Rising greenhouse emissions could tip off aliens that we are a rapidly expanding threat, warns a report
http://www.guardian.co.uk/science/2011/ ... ilisations
This is a report compiled at Penn State on behalf of NASA's planetary sciences division.It may not rank as the most compelling reason to curb greenhouse gases, but reducing our emissions might just save humanity from a pre-emptive alien attack, scientists claim.
Watching from afar, extraterrestrial beings might view changes in Earth's atmosphere as symptomatic of a civilisation growing out of control – and take drastic action to keep us from becoming a more serious threat, the researchers explain.
