A wide range of educated opinions on the subject were offered by participants, including not only proponents such as James McDonald and J. Allen Hynek but also skeptics like astronomers William Hartmann and Donald Menzel.
Os participantes expuxeron un amplo abanico de opinións formadas no tema, incluíndo non só a partidarios como James McDonald e J. Allen Hynek senón tamén a escépticos como os astrónomos William Hartmann e Donald Menzel.