[LINK] "Possibilities of life around Alpha Centauri B"

[rfmcdonald]

The Dragon's Tales linked to an interesting paper, by Antolin Gonzalez, Rolando Cardenas, and John Hearnshaw. Gonzalez et al. suggest that Alpha Centauri B--an orange dwarf somewhat less massive and substantially dimmer than our own sun, already believed to host one exoplanet, the controversial Alpha Centauri Bb--could easily support planets hospitable to our sort of life.

We make a preliminary assessment on the habitability of potential rocky exoplanets around Alpha Centauri B. We use several indexes: the Earth Similarity Index, a mathematical model for photosynthesis, and a biological productivity model. Considering the atmospheres of the exoplanets similar to current Earth's atmosphere, we find consistent predictions of both the Earth Similarity Index and the biological productivity model. The mathematical model for photosynthesis clearly failed because does not consider the temperature explicitly. For the case of Alpha Centauri B, several simulation runs give 11 planets in the habitable zone. Applying to them above mentioned indexes, we select the five exoplanets more prone for photosynthetic life; showing that two of them in principle have better conditions than Earth for this kind of life.