Mars 2 became the first spacecraft to reach Mars orbit successfully in November 1971.
The Soviet Mars 2 mission arrived during a period when several nations were sending probes toward Mars. Its orbiter entered orbit on 27 November 1971, but the mission’s lander crashed into the Martian surface during its descent and became the first human-made object to reach Mars.
Mars 3, launched at the same time, achieved the first soft landing on Mars, although its lander stopped transmitting shortly afterward. This distinction is important: Mars 2 was the first successful Mars orbiter, while Mars 3 was the first successful soft-landing attempt.
NASA’s Mariner 9 entered Mars orbit later in 1971 and became the first spacecraft to map the planet from orbit. That achievement is sometimes mistakenly attributed to Mars 2.