Gliese 649
Encyclopedia
Gliese 649 is a red dwarf star in the constellation of Hercules
Hercules
Hercules is the Roman name for Greek demigod Heracles, son of Zeus , and the mortal Alcmene...

, located roughly 34 light years from Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

. The star has been found to host an extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...

.

A planetary companion

According to Johnson et al. (2009) a Saturn-mass planet has been detected around the red dwarf star. It yields 32.8% of Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...

's mass and is located 1.15 astronomical unit
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

s from its star in eccentric orbit (e=0.3). Assuming a luminosity of 4.5% that of Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

, the habitable zone
Habitable zone
In astronomy and astrobiology, a habitable zone is an umbrella term for regions that are considered favourable to life. The concept is inferred from the empirical study of conditions favourable for Life on Earth...

 is located at 0.21 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

s, thus the planet should be as cold as if it were located at 5.5 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

s from a Solar-like star. Also accounting different periastron and apastron positions of 0.8 and 1.49 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

s respectively, the planet could likely show seasonal temperature changes.

See also

  • Gliese 317
    Gliese 317
    Gliese 317 is a red dwarf star approximately 50 light-years away in the constellation of Pyxis. The star has an apparent magnitude of 12, an absolute magnitude of 12.2, and corresponding to visual luminosity of 0.1% Sun...

  • Gliese 849
    Gliese 849
    |- style="background-color: #A0B0FF;" colspan="3"| Planet|- bgcolor="#FFFAFA"| Gliese 849b || Gliese 849 is a red dwarf star approximately 29 light years away in the constellation of Aquarius.-Planetary system:...

  • List of extrasolar planets
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