A giant aircraft carrier built from ice

A Look Back at the 1960s PLATO Computing System

In the 1960s, researchers at the University of Illinois Urbana—Champaign developed a computer system that they hoped would expand access to education. They envisioned instructors usingthe system to build lessons, and students stationing themselves at machines—whose touchscreen plasma displays had a distinct orange glow—to complete coursework.

The shape of life

Last spring, the geobiologist Dominic Papineau and colleagues reported that fossilised microorganisms were identified in 3.77-4.28-billion-year-old iron-rich rock in Quebec: hematite tubes and filaments whose appearance is similar to microorganisms that today live in hydrothermal vents. Others dismissed their findings as ‘dubiofossils’, a term the geologist Hans Hofmann coined in 1972 to describe controversial fossils. ‘Fossils,’ Hofmann wrote, were proven biological; ‘pseudofossils’ resembled life but were inorganic; ‘dubiofossils’ (also known as Problematica or Miscellanea) were equivocal.

These early humans survived a supervolcano eruption 74,000 years ago