A NASA scientist has said that aliens may have already visited the Earth. Silvano P. Colombano also claims that these alien lifeforms may have gone unnoticed by humans due to their extremely small size.
Colombano says that the extra-terrestrial beings would have looked quite a bit different than the carbon-based organisms currently roaming our planet, according to The Daily Mail. He also states that any visitors; past, present, or future, could easily be missed because of their tiny size. These super-intelligent interstellar traveling aliens could possess technology that humans cannot even comprehend at this point.
“Considering further that technological development in our civilization started only about 10,000 years ago and has seen the rise of scientific methodologies only in the past 500 years, we can surmise that we might have a real problem in predicting technological evolution even for the next thousand years, let alone 6 Million times that amount!”