In a groundbreaking revelation, NASA researchers have uncovered a potential treasure trove in our Milky Way galaxy — a “Super Earth” named TOI-715 b, residing comfortably within its host star’s habitable zone. This distant exoplanet, located 137 light years away, has sparked excitement due to its size, location, and the tantalizing possibility of containing water on its surface, a key ingredient for the existence of life.
The discovery was made using NASA’s Transiting Exoplanet Survey Satellite (TESS), a space telescope designed to identify exoplanets by detecting subtle changes in the brightness of stars as planets pass in front of them. TOI-715 b, estimated to be one and a half times wider than Earth, orbits a red dwarf star, a cooler and smaller celestial body compared to our Sun. This unique configuration allows the exoplanet to rest within the star’s habitable zone, where conditions might be suitable for liquid water to exist.
While TOI-715 b has a significantly shorter orbit period (19 days) compared to Earth, which completes an orbit around the Sun in 365 days, the cooler nature of the red dwarf star creates favorable conditions for the potential habitability of the exoplanet.
NASA explained, “These planets make far closer orbits than those around stars like our Sun, but because red dwarfs are smaller and cooler, the planets can crowd closer and still be safely within the star’s habitable zone. The tighter orbits also mean those that cross the faces of their stars – that is, when viewed by our space telescopes – cross far more often.”
Excitement surrounds the possibility of a second, Earth-sized planet in the same system. If confirmed, this potential discovery would mark the smallest habitable-zone planet detected by TESS to date. The hope is that NASA’s upcoming James Webb Telescope might offer a closer examination of TOI-715 b, specifically to determine if it possesses an atmosphere.
NASA emphasized that understanding the planet’s other properties, such as its mass and potential classification as a “water world,” would play a crucial role in assessing the detectability of its atmosphere. A “water world,” characterized by a significant water content, could make the planet’s atmosphere more prominent and relatively easier to detect compared to a denser, drier world.
The groundbreaking discovery was detailed in the paper titled “A 1.55 R⊕ habitable-zone planet hosted by TOI-715, an M4 star near the ecliptic South Pole,” published in the prestigious journal “Monthly Notices of the Royal Astronomical Society.” Collaborative efforts from various telescopes, including Gemini-South, Las Cumbres Observatory telescopes, ExTrA telescopes, the SPECULOOS network, and the TRAPPIST-south telescope, were instrumental in confirming the authenticity of the finding.
This astronomical breakthrough not only expands our understanding of exoplanetary systems but also raises hopes of discovering potentially habitable worlds beyond our solar system. TOI-715 b stands as a testament to the advancements in astronomical technology and our relentless pursuit of unraveling the mysteries of the cosmos. As scientists eagerly await the capabilities of the James Webb Telescope, the quest for signs of extraterrestrial life takes an exhilarating leap forward.