Scientist’s Deep Dive for Alien Life Leaves His Peers Dubious Avi Loeb, a Harvard astrophysicist, says that material recovered from the seafloor could be from an extraterrestrial spacecraft. His peers are skeptical. Scientist’s Deep Dive for Alien Life Leaves His Peers Dubious Avi Loeb, a Harvard astrophysicist, says that material recovered from the seafloor could be from an extraterrestrial spacecraft. His peers are skeptical. Scientist’s Deep Dive for Alien Life Leaves His Peers Dubious Avi Loeb, a Harvard astrophysicist, says that material recovered from the seafloor could be from an extraterrestrial spacecraft. His peers are skeptical.