Searching for planet B
Finding a livable world that is similar to Earth is one of the most intriguing objectives of extraterrestrial study.
Photo: An artist’s depiction of a rocky exoplanet orbiting a red dwarf star./NASA/Daniel Rutter
More than 5,000 exoplanets discovered
Astronomers have long been interested in finding other habitable planets. And though they have discovered more than 5,000 exoplanets, less than 200 are rocky or terrestrial and only about 1.5% have similar masses to Earth.
Photo: NASA/JPL-Caltech
Only about 12 exoplanets potentially have water
Furthermore, only about a dozen
of all discovered exoplanets orbit their stars in the so-called 'habitable zone': just the right distance from their star that water can pool as a liquid on the planet's surface.
Wolf 1069 b: promising exoplanet discovered
What’s promising about an exoplanet, named Wolf 1069 b, that was discovered last year, is that it has all of the aforementioned characteristics.
Orbits a red dwarf star
The name of the exoplanet is Wolf 1069 ‘b’ because it orbits a red dwarf star called Wolf 1069 in the constellation Cygnus (pictured).
Photo: ESA/PACS/SPIRE/Martin Hennemann & Frederique Motte, Laboratoire AIM Paris-Saclay
A prime candidate for water
Wolf 1069 b also orbits in its star’s habitable zone, making it a prime candidate for liquid water to exist on its surface.
Photo: Matt Hardy/Unsplash
Similar mass and size to Earth
The Earth-like planet is only 31 light-years away from us and has a very similar mass and size to those of planet Earth.
Tidally locked with its host star
Wolf 1069 b is tidally locked to Wolf 1069 (its host star), in the same way that our Moon is tidally locked to Earth.
Day-side and night-side
This means that the same side of the exoplanet always faces its star, so its day-side and night-side remain the same.
Only the day-side would be habitable
This is also a peculiar characteristic. More so, since only the day-side of the planet would be habitable, as explained by the team of astronomers who found Wolf 1069 b in the Calar Alto Observatory in Spain.
Red dwarfs are sources of high-energy radiation
Even though red dwarfs are notorious for violent UV flare that can strip a planet away from its atmosphere, Wolf 1069 is an exception.
Wolf 1069 b is colder than Earth
Since Wolf 1069 is so much smaller and less energetic than our Sun, its habitable zone is much closer and the planet receives less energy than Earth does from the Sun; only about 65%, which also means that it’s colder than Earth.
Photo: Ivana Cajina/Unsplash
A lack of intense radiation
In fact, the team behind the discovery believe Wolf 1069 b could have retained much of its atmosphere due to a lack of any apparent stellar activity or intense radiation from the host star.
A good target to search for signs of life
Therefore, the planet is one of a very small number of promising targets to look for biosignatures and signs of habitability.
Another 10 years to have a detailed study of Wolf 1069b
However, astronomer Diana Kossakowski, lead author on the research, told the BBC that they would possibly have to wait another ten years to do further studies into potential biomarkers or habitability on Wolf 1069 b.
A noteworthy discovery
Nonetheless, in the paper where they reported these findings, researchers describe Wolf 1069 b as a “noteworthy discovery that will allow further exploration into the habitability of Earth-mass planets around M dwarfs, as well as case study in testing planetary formation theories.”