synonymGliese 581(Gliese 581) generally refers to Gliese 581
Gliese 581, located 2 degrees north of Beta LibraRed dwarf, about 20.4 light years (193.9 trillion kilometers) from the earth, spectral type M2.5V,Apparent magnitudeApproximately+10.56.
In all knownStellar systemIn, Gliese 581 is the 87th star near the sun, and its mass is estimated to be about 1/3 of the sun.
Gliese 581gIs a circleRed dwarfA planet of Gliese 581, located inPlanetary systemUnified livable area with stableatmosphereThe surface can maintain liquid lakes and rivers.According to the latest observation results in April 2009, another planetGliese 581dAlso located inHabitable zoneInside, and according to thegreenhouse effectIt is estimated that the planet may haveLiquid water。Researchers believe that the planet may have "deep and huge oceans".It is aSuper EarthOr mini Neptune, aOcean planet。The planetary system has already included six planets, the number of which is Gliese 581 b~Gliese 581 g, and each new planet will be added with letters in order as a mark.The planetary system andsolar systemVery similar, the orbits of planets are mostly close to perfect circle andEccentricityMost are very low.The biggest difference is that most of the planets have very close orbitsPrimary star, so many planets are concentrated in a smaller range than the earth to the sun, and the mass is more than the earth, which is of great significance for the formation and evolution of stars and planets.
In September 2010,University of California, Santa CruzA team led by scientists announced the discovery of a new home 20 light years away -“Second Earth”Gliese 581g.[1]On September 29, astronomers announced their discoveryGliese 581fAndGliese 581g, both run on approximately circular orbits.581gTidal locking The relationship is always facing the stars with the same side. It is speculated that the temperature at the junction of day and night may be similar to that of the earth, and there may be liquid water.
However, some astronomers pointed out that there is no credible signal of any planet in the habitable area of Gliese 581, and the existence of Gliese 581g cannot be confirmed.
British astronomers based on HARPSobserved data It is believed that Gliese 581 is most suitable for the existence of five planets, whose cycle times around the stars are 3, 5, 13, 67 and 400 days, respectivelyRevolution period36 day Gliese 581g does not exist.According to the high resolution fly eye of the United Statesdetector(HiRes) Research shows that the probability error of Gliese 581 owning six planets is 99.9978%. The latest discovery that the previous HARPS had Gliese 581 d in 2007 also proves that Gliese 581 g does not exist.HARPS has recently discovered 50 new exoplanets, of which 16 are super Earths, including oneHD 85512b35 light years away, in the habitable area, the possible temperature isCelsius45 degrees. It matchesGliese 581dIt is currently two planets with solid evidence suitable for human survival.
The galaxy where Gliese 581 is located
In 2011, fromCanadaExperts in astrostatistics“Bayesian analysis method”Once again, it proves that the star does not exist - the model reports that no planet in the same system is locatedLivable zoneHowever, the possibility that the conclusion "Gliese 581g exists" is wrong is 99.9978%.In 2014, the United StatesPennsylvania State UniversityScientists point out that in fact, Gliese 581g does not exist, nor does another planet in the planetary system, Gliese 581d, which was discovered earlier.Gliese 581d was once considered as a cold planet with a relatively large orbit, but the greenhouse effect also allows it to support life.Now, it will be deleted from the system directory together with "Brother".[1]
Although the possibility of the existence of Gliese 581g is very small, and despite a large number of facts, mostterrestrial planetAnd the solar systemexternal galaxyAre very different from our solar system, but astronomers still believe thatDiscovery JourneyThere is a bigger prize waiting for us - that is, a planet with the same size and temperature as our Earth.Gliese 581g may be just a cosmic illusion, but the habitable planet is not just an astronomical fairy tale.There is no doubt that our earth is by no means unique and accidental. There must be our "brothers" outside the earth.[1]
