Harvard Astrophysicist's Deep Sea Expedition Fuels Heated Extraterrestrial Life Debate

Astrophysicist Avi Loeb led expedition to retrieve fragments of fireball that crashed into sea in 2014.
Loeb believes fragments are from interstellar spacecraft, sparking skepticism from other astronomers.
Fragments consist mostly of iron not commonly found in retrieval area, preliminary analysis shows.
More evidence needed to determine if fragments actually linked to extraterrestrial life.
Loeb plans to continue investigating and searching for additional relics related to fireball crash.