A planet with a mass similar to Earth, probably rocky and with an atmosphere, has been discovered in the habitable zone -suitable for liquid water on the surface- of the red dwarf star Wolf 1069.
“When we analyzed the data from the star Wolf 1069, we discovered a clear, low-amplitude signal from what appears to be a planet about the mass of Earth,” said Diana Kossakowski, an astronomer at the Max Planck Institute for Science. Astronomy, which discovered the new planet within the framework of the Carmenes project, from the Calar Alto Observatory, in Almería.
At 31 light-years from Earth, Wolf 1069 b “orbits the star in 15.6 days at a distance equivalent to one-fifteenth the distance between the Earth and the Sun,” he adds. The results of the study have now been published in the journal Astronomy & Astrophysics.
According to the study, the surface of the dwarf star is relatively cool, so it has a reddish-orange appearance. “As a result, the so-called habitable zone moves inland,” explains Kossakowski.
Despite its short distance to the central star, the planet Wolf 1069 b only receives 65% of the incident radiation that the Earth receives from the Sun. These special conditions make planets around red dwarf stars like Wolf 1069 potentially favorable for life. Furthermore, it is possible that they all share a special property. Its rotation is probably tied to the orbit of its host star. In other words, the star always faces the same side of the planet.
A) Yes, the day is eternal, while on the other side it is always night. This is also the reason why we always look towards the same side of the Moon.
If Wolf 1069 b is assumed to be a bare, rocky planet, the average temperature even on the side facing the star would be only minus 23 degrees Celsius. However, based on existing knowledge, Wolf 1069 b may well have formed an atmosphere.
In this case, its temperature could have risen by up to plus 13 degrees, as computer simulations with climate models show. Under these circumstances, the water would remain liquid and conditions favorable to life could occursince this, as we know it, depends on water.
An atmosphere is not only a precondition for the appearance of life from the climatic point of view. It would also shield Wolf 1069 b from high-energy electromagnetic radiation and particles that would destroy potential biomolecules. The radiation and particles come from interstellar space or from the central star. If the star’s radiation is too intense, it can also destroy a planet’s atmosphere, as happened to Mars. But as a red dwarf, Wolf 1069 emits only relatively weak radiation.
Thus, an atmosphere may have been preserved on the newly discovered planet. It is even possible that the planet has a magnetic field that shields it from charged particles in the stellar wind. Many rocky planets have a liquid core that generates a magnetic field through the dynamo effect, similar to that of planet Earth.