14 Herculis b
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Exoplanet 14 Herculis b |
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| artist's impression | |
| Constellation | Hercules |
| Position equinox : J2000.0 |
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| Right ascension | 16h 10m 24.31383s |
| declination | + 43 ° 49 ′ 03.5264 ″ |
| Orbit data | |
| Central star | 14 Herculis |
| Major semi-axis | 2.77 ± 0.05 AU |
| eccentricity | 0.369 ± 0.005 |
| Period of circulation | 1773.4 ± 2.5 d |
| Further data | |
| Dimensions | 4.64 ± 0.19 |
| distance | 18.1 pc |
| method | Radial velocity method |
| history | |
| Date of discovery | 1998 |
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14 Herculis b is an exoplanet orbiting the main sequence star 14 Herculis . Due to its high mass , it is assumed that it is a gas planet . At the time of its discovery in 1998 , it was the exoplanet with the largest orbital period, but other extrasolar planets with longer orbital times have now been detected. In 2005 a second planet in the 14 Herculis system was proposed with 14 Herculis c , but this is not considered confirmed.
discovery
The planet was detected indirectly by periodic frequency shifts of the central star ( radial velocity method ) with the ELODIE spectrograph in southern France. The discovery was announced at the 4th "Protostars and Planets" meeting by Michel Mayor's working group in 1998.
Track properties
The planet orbits its star at a distance of approximately 2.77 astronomical units every 1773.4 days . Its path shows a high eccentricity of almost 37%.
Physical Properties
14 Herculis b has a minimum mass of approx. 1500 earth masses or 4.64 masses of Jupiter. Due to the uncertain inclination of the orbit, the exact mass cannot currently be determined with certainty. Astrometric measurements of the Hipparcos satellite, according to which the orbital inclination is 155.3 ° (which would have meant an actual mass of more than 11 Jupiter's masses) were later disqualified as insufficiently accurate. Currently the value for the mass still applies.
Direct observation
Because of its great distance to its star and the short distance of the 14 Hercules system to the sun, it would be a promising candidate for direct observation.
Web links
swell
- Wittenmyer, RA, Endl, M., Cochran, WD: Long-Period Objects in the Extrasolar Planetary Systems 47 Ursae Majoris and 14 Herculis . In: The Astrophysical Journal . 654, No. 1, 2007, pp. 625-632. bibcode : 2007ApJ ... 654..625W . doi : 10.1086 / 509110 .