HD 181433

HD 181433
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pavo
Right ascension 19h 25m 09.5663s[1]
Declination -66° 28′ 07.671″[1]
Apparent magnitude (V) 8.38[1]
Characteristics
Spectral type K5V[2]
B−V color index 1.04[1]
Astrometry
Radial velocity (Rv) +37.9[1] km/s
Proper motion (μ) RA: –230.60[3] mas/yr
Dec.: 235.37[3] mas/yr
Parallax (π) 37.37 ± 1.13[3] mas
Distance 87 ± 3 ly
(26.8 ± 0.8 pc)
Absolute magnitude (MV) 6.24[note 1]
Other designations
Database references
SIMBAD data
NStED data
Extrasolar Planets
Encyclopaedia		 data

HD 181433 is a star located approximately 87 light-years away[3][note 2] in the constellation of Pavo (the Peacock). According to SIMBAD, it has a stellar classification of K3III-IV,[1] which puts it on the borderline between being a red giant and a subgiant this is inconsistent with its luminosity properties: it has a luminosity of only 0.308 times that of the Sun.[4] Its entry in the Hipparcos catalogue lists a spectral type of K5V,[2] classifying it as a dwarf star. As of 2008, three extrasolar planets are thought to be orbiting within the system.[5] There is currently little information on these planets. The name of this star comes from its identifier in the Henry Draper catalogue.

Contents

Planetary system

Orbiting the star are three planets, the discovery was announced in 2008[6] and the discovery paper was published in 2009.[4] The inner planet has a mass at least 7.5 times that of Earth, and is termed a super-Earth (this classification is based solely on the mass of the planet and should not be taken to imply that the planet could support Earthlike conditions). The middle planet and the outer planet are gas giants. The orbital periods for three planets are 9.3743 days for a 7.56 ME planet, 962 days for a 0.64 MJ planet, and 2172 days for a 0.54 MJ planet.[4]

The HD 181433 system[4]
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity
b ≥0.0238 MJ 0.080 9.3743 ± 0.0019 0.396 ± 0.062
c ≥0.64 MJ 1.76 962 ± 15 0.28 ± 0.02
d ≥0.54 MJ 3.00 2172 ± 158 0.48 ± 0.05

See also

Notes

  1. ^ Calculated from apparent magnitude and parallax (assuming negligible absorption due to interstellar dust): \textstyle M_{\mathrm{V}} = m_{\mathrm{V}} - 5\log_{10} \left(\frac{100}{\mathrm{parallax\ in\ milliarcseconds}}\right)
  2. ^ Calculated from parallax: \textstyle \mathrm{Distance\ in\ parsecs}=\frac{1000}{\mathrm{parallax\ in\ milliarcseconds}}

References

  1. ^ a b c d e f "NLTT 47732 -- High proper-motion star". SIMBAD. http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=hd+181433&NbIdent=1&Radius=10&Radius.unit=arcmin&submit=submit+id. Retrieved 2008-10-02. 
  2. ^ a b ESA (1997). "HIP 95152". The Hipparcos and Tycho Catalogues: The Hipparcos Main Catalogue. http://webviz.u-strasbg.fr/viz-bin/VizieR-S?HIP%2095467. Retrieved 2008-10-02. 
  3. ^ a b c d van Leeuwen, F. (2007). "HIP 95152". Hipparcos, the New Reduction: The Astrometric Catalogue. http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=I/311/hip2&recno=95152. Retrieved 2008-10-02. 
  4. ^ a b c d Bouchy, F.; Mayor, M.; Lovis, C.; Udry, S.; Benz, W.; Bertaux, J.-L.; Delfosse, X.; Mordasini, C.; Pepe, F.; Queloz, D.; Segransan, D. (2009). "The HARPS search for southern extra-solar planets. XVII. Super-Earth and Neptune-mass planets in multiple planet systems HD 47186 and HD 181433". Astronomy and Astrophysics 496 (2): 527–531. Bibcode 2009A&A...496..527B. doi:10.1051/0004-6361:200810669. 
  5. ^ "A Trio of Super-Earths" (Press release). ESO. 2008-06-16. http://www.eso.org/public/outreach/press-rel/pr-2008/pr-19-08.html. Retrieved 2008-10-02. 
  6. ^ "Astronomers find batch of "Super Earths"". BT Yahoo.com. Archived from the original on 2008-06-17. http://web.archive.org/web/20080617232529/http://uk.news.yahoo.com/rtrs/20080616/tsc-uk-space-planets-011ccfa.html. Retrieved 2008-06-16. 

External links

Coordinates: 19h 25m 09.5663s, −66° 28′ 07.671″

HD 181433 system
Stars
HD 181433
Planets