Last month, theoretical physicist Avi Loeb made headlines with the sensational claim that tiny spherules recovered from the bottom of the ocean were probably of alien origin. “It’s most likely a technological gadget with artificial intelligence,” he said to The New York Times, which published a story today about the Harvard professor’s contentious claims. Although the biggest scientific breakthroughs often start with a bold hypothesis, Loeb’s peers believe the decorated astrophysicist’s assertions can be called many things — but “good science” isn’t one of them.

Loeb’s proclamations stem from an object that US government sensors logged on January 8th, 2014: a fireball from space that blazed into the western Pacific Ocean off the northeastern coast of Papua New Guinea. Highlighting its logged speed and direction as an anomaly, Loeb and undergraduate assistant Amir Siraj targeted the otherwise inconsequential planetary entry as an object worthy of further investigation.