Fact-checked by Grok 2 weeks ago

Mars 2

Mars 2 was an uncrewed Soviet space probe launched on May 19, 1971, atop a Proton-K rocket, as part of the , consisting of an orbiter and an attached lander designed to study Mars' surface, atmosphere, gravity, and magnetic fields. The spacecraft arrived at Mars on November 27, 1971, with its lander becoming the first human-made object to reach the surface of the planet, though it crashed due to a premature release and a steep descent angle amid a global . Despite the lander's failure, the orbiter successfully entered a highly elliptical 18-hour around Mars and operated for nearly a year, completing 362 revolutions before being deactivated on August 22, 1972. The mission's primary objectives included deploying the 1,210 kg (2,670 lb) lander to conduct surface measurements such as , , and data using instruments to measure , , , and properties, while the 3,440 kg (7,580 lb) orbiter was equipped with cameras, radiometers, and spectrometers to image the surface and analyze atmospheric composition. Although the lander transmitted no data after impact in the Arcadia Planitia region at coordinates approximately 45°S, 48°E, the orbiter returned valuable scientific data, including about 60 photographs covering roughly 20% of Mars' surface, measurements of surface ranging from -100°F to 70°F (-73°C to 21°C), and insights into the planet's weak and gravitational anomalies. Mars 2's partial success marked a significant milestone in planetary exploration, paving the way for subsequent missions like its twin , and demonstrating the Soviet Union's early capabilities in interplanetary travel despite the challenges of Mars' thin atmosphere and harsh environment.

Mission Background

Objectives

The Mars 2 mission, launched as part of the Soviet Union's Project M-71 in , aimed to achieve the first Soviet entry into Mars and to deploy a lander for surface operations, marking a key step in the nation's planetary exploration efforts to surpass achievements in reaching another planet. Primary objectives included conducting to study the planet's upper atmosphere and compiling a radiothermal map of its surface from , while the lander was tasked with gathering on Mars' atmosphere and surface . The mission also sought to test rover mobility through the instrument attached to the lander, enabling analysis of parameters such as , rigidity, and temperature. Specific targets during the lander's descent focused on measuring , , , and , as well as analyzing atmospheric using onboard spectrometers, with data transmission planned at rates up to 1 bit per second over 30 to 900 seconds. The orbiter was designed to image the Martian surface for relief and surface features and over an eight-month operational period, while the lander aimed to capture panoramic images of the landing site at 72,000 bits per second if a succeeded, demonstrating entry, descent, and landing technologies at a 10-20° entry angle with parachute deployment at Mach 3.5. Additionally, the mission included imaging of Mars' moons to determine their shape, size, and . Within the broader Soviet , formed one half of a redundant 1971 campaign alongside , launched just days later to ensure at least one success in orbiting and landing on Mars amid prior mission failures in the . This paired approach underscored the program's emphasis on comprehensive environmental observations to support future explorations, despite challenges like dust storms that ultimately affected the lander's outcome.

Specifications

The Mars 2 , part of the Soviet M-71 mission, had a total launch mass of 4,650 kg, broken down into an orbiter of 3,440 kg and a lander of 1,210 kg. The orbiter featured a structural configuration measuring 4.1 m in height, 2.0 m in width, and 5.9 m in overall length when including deployed panels, designed to accommodate systems, scientific instruments, and communication equipment in a cylindrical bus with extended arrays. The lander was encapsulated in a spherical descent module with a 1.2 m , protected by a larger 2.9 m conical for . Power for the spacecraft was supplied by solar panels mounted on the orbiter, which could generate up to 1 kW of electrical power under optimal conditions near Earth, transitioning to reduced output in Mars orbit, with rechargeable batteries providing backup and peak load support; the lander depended entirely on non-rechargeable batteries for its short operational phase. The mission was planned for a primary operational duration of one year for the orbiter, allowing for extended orbital observations and data relay following the lander's deployment. Key instruments aboard Mars 2 included television cameras for imaging—with two units on the lander for panoramic surface views and two on the orbiter for high-resolution planetary and atmospheric photography—along with spectrometers for analyzing atmospheric and surface composition, magnetometers to measure local , barometers for pressure profiling during descent and on the surface, and accelerometers to monitor motion and entry dynamics. These instruments supported a high-level scientific focused on and in-situ measurements, enabling the spacecraft to contribute foundational data on Mars' environment despite operational challenges.

Launch and Journey

Launch Details

The Mars 2 spacecraft, part of the Soviet Union's , was launched on 19 May 1971 at 16:22 UTC from Launch Complex 81/24 at the in using a Proton-K carrier rocket augmented by a upper stage. This heavy-lift vehicle was selected for its capability to deliver the combined orbiter and lander payload of approximately 4,650 kg into a trans-Mars trajectory. The ascent followed a standard four-stage profile for the Proton family: the first stage provided initial thrust for liftoff and early ascent, followed by the second and third stages to reach a low Earth at around 200 km altitude and 51.4° inclination. The was jettisoned early in the flight to reduce mass, after which the upper stage ignited to execute the trans-Mars injection burn, placing the spacecraft on a 192-day heliocentric trajectory toward Mars. No anomalies were reported during the launch or immediate post-launch phases, confirming the success of the ascent and injection maneuvers. The orbiter and lander remained integrated throughout the early mission, with their separation occurring successfully later in flight prior to Mars arrival.

