Dubai, United Arab Emirates (CNN)– Discover Astronomy scientists A “super-Earth,” or a world larger than our planet, orbits a star about 137 light-years away.
It is also possible that there is another planet, believed to be similar in size to Earth, orbiting the same star.
The outer “super-Earth”, known as TOI-715b, orbits a red dwarf star that is cooler and smaller than our Sun.
Astronomers discovered the planet using NASA’s TESS mission, or Transiting Exoplanet Survey Satellite.
A detailed study of this discovery was published in January in the journal Monthly Notices of the Royal Astronomical Society.
The researchers found that the planet, which is estimated to be one and a half times the size of our planet, takes a little more than 19 Earth days to complete one orbit around its star.
The habitable zone is usually calculated based on factors such as the size, temperature, and mass of the star, as well as the reflectivity of the planet’s surface.
The study’s lead author, Dr. Georgina Dranfield, a postdoctoral researcher at the School of Physics and Astronomy at the University of Birmingham in the United States, explained that there are large margins of error associated with these factors, which raises questions about whether the planet is actually in the habitable zone.
Astronomers believe that TOI-715b is located in a narrow, more ideal region in the star’s orbit, known as the habitable zone, which is less likely to be affected by margins of error.
“TESS”… planet hunter
Since its launch in 2018, TESS has helped astronomers discover planets around relatively nearby stars using ground-based and space-based observatories.
“This allows us to get a much clearer picture of the diversity of exoplanetary systems orbiting a wide range of stellar types,” Dranfield said.
In order to confirm the existence of a possible second Earth-sized planet, researchers need more successful observations of planetary transits at different wavelengths of light.
If the existence of an Earth-sized planet is confirmed, it will become the smallest planet discovered by TESS in a habitable zone so far.
Searching for Earth-like planets
Red dwarf stars are the most common stars in our galaxy, a number of which host small rocky worlds.
Planets orbiting closer to these smaller, cooler stars could receive enough warmth to be habitable.
But the key question is whether these planets are also close enough to be exposed to stellar flares and radiation, which could erode their atmospheres, evaporate water, and limit their ability to be habitable.
Dransfield said that TOI-715b has only shown a few flares over the past two years, and is not considered active, making it an old star.
In the future, astronomers hope to be able to search for planets orbiting stars more similar to our sun.
This would require the ability to block intense starlight to find faint Earth-sized planets.
