HD 38283 b
| Extrasolar planet | List of extrasolar planets | |
|---|---|---|
| Parent star | ||
| Star | HD 38283 | |
| Constellation | Mensa | |
| Right ascension | (α) | 05h 37m 02s |
| Declination | (δ) | −73° 41′ 58″ |
| Distance | 123 ± 3 ly (37.7 ± 0.9 pc) | |
| Spectral type | F9.5V | |
| Mass | (m) | 1.085 ± 0.02[1] M☉ |
| Temperature | (T) | 5945 ± 100[1] K |
| Metallicity | [Fe/H] | −0.24 ± 0.07[1] |
| Age | 5.4 ± 1.5[1] Gyr | |
| Orbital elements | ||
| Semimajor axis | (a) | 1.02 ± 0.07[1] AU (153 Gm) |
| Periastron | (q) | 0.60 AU (90 Gm) |
| Apastron | (Q) | 1.44 AU (216 Gm) |
| Eccentricity | (e) | 0.41 ± 0.16 |
| Orbital period | (P) | 363.2 ± 1.6[1] d (0.994 y) |
| Orbital speed | (υ) | 29.78 km/s |
| Time of periastron | (T0) | 2450802.6 ± 12[1] JD |
| Physical characteristics | ||
| Minimum mass | (m sin i) | 0.34 ± 0.02[1] MJ |
| Discovery information | ||
| Discovery date | 2011-04-11 | |
| Discoverer(s) | Tinney et al. | |
| Discovery method | Radial velocity | |
| Discovery site | Anglo-Australian Observatory | |
| Discovery status | Published[1] | |
| Database references | ||
| Extrasolar Planets Encyclopaedia | data | |
| SIMBAD | data | |
| Exoplanet Archive | data | |
| Open Exoplanet Catalogue | data | |
HD 38283 b is an extrasolar planet, orbiting the 7th magnitude F-type main-sequence star HD 38283, 123 light years away in the constellation Mensa. It is a Saturn-like planet orbiting at Earth-like distance in the middle of its habitable zone. But its eccentricity is 0.41, much higher than the Earth's eccentricity of 0.017. The planet's distance ranges from about 0.60 AU (closer to its star than Venus is to the Sun) and 1.44 AU (nearly as distant from its star as Mars is to the Sun). This planet takes 363.2 days to orbit the star, just two days shy of the Earth's orbital period of 365.256366 days. Its mass is one-thirds that of Jupiter but its size and density are not known. Since inclination is not known, its actual mass is unknown, either slightly greater or much greater than its lower limit.
This planet may have Earth-like moons with bodies of water and possibly life. But giving the planet's high eccentricity, life on the moons may not evolve as well as those on Earth. From the surface of the moon, ones may see parent planet in the sky about half of the times with different phases just like the Moon seen from Earth, as well as other moons. If this planet has rings nearly as prominent as Saturn's, then the rings can be seen surrounding the planet, making this scenery even more amazing.
HD 38283 b was discovered on 11 April 2011 using the radial velocity technique using the Anglo-Australian Telescope (AAT). This method uses to look for planets by watching the star periodically wobble caused by the gravitational tug of the orbiting planets.[1]
