In a landmark discovery, an international team of Chinese and German scientists has identified Kepler-725c – an Earth-sized planet orbiting within the habitable zone of a sun-like star 2,472 light-years away. Published in Nature Astronomy, the findings showcase a novel application of the Transit Timing Variation (TTV) method, offering new pathways in the search for extraterrestrial life.
The planet, with 10 times Earth's mass, completes its orbit every 207.5 days around Kepler-725, a star system resembling our sun in temperature and brightness. Researchers detected subtle gravitational tugs on neighboring gas giant Kepler-725b, using timing irregularities to infer Kepler-725c's presence without direct observation.
"This demonstrates TTV's potential to uncover low-mass planets in habitable zones," said lead researcher Sun Leilei of the Chinese Academy of Sciences' Yunnan Observatories. While liquid water could theoretically exist due to the planet's position, team leader Gu Shenghong emphasized further studies are needed to assess biological potential.
The collaboration involved institutions from the Chinese mainland, including Xi'an Jiaotong-Liverpool University and the Nanjing Institute of Astronomical Optics and Technology, alongside Germany's Hamburg Observatory. The breakthrough highlights growing global partnerships in space exploration and reinforces Asia's expanding role in cutting-edge astrophysical research.
