A nearby red dwarf star has a solar system of four planets, one in the habitable zone
According to a new analysis of new data, astronomers now think the nearby red dwarf star GJ 887, only about 11 light years away, not only has a solar system of four planets, one of those planets is is a super-Earth orbiting the star in the habitable zone.
From the abstract:
With the Bayesian analysis, we confirmed a four-planet model, including the two previously known planets at periods of 9.2619 ± 0.0005 d and 21.784 ± 0.004 d, as well as two newly confirmed exoplanets: an Earth-mass planet, with a 4.42490 ± 0.00014 d period and a sub-meter-per-second amplitude, and a super-Earth with a 50.77 ± 0.05 d period located in the habitable zone (HZ). This super-Earth is the second closest planet in the HZ, after Proxima Cen b.
The super-Earth has a mass estimated to be anywhere from two to ten times that of Earth, so if any life could exist on it that life would have to be adapted for an extremely strong gravitational field. The star itself appears to be relatively benign for an M dwarf, having a “low level of magnetic activity”, though it does exhibit some flaring that could pose a threat to the development of life on the planet.
Unfortunately, this system is not aligned in a way to allow transits of these planets across the face of the star, so these conclusions are based on gravitational wobbles of the star analyzed by computer modeling. Lots of uncertainty. The scientists hope that direct observations of the planet by future space telescopes will reduce these uncertainties. At the moment, the proposed privately-funded Lazuli optical orbiting telescope has the best chance of doing this work, but it isn’t expected to launch before the end of the decade. It will have a 3.1 meter primary mirror, larger than Hubble’s 2.4 meter mirror.
It is a so far very slow news day in space.
According to a new analysis of new data, astronomers now think the nearby red dwarf star GJ 887, only about 11 light years away, not only has a solar system of four planets, one of those planets is is a super-Earth orbiting the star in the habitable zone.
From the abstract:
With the Bayesian analysis, we confirmed a four-planet model, including the two previously known planets at periods of 9.2619 ± 0.0005 d and 21.784 ± 0.004 d, as well as two newly confirmed exoplanets: an Earth-mass planet, with a 4.42490 ± 0.00014 d period and a sub-meter-per-second amplitude, and a super-Earth with a 50.77 ± 0.05 d period located in the habitable zone (HZ). This super-Earth is the second closest planet in the HZ, after Proxima Cen b.
The super-Earth has a mass estimated to be anywhere from two to ten times that of Earth, so if any life could exist on it that life would have to be adapted for an extremely strong gravitational field. The star itself appears to be relatively benign for an M dwarf, having a “low level of magnetic activity”, though it does exhibit some flaring that could pose a threat to the development of life on the planet.
Unfortunately, this system is not aligned in a way to allow transits of these planets across the face of the star, so these conclusions are based on gravitational wobbles of the star analyzed by computer modeling. Lots of uncertainty. The scientists hope that direct observations of the planet by future space telescopes will reduce these uncertainties. At the moment, the proposed privately-funded Lazuli optical orbiting telescope has the best chance of doing this work, but it isn’t expected to launch before the end of the decade. It will have a 3.1 meter primary mirror, larger than Hubble’s 2.4 meter mirror.
It is a so far very slow news day in space.












