The astronaut who tipped Kutyna off was Sally Ride. He kept that secret until after she died. He talks about it in this oral history of the disaster from popular mechanics:
<a href="http:&#x2F;&#x2F;www.popularmechanics.com&#x2F;space&#x2F;a18616&#x2F;an-oral-history-of-the-space-shuttle-challenger-disaster&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.popularmechanics.com&#x2F;space&#x2F;a18616&#x2F;an-oral-history...</a><p>&quot;Kutyna: On STS-51C, which flew a year before, it was 53 degrees [at launch, then the coldest temperature recorded during a shuttle launch] and they completely burned through the first O-ring and charred the second one. One day [early in the investigation] Sally Ride and I were walking together. She was on my right side and was looking straight ahead. She opened up her notebook and with her left hand, still looking straight ahead, gave me a piece of paper. Didn&#x27;t say a single word. I look at the piece of paper. It&#x27;s a NASA document. It&#x27;s got two columns on it. The first column is temperature, the second column is resiliency of O-rings as a function of temperature. It shows that they get stiff when it gets cold. Sally and I were really good buddies. She figured she could trust me to give me that piece of paper and not implicate her or the people at NASA who gave it to her, because they could all get fired.&quot;