FU Orionis

Source: Wikipedia, the free encyclopedia.
This article is about the particular star. For the type of variable stars named after this star, see
FU Orionis stars
.
FU Orionis

The blue band light curve for FU Orionis, adapted from Clarke et al. (2005).[1] The inset plot, adapted from Siwak, et al. (2013),[2] illustrates the short timescale variability.
Observation data
ICRS
)
Constellation Orion
Right ascension 05h 45m 22.362s[3]
Declination +09° 04′ 12.31″[3]
Apparent magnitude (V) 8.94[3]
Characteristics
Spectral type uncertain + K5+2
−1[4]
B−V color index 1.41[3]
Variable type FU Ori[5]
Distance
1,360 ± 30 ly
(416 ± 9 pc)
Details
FU Orionis north
Myr
Other designations
FU Ori, BD+09 5427.[3]
Database references
SIMBADdata

FU Orionis is a

variable star designation in the Argelander system, which are assigned sequentially as new variables are discovered.[10] FU Orionis is about 1,360 light years distant and is associated with the molecular cloud Barnard 35.[6][11]

For a long time this variable was considered unique, but in 1970 a similar star,

pre–main sequence stars
which display an extreme change in magnitude and spectral type.

Stellar system

FU Orionis consists of two components, both surrounded by a

circumstellar disk. Both disks were resolved with ALMA. The primary is surrounded by a dust disk with a radius of 11 astronomical units and the secondary disk has a similar inclination and size. The disks are separated by about 250 au. The 12CO emission show a complex kinematic environment and signatures of disk rotation, which are asymmetric. The asymmetry of the disk rotation is explained with interactions of the disks during a stellar flyby.[7]

The primary, called FU Orionis north has a mass of 0.6 M☉ and accretes M☉ per year.

near-infrared.[12] The secondary, called FU Orionis south could be the more massive component in the system with 1.2 M☉ and a spectral type of about K5.[4]

Nebula

FU Orionis is associated with the molecular cloud Barnard 35 (part of the Lambda Orionis Ring) and close to the star an arc-shaped nebula is visible. Other FU Orionis stars are associated with an arc-shaped reflection nebula that becomes visible as the star brightens.[13][11]

References

  1. doi:10.1111/j.1365-2966.2005.09231.x
    .
  2. doi:10.1093/mnras/stt441
    .
  3. ^ a b c d e f "V* FU Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved December 8, 2008.
  4. ^
    ISSN 0004-6256
    .
  5. ^ FU Ori, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars Archived 2017-06-20 at the Wayback Machine, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line December 8, 2008.
  6. ^
    S2CID 49211658
    .
  7. ^
    S2CID 208291454
    .
  8. S2CID 17793369
    .
  9. ^ AAVSO: FU Orionis
  10. doi:10.1086/122431
    .
  11. ^
    ISSN 0004-637X
    .
  12. ISSN 0004-6361
    .
  13. ^ "FU Orionis | aavso.org". www.aavso.org. Retrieved 2020-02-08.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=FU_Orionis&oldid=1188015012"