Gliese 581
At least four planets are believed to be orbiting Gliese 581. Gliese 581 b, approximately Neptune-sized.
Interstellar
Interstellar TravelMilky Way
Solar System
Planets
Constellations
Solar Systems
The Star
The name Gliese 581 refers to the catalog number from the Gliese Catalogue of Nearby Stars. Other names of this star include BD-07° 4003 (BD catalogue, first known publication) and HO Librae (variable star designation). It does not have an individual name such as Sirius or Procyon. The star is a red dwarf with spectral type M3V, located 20.3 light years away from Earth. It is located about two degrees north of Beta Librae, the brightest star in the constellation Libra. Its mass is estimated to be approximately a third that of the Sun, and it is the 87th closest known star system to the SunPlanetary System Summary
At least four planets are believed to be orbiting Gliese 581. Gliese 581 b, approximately Neptune-sized, was discovered in August 2005 and was the fifth planet to be discovered around a red dwarf star. This inner planet is at least 16 times as massive as Earth (similar to Neptune's mass) and completes a full orbit of Gliese 581 in only 5.4 days |
|
Gliese 581 b
 |
4gliese-581 b Statistics
|
|
Orbit and massGliese 581 b is at minimum about 16 times the Earth's mass, similar to Neptune's mass. It does not transit its star, implying that its inclination is less than 88.1 degrees.[3] Dynamical simulations of the Gliese 581 system assuming that the orbits of the four planets are coplanar show that the system becomes unstable if its component masses exceed 1.6 – 2 times their minimum masses. This is primarily due to the close separation between planets b and e. For Gliese 581 b, the upper mass limit is 30.4 Earth masses, or about 77% more massive than Neptune.[1] It is rather close to Gliese 581 and completes a full orbit in only 5.4 days at a mean distance of about 6 million kilometres (0.041 AU). By comparison, Mercury is at a distance of 58 million kilometres (0.387 AU) and completes an orbit in 88 days. |
Gliese 581 c
Gliese 581 c Statistics
Parent star |
|
| Star: | Gliese 581 |
| Constellation | Libra |
Orbital elements |
|
| Semimajor axis: | 0.07[1] AU (11 Gm) |
| Eccentricity: | 0.17 ± 0.07 |
| Orbital Period: | 12.9292 ± 0.0047[1] d (0.0353976 y) |
| Orbital speed: | 62 km/s |
| Inclination: | ==30[1]° |
| Time of periastron: | 2,454,699.42 ± 0.87 |
| Semi-amplitude: | 3.24 ± 0.24 m/s |
Physical characteristics |
|
| Minimum mass: | (m sin i) 5.36[1] M? |
Discovery information |
|
| Year Discovered: | April 4, 2007 |
| Detection Method: | Radial velocity |
| Discovered By: | Stéphane Udry et al. |
Gliese 581 d
Gliese 581 d
Parent star |
|
| Star: | Gliese 581 |
| Constellation | Libra |
Orbital elements |
|
| Semimajor axis: | 0.22 AU (33 Gm) |
| Eccentricity: | 0.38 ± 0.09[ |
| Orbital Period: | 66.80 ± 0.14[1] d (0.1829 y) |
| Orbital speed: | 36 km/s |
| Inclination: | =30° |
| Time of periastron: | 2,454,603.0 ± 2.2 JD |
Physical characteristics |
|
| Minimum mass: | (m sin i) 7.09 M? |
Discovery information |
|
| Year Discovered: | 24 April 2007 |
| Detection Method: | Radial velocity |
| Discovered By: | Udry et al. |
Gliese 581 e
Gliese 581 e Statistics
Parent star |
|
| Star: | Gliese 581 |
| Constellation | Libra |
Orbital elements |
|
| Semimajor axis: | 0.03 AU (4 Gm) |
| Eccentricity: | 0 |
| Orbital Period: | 3.14942 ± 0.00045 d (0.0086225 y) (75.586 h) |
| Orbital speed: | 106 km/s |
| Inclination: | =30° |
| Time of periastron: | 2,454,716.80 ± 0.01 JD |
Physical characteristics |
|
| Minimum mass: | (m sin i) 1.94 M? |
Discovery information |
|
| Year Discovered: | 21 April 2009 |
| Detection Method: | Radial velocity |
| Discovered By: | Mayor et al. |
Planetary Orbits Around Gliese 581
Greeting cards, poetry, santa letters, gifts books, and more!
