This 'super-Earth' orbits its star in 647 days like Mars
What's the story
Astronomers have discovered a 'super-Earth' that orbits a Sun-like star 20 light-years away from our planet.
Dubbed HD 20794 d, it is a part of a tri-planet system orbiting the star HD 20794.
With an orbit of 647 days, HD 20794 d is similar to Mars in our solar system. However, its orbit around the star is highly elliptical.
This feature causes extreme temperature variations on the planet, swinging from intense heat to deep freeze every 300 days.
Habitability
A potential haven for life
At its closest to the star, it resembles Venus's distance from our Sun and at its farthest, it's twice as far as Earth is from Sun.
Despite its orbit, HD 20794 d remains in the habitable zone for a good part of its year. This is where liquid water could exist under right atmospheric conditions.
The planet is six times more massive than Earth and might be rocky.
These features would allow us to study it and investigate potential habitability.
Discovery process
Confirmation of HD 20794 d's existence
To confirm the existence of HD 20794 d, a global team of scientists examined more than two decades of data from the HARPS and ESPRESSO spectrographs in Chile.
These instruments measure the subtle shifts in the star's light spectrum due to the gravitational pull from orbiting planets.
Led by Nicola Nari, the team worked hard to separate genuine planetary signals from stellar activity.
Astrobiology research
A prime candidate for future studies
HD 20794 d makes an exciting target for studies in the future, especially with upcoming space-based telescopes such as NASA's Habitable Worlds Observatory.
Its closeness to Earth and relatively stable stellar environment makes it an ideal candidate for examining atmospheres and searching for any signs of life.
The planet's unique orbit and potential to have liquid water raise important questions about adaptability of life under extreme conditions, making it a prime subject in astrobiology research.