Sunday, September 13, 2015

Early Evolution of Intelligence More Likely Toward Galactic Center, Model Shows

As argued previously by other parties. From the abstract:
Our model also shows that [the likelihood of the emergence of intelligence] is increasing with time. [According to our model and fitting actual observations,] intelligent life emerged at approximately the present time at Earth's galactocentric radius, but a similar level of evolutionary opportunity was available in the inner Galaxy more than 2 Gyr ago. Our findings suggest that the inner Galaxy should logically be a prime target region for searches for extraterrestrial intelligence and that any civilizations that may have emerged there are potentially much older than our own.
1. Note that their point is that we should be searching there, NOT announcing our presence in any particular direction, especially core-ward. We should not do that if we seriously think there may be aliens in that direction, and there is a nonzero chance of any of them not being warm and fuzzy.

2. Furthermore, as we look toward the galactic center, we should be looking for Super-Earths (more surface area means more reaction volume to produce complex chemistry for biogenesis.)

Morrison Ian S. and Gowanlock Michael G. Extending Galactic Habitable Zone Modeling to Include the Emergence of Intelligent Life. Astrobiology. August 2015, 15(8): 683-696. doi:10.1089/ast.2014.1192.