Yup. And interestingly enough, that detail wasn't in the original novel by Carl Sagan. It was added for the movie, based on (AFAIK) a 1993 paper by David Blair

Yup. And interestingly enough, that detail wasn't in the original novel by Carl Sagan. It was added for the movie, based on (AFAIK) a 1993 paper by David Blair and Marjan Zadnik: https://articles.adsabs.harvard.edu/pdf/1993A%26A...278..669B https://articles.adsabs.harvard.edu/pdf/1993A%26A...278..669...