A global group of scientists has just located a celestial body with features very similar to those of our planet, receiving the name HD 137010 b. This star follows its trajectory around a K-type orange dwarf star, located approximately 146 light-years from the Solar System, in the Libra constellation region. The find was made possible thanks to the review of old records captured in 2017 by the K2 phase of the Kepler space telescope, operated by NASA.
The possible new world has a diameter only 6% larger than the Earth’s globe and takes approximately 355 days to complete one revolution around its sun. Such characteristics place the find in a very select group of stars that share proportions and annual cycles almost identical to ours. Experts point out that the amount of light and stellar energy that reaches the surface of the object is equivalent to 29% of that we receive daily.
Mathematical evaluations indicate that there is a 50% chance that HD 137010 b is positioned exactly in the so-called habitable zone of its system. This specific orbital band is what guarantees the ideal temperature for water to remain in a liquid state on rocky soil, a fundamental condition for life as we know it.
How ancient records from the Kepler telescope revealed the new star
The first indication of the existence of HD 137010 b came about thanks to the efforts of volunteer enthusiasts participating in the Planet Hunters citizen science program. The group noticed a unique light block that lasted exactly 10 hours during the 15th observation campaign of the K2 mission. This slight drop in the brightness of the main star was the trigger to suggest that an object of modest proportions had crossed the equipment’s line of sight.
Confirmation of the signal was carried out by a team led by researcher Alexander Venner, linked to the University of Southern Queensland, in Australia, with the results published in the Astrophysical Journal Letters. The academics applied complex statistical models to calculate the star’s route, taking into account that there were no other transits recorded in the database. As the central star has a visual magnitude of 10.1, being considered quite bright by astronomical standards, future monitoring becomes much more viable.
Identifying a planet from a single pass in front of its star is an immense technical hurdle, but it proves the immense potential of combing through old archives. The Kepler observatory has monitored thousands of star systems over its lifetime, and isolated events like this are the key to discovering unusual worlds that have very long years.
The exact location of HD 137010 b in the habitability range
The ideal distance for life changes according to the intensity of each star, and in the case of K dwarfs, this safe region is closer to what we observe in the Solar System. The newly discovered celestial body travels an average distance of 0.88 astronomical units from its sun. This specific distance positions it almost at the outer limit of the area considered conservatively habitable.
Preliminary surveys suggest that the radiation received is sufficient to prevent total freezing, provided favorable atmospheric conditions exist. However, the reduced brightness of the orange dwarf generates a very low natural thermal balance. Computer simulations indicate that, if the planet did not have a robust greenhouse effect, thermometers would read an average of -68°C on the surface.
- The existence of a thick gaseous envelope would be capable of retaining heat and creating a milder climate.
- The small size and expected density strongly indicate that it is a world made of rocks.
- If there are no greenhouse gases, the scenario would be an icy desert, closely resembling the climate on Mars.
Even with the forecast of extremely harsh weather, these variables do not remove the object from the list of most promising candidates found so far.
Differences between the new find and other worlds already mapped by science
HD 137010 b immediately stands out in a catalog of thousands of exoplanets for combining a size similar to ours with a long orbit around a star similar to the Sun. Unlike most worlds found near red dwarfs, it orbits a much calmer star free from violent explosions. Bodies like Kepler-452b even have similar trajectories, but they orbit stars so distant and faint that detailed analysis becomes almost impossible.
Finding rocky spheres in the habitable zone is an absolute rarity, with fewer than a dozen candidates with strong evidence. The famous TRAPPIST-1 system is home to several of them, but they all revolve too quickly around an ultra-cool dwarf, while Proxima Centauri b suffers from devastating solar storms. Furthermore, K dwarf stars like the one on the new planet live between 15 and 45 billion years, offering a much longer stability time for the development of any complex chemistry than our own Sun, which will only live for about 10 billion years.
Being situated a mere 146 light-years away makes HD 137010 b a perfectly accessible target for current and next generation telescopes. The intense brightness of its mother star makes it possible for observatories installed on Earth to calculate the planet’s mass using the radial velocity technique.
The technical challenges of confirming a planet with just one pass
The transit technique works by measuring the temporary drop in a star’s light when an object passes directly in front of it. In the HD 137010 b scenario, the equipment recorded only a single blockage during three entire months of image capture. This solitary event is what prevents scientists from putting the hammer down immediately, as science requires multiple passes to confirm the annual cycle.
To overcome the lack of data, experts resorted to Bayesian statistics, managing to limit the translation time to between 296 and 555 days. The probability of the geometric alignment strongly suggests that the shadow was caused by a planet, and not by natural fluctuations of the star. False positive hypotheses, such as the eclipse caused by a background binary star system, were completely ruled out due to the lack of variation.