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Mission record

Cosmos 419

Also known as M-71S No.170, Cosmos419, Kosmos 419

U.S.S.R · Launched

Explore trajectory

Failed · Failure

A Soviet launch intended to be a Mars orbiting mission, presumably similar to the orbiter section of the later Mars 2 mission. NSSDCA records that it is widely believed this spacecraft was launched with the primary purpose of overtaking Mariner 8, which had been launched unsuccessfully two days earlier, and becoming the first Mars orbiter. The Proton booster successfully put the spacecraft into a low Earth parking orbit, but the Block D stage 4 failed to function due to a bad ignition timer setting, and the orbit decayed. Beginning in 1962, the name Cosmos was given to Soviet spacecraft which remained in Earth orbit, regardless of whether that was their intended final destination.

Destinations
Launch vehicle
Proton
Launch site
Tyuratam (Baikonur Cosmodrome), U.S.S.R
Countries
Soviet Union
Mission types
Orbiter

Chronology

Mission timeline

  1. Milestone

    Block D stage failed on a timer set for 1.5 years

    The SL-12/D-1-e Proton booster successfully put the spacecraft into low Earth parking orbit, but the Block D stage 4 failed to function due to a bad ignition timer setting (the timer, which was supposed to start ignition 1.5 hours after orbit was erroneously set for 1.5 years.) Typically Soviet planetary missions were initially put into an Earth parking orbit as a launch platform with a rocket engine and attached probe, and if the engine misfired or the burn was not completed the probes would be left in Earth orbit and given a Cosmos designation.

    Earth

  2. Launch

    Launched into a low Earth parking orbit

    NSSDCA's launch/orbital information page gives the launch date and time as 1971-05-10T16:58:42Z and an Earth orbit with a periapsis of 158.50 km, an apoapsis of 174.00 km, a period of 87.70 minutes and an inclination of 51.400°. The master catalog page describes the same orbit as low (174 km x 159 km) Earth parking orbit with an inclination of 51.4 degrees. One disagreement is recorded rather than resolved: that page says Mariner 8 had been launched two days earlier, while the same catalog dates Mariner 8's launch to 1971-05-09 and this one to 1971-05-10.

    Earth

  3. Mission end

    Re-entered two days after launch

    The orbit decayed and the spacecraft re-entered Earth's atmosphere 2 days later on 12 May 1971. NSSDCA's launch/orbital information page prints the same date as a Decay Date of 1971-05-12 and ends the Earth-orbit epoch at 1971-05-12 00:00:00.

    Earth

Mission architecture

Vehicles

  • Cosmos 419 · Orbiter

    Destinations: Mars

Trajectory record

Trajectory dataset not yet available

No verified trajectory dataset is committed for this mission, so Mission Atlas renders no path.

Provenance

Sources

Each source is listed once and labeled with the mission, event, trajectory, or destination/body context it supports.

Data verified through September 2, 2026