SAO 250683.
Database references
SIMBAD data
File:ESO - Model Image of Cepheid L Carinae (by).jpg
ESO - Model Image of Cepheid l Carinae

HD 84810, also known as l Carinae (l Car), is a star in the southern constellation of Carina. It has a mean apparent magnitude of +3.4,[2] making it readily visible to the naked eye and one of the brighter members of Carina. Based upon parallax measurements, it is approximately 1,600 light-years (490 parsecs) from Earth.[1]

From the characteristics of its spectrum, l Carinae has a stellar classification of G5 Iab/Ib.[7] This indicates the star has reached a stage in its evolution where it has expanded to become a supergiant with 169 times the radius of the Sun.[5] As this is a massive star with 8[7]–13[8] times the mass of the Sun, it rapidly burns through its supply of nuclear fuel and has become a supergiant in roughly 17-19 million years, after spending 15–17 million years as a main sequence star.[8]

l Carinae is classified as a Cepheid variable star and its brightness varies over an amplitude range of 0.725 in magnitude with a long period of 35.560 days. The radial velocity of the star likewise varies by 39 km/s during each pulsation cycle.[10] It has a compact circumstellar envelope that can be discerned using interferometry. The envelope has been resolved at an infrared wavelength of 10μm, showing a radius of 10–100 AU at a mean temperature of 100 K. The material for this envelope was supplied by mass ejected from the central star.[8]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found.
  2. 2.0 2.1 2.2 2.3 Lua error in package.lua at line 80: module 'strict' not found.
  3. 3.0 3.1 3.2 Lua error in package.lua at line 80: module 'strict' not found.
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. 5.0 5.1 5.2 Lua error in package.lua at line 80: module 'strict' not found.
  6. Lua error in package.lua at line 80: module 'strict' not found.
  7. 7.0 7.1 7.2 Lua error in package.lua at line 80: module 'strict' not found.
  8. 8.0 8.1 8.2 8.3 8.4 Lua error in package.lua at line 80: module 'strict' not found.
  9. 9.0 9.1 9.2 Lua error in package.lua at line 80: module 'strict' not found.
  10. Lua error in package.lua at line 80: module 'strict' not found.