Venera 7 was the first spacecraft to land on Venus and transmit data from its surface. The Soviet probe reached the surface on December 15, 1970, and sent signals for about 23 minutes.
Venus presents an extreme landing environment, with crushing atmospheric pressure and temperatures hot enough to melt lead. Venera 7 was designed with a heavily strengthened landing capsule to survive the descent and touchdown.
The probe’s parachute system malfunctioned, so it landed at high speed and came to rest on its side. Despite this, its transmitter continued operating long enough to provide the first direct measurements from Venus’s surface.
Venera 9 later returned the first photographs from the Venusian surface, in 1975. That makes Venera 7 the first successful surface-data mission, not the first image mission.