El invasor errante

This 1972 Spanish-language science fiction pulp tells of the spaceship Scout U-104, commanded by Captain Daniel Snow, patrolling space to protect Earth. When Lieutenant Namura detects an unidentified meteor on radar approaching Earth at 24,000 miles per hour, Snow orders investigation. Spectral analysis by Lieutenant Marfa Krondaievna reveals the object is spherical, 37 feet in diameter, composed of crystallized carbon with unusually low density (2.178 rather than the expected 3+), suggesting it is hollow or filled with lightweight matter. As the ship approaches for closer observation, the mysterious object proves to be covered entirely in brilliant-cut diamonds of exceptional quality—each fifty carats minimum—arranged in perfect geometric patterns. This extraordinary discovery leads crew members, particularly Lieutenant Namura, to suspect intelligent construction rather than natural formation, raising questions about its origin and purpose as it descends toward Earth.