Vostok 6 expands who can enter space

Mariner 2 measured properties of the planet while passing it without entering orbit.

Mariner 2 showed that interplanetary spacecraft could return measurements from distant worlds.

The flyby provided direct data to compare with Earth-based astronomical observations.

Valentina Tereshkova became the first woman to travel in space.

The Vostok 6 mission began from Soviet Central Asia and went on to orbit Earth 48 times.

The spacecraft put Tereshkova in Earth orbit for a mission lasting nearly three days.

The satellites recorded the first known cosmic gamma-ray burst; its extraterrestrial source was recognized later.

The gamma-ray signal was initially detected by instruments built to monitor nuclear explosions.

The detection later helped establish the study of transient cosmic gamma-ray sources.

The recorded burst had no precise sky position at detection; its meaning became clear only with later analysis.