stars on black sky.

NASA sent a map to space to help aliens find Earth. Now it needs an update.

The map that NASA launched in 1972 could lead extraterrestrials to Earth. A new map, nearly 50 years later, provides even better directions.

A sparkling mass containing at least half a million stars—and some two dozen pulsars—the globular cluster known as 47 Tucanae is one of roughly 150 ancient stellar clumps orbiting the Milky Way galaxy.

Photograph by F. FERRARO, EUROPEAN SOUTHERN OBSERVATORY
This story appears in the October 2020 issue of National Geographic magazine.
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