When Aliens Attack: Would ET Eat Us, Enslave Us, or Exterminate Us for the Good of the Galaxy?

Just in time for the news that Jodi Foster helped save the main SETI array from funding doom, astronomers in Pennsylvania and Washington State have released an updated paper on the many scenarios we may face if aliens ever make contact.

Most media have so far jumped on one idea from the authors that extraterrestrial intelligence (ETI) might attack us not out of spite, “but instead out of a universalist desire to make the galaxy a better place.”

In other words, Earth may get blown up to make way for a hyperspace bypass, because aliens value galactic infrastructure more than our lives.

Or humans may be eradicated from the planet because we’re making a mess of our own ecosystem, and aliens are concerned about our destructive potential if we start to spread across the Milky Way.

Specifically, and perhaps not surprisingly, many headlines have targeted this line from the study:

Humanity may just now be entering the period in which its rapid civilizational expansion could be detected by an ETI because our expansion is changing the composition of Earth’s atmosphere (e.g. via greenhouse gas emissions), which therefore changes the spectral signature of Earth.

But this is just one sentence out of a 33-page paper that thoughtfully examines a full range of ET contact scenarios and how humans might respond.

The paper is a fun read and needs little de-jargonizing, so I will end by simply presenting this figure from the study that nicely summarizes the discussion (click the image to see a slightly larger version):

Changing Planet