Interplanetary Hide and Seek

Kepler-1649c was detected within previously analyzed data from the retired Kepler spacecraft. The automated algorithm Robovetter initially overlooked this planet, mislabeling it as a “false positive” due to temporary dimming in the star's brightness.

Such dimming can occur because of a planet's transit or fluctuations in the star's brightness. The Kepler False Positive Working Group later revisited the data for the Kepler 1649 system, revealing that this exoplanet completes an orbit around its star every 19 days and 12 hours.

While other exoplanets, such as TRAPPIST-1f and possibly Teegarden c, are known to be Earth-sized, Kepler-1649c stands out for being the closest match in size and temperature while also residing in its solar system's habitable zone.

This artistic representation shows Kepler-1649c orbiting its red dwarf star, with Kepler-1649b visible to the right. Image credit: NASA/Ames Research Center/Daniel Rutter.

Kepler-1649c is not alone; it shares its system with Kepler-1649b, which is 8% larger and 28% more massive than Earth. Discovered in 2017, this planet orbits its star at a distance significantly smaller than that between the Earth and the Sun.

“This particular discovery is thrilling—not only because it exists in the habitable zone and is Earth-sized, but also due to its interaction with the neighboring planet,” stated Andrew Vanderburg, a researcher at the University of Texas at Austin.

Signs of a Hidden Planet?

Interestingly, the orbital periods of both planets are related. For every four orbits completed by the newly found outer planet, Kepler-1649b completes nine—forming a 9:4 resonance.

This type of orbital resonance is also observable in our solar system, notably among some of Jupiter's and Saturn's moons. Typically, these resonances consist of simpler ratios, like 2:1 or 3:2, which raises the possibility of an undiscovered planet situated between Kepler-1649b and c.

Kepler-1649c is slightly larger than Earth. Image credit: NASA/Ames Research Center/Daniel Rutter.

Mae Jemison expressed, “Given the billions of stars in the universe and the planets orbiting them, it seems likely that life exists somewhere else.”

Red dwarf stars are prevalent throughout the galaxy. Although these stars emit little light or heat, they can unleash powerful flares that threaten any nearby life.

On Earth, intense solar eruptions pose risks to our technological civilization. For planets situated so close to their star, life could be obliterated instantly whenever it begins to evolve.

“This finding underscores the importance of human analysis of planet candidates, even as automation becomes more advanced, and suggests that Earth-like planets around M-dwarfs may be more frequent than those around larger stars,” researchers noted in a publication in The Astrophysical Journal Letters.

Kepler 1649c - an Earth like exoplanet? - YouTube

This video explores the characteristics of Kepler-1649c, discussing its Earth-like attributes and potential for hosting life.

Kepler 1649c - Earth Sized Exoplanet | Goldilocks Zone Planet Songs - YouTube

This video delves into the specifics of Kepler-1649c, emphasizing its position in the habitable zone and what that means for the possibility of life.