The space agency's James Webb Space Telescope discovered a molecule called dimethyl sulphide, or DMS, on the distant planet, which on Earth can only be produced by life, according to a report from the BBC.
"On Earth, DMS is only produced by life. The bulk of it in Earth's atmosphere is emitted from phytoplankton in marine environments," University of Cambridge Profesor Nikku Madhusudhan, who led the research, told the BBC. More @ https://www.foxnews.com/us/nasa-detects-molecule-another-planet-only-produced-by-life
In this case it would be an invasion 120 light years from now, if they are very industrious molecules. By then the sun will have burned out and Earth will be toasted and gone.
Imagine driving all that way to kick somebody's ass and when you get there the lights are out all over and their old house isn't even there anymore.