Astronomers find rare Earth-mass rocky planet suitable for the search for signs of life
A newly discovered exoplanet could be worth searching for signs of life. Analyses by a team led by astronomer Diana Kossakowski of the Max Planck Institute for Astronomy describe a planet that orbits its home star, the red ...
This zone includes distances around the star for which liquid water can exist on the surface of the planet. In addition, the planet named Wolf 1069 b has an Earth-like mass. Very likely, this planet is a rocky planet that may also have an atmosphere. This makes the planet one of the few promising targets to search for signs of life-friendly conditions and biosignatures.
When astronomers search for planets outside our solar system, they are particularly interested in Earth-like planets. Of the more than 5,000 exoplanets they have discovered so far, only about a dozen have an Earth-like mass and populate the habitable zone, the range in a planetary system where water can maintain its liquid form on the planet's surface. With Wolf 1069 b, the number of such exoplanets on which life could have evolved has increased by one candidate.
A planet with eternal day and night
Detecting such low-mass planets is still a major challenge. Diana Kossakowski and her team at the Max Planck Institute for Astronomy in Heidelberg have taken on this task. As part of the Carmenes project, an instrument was developed specifically for the search of potentially habitable worlds. The Carmenes team is using this apparatus at the Calar Alto Observatory in Spain.
"When we analyzed the data of the star Wolf 1069, we discovered a clear, low-amplitude signal of what appears to be a planet of roughly Earth mass," says Diana Kossakowski. "It orbits the star within 15.6 days at a distance equivalent to one-fifteenth of the separation between the Earth and the sun," The results of the study have now been published in the journal Astronomy & Astrophysics.
Artist’s conception of a rocky Earth-mass exoplanet like Wolf 1069 b orbiting a red dwarf star. If the planet had retained its atmosphere, chances are high that it would feature liquid water and habitable conditions over a wide area of its dayside. Credit: NASA/Ames Research Center/Daniel Rutter
Simulated surface temperature map of Wolf 1069 b, assuming an Earth-like atmosphere. The map is centered at point that always faces the star. The temperatures are given in Kelvin. 273.15 Kelvin corresponds to zero degree Celsius. Liquid water would be possible on the planet’s surface inside the red circle. Credit: Kossakowski et al (2023) / MPIA
Illustration that compares three exoplanet systems of red dwarf stars hosting Earth-mass planets. The green rings indicate the individual habitable zones. Credit: MPIA graphics department/J. Neidel