[Rockhounds] Number of contactable alien civilisations estimated at 36

[Paul]

Scientists say most likely number of contactable

alien civilisations is 36. New calculations come up

with estimate for worlds capable of communicating

with others. Nicola Davis, The Guardian, June 15, 2020

https://www.theguardian.com/science/2020/jun/15/scientists-say-most-likely-number-of-contactable-alien-civilisations-is-36

The paper is:

Tom Westby and Christopher J. Conselice, 2020,

The Astrobiological Copernican Weak and Strong

Limits for Intelligent Life. The Astrophysical Journal,

Volume 896, Number 1

https://iopscience.iop.org/article/10.3847/1538-4357/ab8225

Yours,

Paul H.