Mission Atlas
← Mission directory

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

    Escape-stage ignition failed after a timer error

    Blok D did not ignite for trans-Mars injection. NSSDCA attributes this to a1.5-year timer setting; the later NASA chronology gives 150 hours while citing years as an alternative, and designer Perminov describes a reversed command. The intended ignition was about 1.5 hours after orbit; the source disagreement does not establish an actual burn epoch.

    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

Known dates and encounters do not uniquely determine a flight path. This mission’s sourced timeline is available above; no verified trajectory is currently published here.

What is needed to reconstruct this path?
  • A frame-qualified position and vector velocity at an epoch, or equivalent complete orbital elements.
  • Finer event-time constraints where required by an orbital reconstruction; the stored day/month/year precision is retained.
  • The actual failed-flight state history. Intended destinations are not evidence that the spacecraft reached them.

Provenance

Sources

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

Data verified through September 14, 2026