Earth-sized world discovered in rare year-long orbit

The planet, known as HD 137010 b, is slightly larger than Earth and circles its star at a distance similar to the Earth-Sun gap. Because of this, scientists say it may lie near the outer edge of the star’s habitable zone, the region where liquid water could exist if the planet has the right atmosphere.

The discovery comes from a fresh look at data collected by NASA’s Kepler space telescope, which ended its mission in 2018. Even years later, researchers continue to find new planet candidates hidden in the archive. In this case, the signal was seen when the planet passed in front of its star, briefly dimming the light in what astronomers call a transit.

The planet is estimated to be about 6% larger than Earth and follows a roughly 355-day orbit. However, the star it orbits is cooler and dimmer than our Sun. As a result, the planet likely receives less than one third of the energy Earth gets, meaning its surface could be extremely cold. Researchers estimate temperatures could drop to around minus 68 degrees Celsius, making it even colder than Mars.

Despite this, the planet is not ruled out as potentially livable. According to the research team, if HD 137010 b has a thick atmosphere rich in carbon dioxide, it could trap enough heat to allow milder conditions and possibly liquid water. Their models suggest there is a meaningful chance the planet sits within a broader definition of the habitable zone, though there is also a similar chance it lies beyond it.

For now, HD 137010 b remains a planet candidate. Astronomers need to see the transit repeat to confirm that the signal truly comes from a planet. This will be difficult because planets with Earth like orbits pass in front of their stars only rarely. Future observations by NASA’s TESS mission or Europe’s CHEOPS satellite could help confirm its existence.

Earlier, Qazinform News Agency reported that bacteria and viruses evolve differently in space environment.