Kepler-62 f is the outer companion to Kepler-62 e and is one of the most famous planets in Lisa Kaltenegger’s research. In 2013, she led the team that modeled this world, identifying it as a primary candidate for a terrestrial, potentially “Earth-like” planet. It is located approximately 1,200 light-years away in the constellation Lyra.
Key Physical Characteristics
- Planet Type: Terrestrial (rocky) world.
- Size: It is slightly smaller than its inner sibling, with a radius about 1.4 times that of Earth.
- Orbit: It completes one orbit around its star every 267 Earth days.
- The Star: It orbits an orange dwarf, which is smaller and cooler than our Sun but provides a very stable and long-lived environment for its planets.
Habitability & Environment
In Kaltenegger’s models, Kepler-62 f is the “cooler” counterpart to the tropical Kepler-62 e:
- Location: It sits on the outer edge of the habitable zone.
- Energy Intake: It receives only about 41% of the starlight that Earth gets from the Sun. This puts its energy levels somewhere between those of Earth and Mars.
- The Greenhouse Requirement: Kaltenegger’s research showed that for this planet to have liquid water, it would need a thick atmosphere with a strong greenhouse effect. Without such an atmosphere, it would likely be a frozen, icy world.
- Potential Water World: Like its sibling, it is theorized to be a “Water World,” potentially covered by a global ocean that might be partially or completely frozen depending on the heat trapped by its air.
Scientific Significance
- A Landmark Discovery: When it was found, it was one of the most Earth-like planets in terms of size and the energy it receives from its sun.
- Stability: Because it orbits an orange dwarf and is further out, it is exceptionally safe from the stellar flares that strip atmospheres away from red dwarf planets. This makes it a very stable place for life to potentially exist for billions of years.
- Comparative Science: By studying 62 e (warm) and 62 f (cool) in the same system, Kaltenegger was able to define the “inner” and “outer” boundaries of habitability for orange dwarf stars.
