Could Alien Life Exist on Newly Found Super-Earth in Sun-Like Star’s Habitable Zone?

Discovery of Kepler-725c: A Super-Earth in the Habitable Zone

The age-old question of whether humanity is alone in the universe has taken an exciting turn. Chinese astronomers announced the discovery of Kepler-725c, a “super-Earth” located 2,400 light-years away, raising hopes of extraterrestrial life. This rocky planet, with 10 times Earth’s mass, orbits within the “habitable zone” of its star—a region where liquid water, and thus life, could exist.

[Image: Artist’s depiction of Kepler-725c, a watery world with a rocky surface and oceans.]

Conditions for Life
Kepler-725c completes an orbit every 207.5 days and receives 1.4 times more solar radiation than Earth. Despite higher radiation, its position in the habitable zone suggests temperatures suitable for liquid water. Researchers from the Chinese Academy of Sciences propose two possibilities: a water-covered “Hycean” world with a hydrogen-rich atmosphere or an Earth-like planet with oceans and exposed land. Its star, Kepler-725, is younger than our Sun at 1.6 billion years old, and the system includes another gas giant planet, Kepler-725b, with a tight 39.6-day orbit.

Breakthrough Detection Method
The discovery marks the first time the Transit Timing Variation (TTV) method identified a habitable-zone planet around a Sun-like star. Unlike traditional techniques that detect dips in starlight (transit) or gravitational wobbles (radial velocity), TTV analyzes subtle timing irregularities in a known planet’s orbit caused by neighboring celestial bodies. By studying Kepler-725b’s orbit, researchers inferred Kepler-725c’s mass and trajectory.

[Image: Illustration of the TTV method, showing planets influencing each other’s orbits.]

Hycean Worlds: A New Frontier
Kepler-725c may belong to the hypothetical “Hycean” class—planets with vast oceans beneath hydrogen atmospheres. Such worlds could host microbial life, even under extreme conditions. While Hyceans remain theoretical, their potential to broaden the search for life has energized astronomers.

K2-18b: Another Candidate for Alien Life
This discovery follows recent insights into K2-18b, a super-Earth 120 light-years away. Observations from the James Webb Space Telescope detected methane, carbon dioxide, and tentative signs of dimethyl sulfide (DMS)—a compound on Earth produced only by marine life. Though not yet confirmed, DMS hints at biological activity, with concentrations thousands of times higher than Earth’s.

[Image: Artist’s impression of K2-18b, a hycean world with possible ocean-covered surface.]

Cautious Optimism
While both Kepler-725c and K2-18b spark excitement, scientists emphasize caution. Detecting life requires crossing the “five-sigma” statistical threshold, a benchmark K2-18b’s data hasn’t yet met. Further JWST observations could resolve uncertainties, but for now, these discoveries highlight the rapid progress in exoplanet research.

Why It Matters
Since the first exoplanet discovery in 1995, over 5,000 worlds have been cataloged. Kepler-725c and K2-18b represent a shift toward identifying not just planets, but those capable of hosting life. As detection methods like TTV advance, the odds of answering “Are we alone?” grow ever stronger.

[Image: The Kepler Space Telescope, which pioneered exoplanet hunting before retiring in 2018.]

In the quest for alien life, each discovery brings us closer to rewriting one of humanity’s oldest mysteries.