Peter 433

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Star
gliese 433
Artist's impression of Gliese 433 with the planet Gliese 433 b in the foreground
Artist's impression of Gliese 433 with the planet Gliese 433 b in the foreground
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation Water snake
Right ascension 11 h 35 m 26.95 s
declination -3232 ° 23.8952 ′
Apparent brightness 9.83 mag
Typing
Known exoplanets 2
B − V color index 1.51 
U − B color index 1.17 
R − I index 0.90 
Spectral class M1.5
Astrometry
Radial velocity 17.97 km / s
parallax 112.58  mas
distance 29.5 ± 0.5  ly
9.0 ± 0.1  pc
Visual absolute brightness M vis 9.61 likes
Proper movement 
Rec. Share: −72.51  mas / a
Dec. portion: −851.92  mas / a
Physical Properties
Dimensions 0.48  M ☉
Luminosity

0.034  L ☉

Effective temperature 3,600  K
Metallicity [Fe / H] −0.22
Other names
and catalog entries
Cordoba Survey CD 31 9113
Gliese catalog FY 433 [1]
Hipparcos catalog HIP 56528 [2]
SAO catalog SAO 202602 [3]
Tycho catalog TYC 7220-1321-1 [4]Template: Infobox star / maintenance / specification of the TYC catalog
2MASS catalog 2MASS J11352695-3232232 [5]
Other names LHS 2429, LTT 4290, NLTT 27914

Gliese 433 is a red dwarf in the constellation Hydra , which is about 29.5 light-years from the sun away. The star has a planetary system with at least one confirmed exoplanet . The possible existence of another was published in 2014.

properties

Gliese 433 has only a little less than half the mass of the sun . Its luminosity is just 3.4% of the sun's luminosity . The star's activity is less than half that of other red dwarfs with the same luminosity.

Planetary system

As early as 1997, based on data from the astrometry satellite Hipparcos, a companion for Gliese 433 was suggested, which should be a brown dwarf . This should have a mass of 30 Jupiter and orbit the star in approximately 500 days. Later radial velocity measurements did not confirm this companion.

Based on measurements with the échelle spectrograph HARPS of the ESO was announced the discovery of 32 exoplanets 19 October of 2009. Among them was also a planet around Gliese 433. It was given the name Gliese 433 b and, according to a publication in 2011, should have a minimum mass of 6 Earth masses and orbit its central star once every 7.2 days. A 2013 study classified this planet with a minimum mass of 5.8 Earth masses in the category of super-earths . At a distance of 0.058 AU from the star, Gliese 433 b receives about ten times the radiation energy as the earth receives from the sun.

Another team of astronomers published the confirmation of the existence of Gliese 433 b in 2014 as well as the possible existence of a further outward orbiting planet, Gliese 433 c . This has a minimum mass of 45 earth masses and takes about 3400 days to circle Gliese 433.

Planetary system of Gliese 433
Planet
(by distance from the star) 		Discovery
(year) 		Mass
(in M ♃ ) 		Cycle time
(in days) 		Major semi-axis
(in AU ) 		eccentricity
Gliese 433 b 2009 0.01667 +0.00629−0.00597 7.3697 +0.0034−0.0036 0.06 + 0.004−0.008 0.05 +0.16−0.05
Gliese 433 c 2012 0.14 3693.0 ± 253.0 3.6 0.17 ± 0.09

Individual evidence

  1. ↑ a b c d e SIMBAD: Gliese 433. Accessed June 14, 2015 .
  2. ↑ a b c d e VizieR: GJ 433. Accessed June 14, 2015 .
  3. ↑ a b c d e f g h Delfosse et al .: The HARPS search for southern extra-solar planets XXXV. Super-Earths around the M-dwarf neighbors Gl433 and Gl667C . arxiv : 1202.2467 .
  4. ↑ Bernstein, H.-H .: Astrometric Indications of Brown Dwarfs based on Hipparcos Data. Retrieved June 14, 2015 .
  5. ^ European Southern Observatory: 32 New Exoplanets Found. Retrieved June 14, 2015 .
  6. ↑ Bonfils, X .; Delfosse, X .; Udry, S .; Forveille, T .; Mayor, M .; Perrier, C .; Bouchy, F .; Gillon, M .; Lovis, C .; Pepe, F .; Queloz, D .; Santos, NC; Ségransan, D .; Bertaux, J.-L .: The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample . arxiv : 1111.5019 .
  7. ↑ a b Tuomi et al .: Bayesian search for low-mass planets around nearby M dwarfs. Estimates for occurrence rate based on global detectability statistics . arxiv : 1403.0430 .
  8. ^ The Extrasolar Planets Encyclopaedia: Planet GJ 433 b. Retrieved June 14, 2015 .
  9. ^ The Extrasolar Planets Encyclopaedia: Planet GJ 433 c. Retrieved June 14, 2015 .

Web links