Docent David Barber, left, talks to Dennis Heng, 12, and his father Chamroeun Heng about J. Rob …

Docent David Barber, left, talks to Dennis Heng, 12, and his father Chamroeun Heng about J. Robert Oppenheimer at the Atomic Museum in Las Vegas Friday, July 28, 2023. (K.M. Cannon/Las Vegas Review-Journal) @KMCannonPhoto