Daily Portrait Series by Chiron Duong. Phenomenal.
Distance — immeasurable, humbling, stupefying distance — is the leitmotif of Agnes Giberne’s 1879 Sun, Moon, and Stars: A Book for Beginners. This text is less a Victorian astronomy primer than the foundation for a phenomenological star wisdom.
In his second paper, Caballero addresses this issue by conducting a statistical analysis of possible hostile civilizations in our galaxy and the possibility that one or more of these would detect signals coming from Earth (and possibly choose to invade). Because radio antennas and radar constantly leak signals into space, Cabellero felt a risk evaluation was necessary.