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Variable star in the constellation Hydra
W Hydrae
Observation data
Epoch
J2000.0
Equinox
J2000.0
Constellation
Hydra
Right ascension
13h 49m 01.998s
Declination
−28° 22′ 03.49″
Apparent magnitude (V)
7.7 - 11.6
[2]
Characteristics
Spectral type
M7.5e-M9ep
[3]
Apparent magnitude (
J )
-1.7
[4]
Variable type
Mira
Astrometry
Parallax (π) 10.18 ± 2.36
mas
[5]
Distance 98
[6]
pc
Details
Radius 229
[7] –560
[8]
R ☉
Luminosity 7,330
[6]
L ☉
Temperature 2,500
[9] - 3,129
[7]
K
Other designations
W Hya, CCDM J13491-2822A,
HD 120285,
RAFGL 1650,
CPD -27° 4792,
HIP 67419,
SAO 181981,
AAVSO 1343-27,
IRAS 13462-2807,
GC 18659,
TYC 6728-19-1.
Database references
SIMBAD
data
W Hydrae is a
Mira-type variable star in the
constellation
Hydra .
The star is nearly located within the Solar neighborhood, between 75 and 120
parsecs , likely at 320
light years from the
Sun . It has a
visual
apparent magnitude range of 5.6 to 10. In the near-
infrared
J band it has a
magnitude of -1.7,
[4] is the 7th brightest star in the night sky, and is even brighter than
Sirius .
Water and dust masers
The star also shows signs of intense water emissions, indicative of the presence of a wide disk of dust and
water vapour .
[9] Such emissions cover a zone spanning between 10.7
Astronomical Units (within
Saturn 's orbital zone) and 1.2
parsecs (or nearly 247,500
Astronomical Units , as far away as the
Oort Cloud in
Solar System ).
References
^
"Download Data" . aavso.org . AAVSO. Retrieved 1 October 2021 .
^
"GCVS Query=W Hya" .
General Catalogue of Variable Stars @
Sternberg Astronomical Institute, Moscow, Russia . Retrieved 2012-08-22 .
^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S . 1 .
Bibcode :
2009yCat....102025S .
^
a
b
"V* W Hya" . SIMBAD Astronomical Database. Retrieved 2012-08-21 .
^ Vlemmings, W. H. T.; Van Langevelde, H. J.; Diamond, P. J.; Habing, H. J.; Schilizzi, R. T. (2003). "VLBI astrometry of circumstellar OH masers: Proper motions and parallaxes of four AGB stars". Astronomy & Astrophysics . 407 : 213–224.
arXiv :
astro-ph/0305405 .
Bibcode :
2003A&A...407..213V .
doi :
10.1051/0004-6361:20030766 .
S2CID
11505142 .
^
a
b McDonald, I.; De Beck, E.; Zijlstra, A. A.; Lagadec, E. (2018). "Pulsation-triggered dust production by asymptotic giant branch stars". Monthly Notices of the Royal Astronomical Society . 481 (4): 4984.
arXiv :
1809.07965 .
Bibcode :
2018MNRAS.481.4984M .
doi :
10.1093/mnras/sty2607 .
S2CID
118969263 .
^
a
b De Beck, E.; Decin, L.; De Koter, A.; Justtanont, K.; Verhoelst, T.; Kemper, F.; Menten, K. M. (2010). "Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles. II. CO line survey of evolved stars: derivation of mass-loss rate formulae".
Astronomy and Astrophysics . 523 : A18.
arXiv :
1008.1083 .
Bibcode :
2010A&A...523A..18D .
doi :
10.1051/0004-6361/200913771 .
S2CID
16131273 . A18.
^ Zubko, Viktor; Li, Di; Lim, Tanya; Feuchtgruber, Helmut; Harwit, Martin (2004). "Observations of Water Vapor Outflow from NML Cygnus". The Astrophysical Journal . 610 (1): 427–435.
arXiv :
astro-ph/0405044 .
Bibcode :
2004ApJ...610..427Z .
doi :
10.1086/421700 .
S2CID
14352419 .
^
a
b Zubko & Elitzur, Moshe (2000). "Water and Dust Emission from W Hydrae".
The Astrophysical Journal . 544 (2): 137–140.
arXiv :
astro-ph/0009440 .
Bibcode :
2000ApJ...544L.137Z .
doi :
10.1086/317317 .
S2CID
17702515 .
External links