1. Implications of the Discovery of Proxima b

    Artist's impression of the planet orbiting Proxima Centauri. Credit: ESO/M. Kornmesser Image credit: Artist's impression of the planet orbiting Proxima Centauri. Credit: ESO/M. Kornmesser

    The discovery of the new Earth-sized planet candidate in the habitable zone of the star Proxima Centauri, a little more than four light-years away, was announced by ESO on August 24, 2016. The press release followed weeks of speculation and was itself followed by a great deal of excitement. The research paper on the finding has now been published in Nature.

    To date, Proxima b is the closest exoplanet to us within a Goldilocks zone, putting it in a prime location for future observations, though whether the planet is actually habitable or possesses any other Earth-like qualities is still uncertain. Even so, Proxima b presents an interesting and significant target for research.

    “The close proximity of an Earth-class planet apparently in the habitable zone around a star that is radically different from our Sun is a great gift to the newly budding field of comparative exoplanetology,” says Penny Boston, director of the NASA Astrobiology Institute. “Studying this planet in its planetary system will allow us to look for any signs that we can interpret as being the product of some sort of life process.”

    If Proxima b fails to show signs of habitability, what we learn about what makes it uninhabitable will also be important. “With or without any signs of life, having a counter example that has some similarities with Earth but undoubtedly many differences will help to inform us about our own planet and how it stacks up to a distant cousin,” says Boston. “These are exciting times for astrobiology and exoplanet detection and characterization.”

    The latest news on Proxima b can be found at the Pale Red Dot blog: https://palereddot.org/.

    More on Proxima b

    Proxima b Is Surely Not “Earth-like.” But It’s a Research Magnet and Just May Be Habitable. (Many Worlds Blog)
    Found: Our Nearest Exoplanet Neighbor (Many Worlds Blog)
    Implications of the Discovery of Proxima b
    Pale Red Dot Blog

    Research Papers:
    The Habitability of Proxima Centauri b: II: Environmental States and Observational Discriminants
    The Habitability of Proxima Centauri b I: Evolutionary Scenarios

    Proxima Centauri B: A World of Possibilities