He also responded to Amet’s rape allegations, his only public acknowledgment of the claims in the four years since Amet first blogged about them. He said they had been friends in graduate school at the University of Texas at Austin, and had been “intimate” on a few occasions. But he denied raping her. Noting her “odd” interests in New Age healing, he suggested she had a “false memory.” (Watson, Allers, and Amet have disputed much of Tyson’s statement. Tyson declined multiple requests to comment on this story.)

Now a fourth woman has told BuzzFeed News her experience of sexual harassment from Tyson. In January 2010, she recalled, she joined her then-boyfriend at a holiday party for employees of the American Museum of Natural History. Tyson, its most famous employee, drunkenly approached her, she said, making sexual jokes and propositioning her to join him alone in his office. In a 2014 email shared with BuzzFeed News, she described the incident to her own employer in order to shoot down a proposed collaboration with Tyson.

Over the course of nearly three years, BuzzFeed News has spoken with more than 30 people for this story, including the alleged victims and their families, Cosmos crew members, and graduate students and professors who were at UT Austin 30 years ago. Dozens more from that time did not reply to requests for interviews.