A team of astronomers has made an intriguing discovery while analyzing data from NASA's retired Kepler Space Telescope. They have identified a potential Earth-sized exoplanet, named HD 137010 b, situated approximately 146 light-years from our planet. This candidate appears to be orbiting a K-type dwarf star and is believed to have an orbital period close to one year, though it is expected to be significantly colder than Earth.
The evidence for this finding comes from a unique transit pattern observed in Kepler's K2 mission data from 2017. During this event, the star's brightness dimmed slightly for about ten hours, indicating that a planet may have passed in front of it. The transit depth was measured at around 225 parts per million, a subtle yet detectable signal that suggests the planet's radius is about 1.06 times that of Earth, with an estimated orbital period of 355 days.
Chilling Conditions
The cooler nature of the star HD 137010, which is less luminous than our Sun, means that the planet receives only about 29% of the sunlight that Earth does. This leads researchers to estimate that HD 137010 b could have an average temperature of around -90 degrees Fahrenheit (-68 degrees Celsius), earning it the nickname "ice-cold Earth." However, it's important to note that this temperature estimation does not confirm the presence or absence of an atmosphere, which could significantly affect surface conditions.
Despite its frigid classification, scientists remain interested in the planet's potential habitability. Even in the outer regions of a star's habitable zone, liquid water could exist if sufficient heat is retained by an atmosphere. The actual conditions on HD 137010 b remain uncertain, but its characteristics make it a compelling subject for further study.
To confirm the existence of HD 137010 b, astronomers will need to observe another transit event. This is challenging, as the timing of such events can be unpredictable, especially given the uncertainties surrounding the planet's orbital period. However, the star's brightness offers an advantage, allowing for clearer observations that could help secure the planet's classification.
In summary, HD 137010 b serves as a reminder that the data from missions like Kepler can still yield exciting discoveries long after their operational period has ended. As researchers continue to analyze existing data, the potential for new insights into our universe remains vast.