Sub-Neptune planet candidate observed orbiting the orange dwarf star TIC 402710280

Observations from the Transiting Exoplanet Survey Satellite have revealed a candidate sub-Neptune planet orbiting the nearby orange dwarf star TIC 402710280. The planet completes one orbit every 36.34 days and maintains an equilibrium temperature of approximately 498 Kelvin. Detailed analysis of light curves confirms the transit signal originates from the target star rather than background interference.

Star system: TIC 402710280 | Distance from the Sun: 218 light years

A potential sub-Neptune planet candidate has been identified orbiting the orange dwarf star TIC 402710280. This star, located about 218 light-years away, was monitored using the Transiting Exoplanet Survey Satellite. A sub-Neptune is a type of planet that is larger than Earth but smaller than Neptune, representing one of the most common types of worlds found in our galaxy. This specific candidate completes a full trip around its host star in approximately 36.34 days.

The planet was identified through the transit method, which occurs when a planet passes in front of its host star from the perspective of an observer. This movement causes a temporary, measurable dip in the light emitted by the star. Researchers examined four distinct transit events recorded between 2021 and 2026. By analyzing the depth and duration of these light dips, they calculated the physical characteristics of the planet, including a radius about 3.75 times that of Earth and an estimated surface equilibrium temperature of 498 Kelvin.

While the detection is robust, some minor variations in the timing of the transit events were noted. These timing shifts could be caused by technical equipment limitations or potentially by gravitational interactions with other, as-yet-undetected bodies in the system. Further observations are planned for early 2027 to continue refining the orbital details of this distant world and to better understand the nature of the detected signals.

Key findings
The planet candidate has a radius of 3.75 times that of Earth.
The orbital period is confirmed at 36.34 days.
The equilibrium temperature is measured at 498 Kelvin.
The host star is classified as an orange dwarf.
Statistical analysis places the probability of this being a false positive at a very low level.

Scientific study

A 36.34-day Sub-Neptune Candidate Transiting the Nearby K Dwarf TIC 402710280 (external link)