01This week’s lead essay
Why the night sky is a record of time
Looking farther into space also means looking deeper into the past. A simple idea opens an extraordinary way of reading the universe.
PLATE 01 LIGHT / DISTANCE / TIME
02 · UPDATED WEEKLY
Current explainers
New evidence, explained with the background it needs.
03 · THE LIVING ARCHIVE
Choose a path through knowledge
Five connected rooms, from the first stars to the ideas shaping life today.04Worth understanding