NASA Detects Repeating Signal from “Supertierra” Exoplanet 154 Light Years Away
A team of scientists has detected a repeating signal emanating from an exoplanet dubbed “Supertierra,” formally known as TOI-1846 b, located 154 light years from Earth. The discovery, made by the NASA TEES space telescope, has sparked intense interest due to the planet’s unusual characteristics and potential for harboring water.
Unveiling TOI-1846 b: A Planet in the “Radio Gap”
TOI-1846 b is nearly the same size as Earth, but possesses four times the mass – approximately 3.87 Earth masses. The planet completes an orbit around its host star, a small and cold red dwarf star designated as type M, in just under four days. What sets this exoplanet apart is the rare and repeated dimming of its star’s light, a signal first observed in March.
According to scientists, TOI-1846 b falls within the so-called “radio gap,” a classification for planets that are neither small, rocky worlds like Earth, nor large, gas-rich planets like Neptune. This categorization makes TOI-1846 b particularly intriguing, as its composition remains largely unknown.
A Surprisingly Warm, Potentially Habitable World?
Despite an estimated surface temperature of 600°F, researchers believe TOI-1846 b could potentially possess water. This possibility stems from the planet’s likely tidal lock, where one side perpetually faces its star, while the other remains in darkness. This extreme temperature contrast could allow water to become trapped in colder regions, preserved by the atmospheric dynamics.
“The temperature contrast could let the water be trapped in colder regions, according to how heat moves through the atmosphere,” one analyst noted.
How Exoplanets Are Discovered: The Transit Method
NASA explains that planets are often discovered by observing the slight dimming of a star’s light as the planet passes between the star and an observer’s line of sight – a phenomenon known as a transit. The frequency and intensity of these transits reveal the planet’s orbit and size. Smaller planets cause a smaller decrease in brightness, while larger planets cause a more significant dip.
The host star of TOI-1846 b is approximately 40% of the size and mass of our Sun, shining at around 6000°F. Because red dwarf stars are smaller and dimmer, planets must orbit closer to receive sufficient heat, making them easier to detect during transits.
Is TOI-1846 b Part of a Larger System?
Researchers suspect TOI-1846 b may not be alone. Subtle variations in its orbit suggest the presence of another planet within the same system, potentially orbiting further out in a colder, more habitable zone. Further investigation is needed to confirm this hypothesis and characterize any additional planets.
The discovery of TOI-1846 b represents a significant step forward in the search for potentially habitable worlds beyond our solar system, offering a tantalizing glimpse into the diversity of planets that may exist throughout the galaxy.
