SCIENCE

Discovery of Earth-Like Exoplanet Gliese 12 b Sparks Excitement

Astronomers have discovered an Earth-like planet with the potential to support human life, located just 40 light-years away. Named Gliese 12 b, this intriguing exoplanet orbits its host star every 12.8 days and is comparable in size to Venus, making it slightly smaller than Earth. This discovery offers a rare opportunity to study a planet with characteristics akin to those of our own world, potentially advancing our understanding of planetary habitability.

A Promising New World

Gliese 12 b’s estimated surface temperature of 42°C is notably lower than most of the approximately 5,000 exoplanets confirmed to date, positioning it as a significant target for further research. The planet orbits a cool red dwarf star, Gliese 12, located in the constellation Pisces. This star is about 27% the size of the Sun and has a surface temperature that is 60% of our Sun’s.

Professor Thomas Wilson from the University of Warwick, who played a key role in confirming Gliese 12 b’s existence using data from NASA’s satellites, expressed his enthusiasm: “This is a really exciting discovery and will help our research into planets similar to Earth. Planets like Gliese 12 b are few and far between, so for us to be able to examine one this closely and learn about its atmosphere and temperature is very rare.”

Potential for Human Survival

While the discovery of Gliese 12 b is thrilling, scientists are still uncertain about the composition of its atmosphere, if it has one at all. Understanding the atmosphere is crucial, as it determines whether the planet can maintain temperatures suitable for liquid water – a key ingredient for life as we know it.

Masayuki Kuzuhara, a project assistant professor at the Astrobiology Centre in Tokyo and co-leader of one of the research teams, noted the significance of this discovery: “We’ve found the nearest, transiting, temperate, Earth-size world located to date. Although we don’t yet know whether it possesses an atmosphere, we’ve been thinking of it as an exo-Venus, with similar size and energy received from its star as our planetary neighbour in the solar system.”

Observations and Future Research

The two research teams, one based in Tokyo and the other led by Shishir Dholakia at the University of Southern Queensland, utilized observations from NASA’s TESS (Transiting Exoplanet Survey Satellite) to identify and study Gliese 12 b. The planet’s proximity to its star – only 7% of the distance between Earth and the Sun – means it receives 1.6 times more energy from its star than Earth does from the Sun.

Red dwarf stars, like Gliese 12, are known for their magnetic activity and frequent powerful X-ray flares, which can impact a planet’s ability to retain an atmosphere. However, preliminary analyses suggest that Gliese 12 does not exhibit extreme behavior, increasing the likelihood that Gliese 12 b could maintain a stable atmosphere.

Shishir Dholakia emphasized the importance of this discovery: “Gliese 12 b represents one of the best targets to study whether Earth-size planets orbiting cool stars can retain their atmospheres, a crucial step to advance our understanding of habitability on planets across our galaxy.”

Looking Ahead

The discovery of Gliese 12 b has been highlighted as a potential target for further investigation by NASA’s £7.5 billion James Webb Space Telescope (JWST). This advanced telescope could provide more detailed observations of the planet’s atmosphere and surface conditions, offering insights into whether it could indeed support life.

Co-author Dr. Vincent Van Eylen from University College London remarked on the planet’s significance: “GJ12b is an incredibly exciting planet because its size is identical to that of Earth. Even though GJ12b is about 15 times closer to its star than Earth is to our Sun, because it orbits such a small star the temperature on the planet may be quite similar to that on Earth.”

The findings from these studies have been published in prominent scientific journals, with the Tokyo team’s research appearing in The Astrophysical Journal Letters and the Dholakia and Palethorpe findings in the Monthly Notices of the Royal Astronomical Society.

As we continue to explore the cosmos, the discovery of Gliese 12 b represents a significant step towards understanding the potential for life on planets beyond our solar system.