Resumen de Are aliens among us? (cover story)
The article explains that in an effort to prove the existence of life on other planets, scientists are looking to find evidence of life that began independently on Earth. Scientists believe that if they can find an example of the establishment of two separate instances of life on Earth, it will prove that life on other Earth-like planets is unavoidable. INSETS: KEY CONCEPTS;DOES LIFE REQUIRE WATER?;Where to Look for Aliens;A Candidate Alien?