Interplanetary Cruise

The Mars 2 spacecraft embarked on its interplanetary cruise immediately following trans-Mars injection after launch on , 1971, enduring a journey of approximately 192 days until reaching Mars on November 27, 1971. Traveling along a heliocentric , the probe underwent three mid-course corrections to optimize its path toward the planet: the initial adjustment on June 5, 1971, followed by two additional maneuvers in late November, with the final one executed on using the onboard automatic and orbiter . These corrections ensured precise alignment for the subsequent orbital insertion and lander release, covering a total distance of roughly 220 million kilometers in the process. En route operations emphasized spacecraft maintenance, including periodic activations of key systems for health checks and communication verifications, primarily conducted during Earth-night periods to maintain telemetry links. The orbiter also served as a radar beacon and gathered preliminary data on interplanetary medium conditions, though no extensive scientific observations of Mars itself occurred during this phase.

Spacecraft Design

Orbiter

The Mars 2 orbiter was built around a cylindrical bus structure, measuring approximately 1.8 meters in diameter and 4.1 meters in height, which housed the main propellant tanks and core systems. This bus was equipped with deployable solar panels spanning 5.9 meters for power generation, multiple antennas including a 2.5-meter high-gain parabolic dish, and a dedicated instrument platform to mount scientific payloads. The design emphasized reliability for long-duration interplanetary operations, drawing from prior Soviet planetary probes. Propulsion for orbital maneuvers was provided by the KTDU-425 main engine, a hypergolic bipropellant capable of delivering up to 1,020 m/s of delta-v for Mars insertion and adjustments. Attitude control and fine pointing were managed by a set of cold gas using , ensuring precise orientation during passes and communication sessions. The orbiter's communication subsystem utilized an S-band transmitter operating at around 2 GHz for high-rate data transmission back to , relaying signals through ground stations equivalent to the Soviet Deep Space Network. The 2.5-meter high-gain antenna enabled directed transmission of scientific data and , supporting a data rate sufficient for relaying orbiter observations and any lander signals during the mission. Scientific instrumentation on the orbiter included two television cameras with focal lengths of 52 mm (wide-angle) and 350 mm (narrow-angle) for capturing images of the Martian surface and atmosphere at resolutions up to several kilometers per pixel. Additional payloads comprised an to measure surface and atmospheric temperatures, an spectrometer for analyzing upper atmospheric composition, and a to detect magnetic fields and interactions. These instruments operated primarily during periapsis passes to maximize data collection on Mars' , atmosphere, and environment.

Lander System

The Mars 2 lander system was integrated with the orbiter as part of the Soviet M-71 spacecraft design, developed by NPO Lavochkin, featuring a spherical landing capsule measuring 1.2 meters in attached to a descent stage for , deceleration, and surface operations. The configuration included a conical with a 2.9-meter to protect against entry heating, followed by a braking system and solid-fuel retrorockets to enable a on the Martian surface. The overall lander system had a total mass of 1,210 kg, with the descent apparatus weighing 358 kg. The descent sequence was engineered for automated execution upon separation from the orbiter: the provided initial aerodynamic braking during hypervelocity entry, with the jettisoned after deceleration; a system then deployed at altitudes ranging from approximately 2 to 32 km depending on entry angle, further slowing the capsule; and retrorockets fired near the surface to achieve a of about 6-12 m/s for . This hybrid approach combined aerodynamic, parachuted, and propulsive elements to handle Mars' thin atmosphere. Scientific instruments on the lander focused on in-situ analysis of the Martian environment and surface, including two television cameras for 360-degree panoramic imaging, sensors for measuring atmospheric pressure (barometer), temperature, and wind velocity (anemometer), a mass spectrometer for gas composition, X-ray and gamma-ray spectrometers mounted on deployable petals for soil elemental analysis, and a mechanical scoop for sampling surface materials and assessing physical properties. These instruments, totaling around 16 kg, were designed to operate briefly post-landing to provide direct measurements of local conditions. Power for the lander was supplied by rechargeable batteries, charged by the orbiter prior to separation, enabling 20 to 90 minutes of autonomous operation depending on activity levels. Communication relied on a UHF radio transmitter with four antennas, relaying directly to the orbiting parent at rates up to 72,000 bits per second for subsequent forwarding to . Integrated with the lander was the (Device for Soil Analysis on Mars) rover, a compact 4.5 kg unit measuring 215 × 160 × 60 mm, designed for short-range surface mobility using two rotating skis rather than wheels. Equipped with a dynamic for soil mechanical testing and a densitometer (X-ray-based) for measurements, the rover was tethered to the lander by a 15-meter for power and transfer, allowing it to extend the reach of stationary instruments while remaining connected. In ground tests, it demonstrated potential to traverse up to 200 meters, though operational constraints limited it to the tether length.

Arrival and Operations

Orbital Insertion

The Mars 2 spacecraft reached Mars on 27 November 1971 after a 191-day journey covering roughly 220 million kilometers. As the probe approached the planet, the attached lander was separated to initiate its independent descent, allowing the orbiter to prepare for capture maneuvers. The orbital insertion sequence culminated in a retrofire burn executed by the orbiter's KTDU-5 main engine, which decelerated the spacecraft sufficiently for Mars' to capture it into . This critical event successfully achieved an around Mars, with the orbiter entering a highly elliptical path inclined at 48.9 degrees. The accomplishment occurred despite a planet-encircling that had begun in September, partially obscuring initial views of the Martian surface and complicating early efforts. In the immediate aftermath, ground controllers used the orbiter's smaller thrusters for minor corrections to refine the orbital parameters and ensure stability, addressing any deviations from the targeted caused by the insertion burn or atmospheric influences. These adjustments enabled the to commence its primary observation phase, though the limited data collection until it subsided several months later.

Lander Descent

The Mars 2 lander separated from the orbiter on November 27, 1971, approximately 4 hours and 35 minutes before reaching periapsis. The descent module then entered the Martian atmosphere at an entry velocity of approximately 6 km/s, initiating the atmospheric interface at 13:47 UTC. The lander was equipped with a system for deceleration, as described in its design, but the descent profile proved challenging due to the planet's thin atmosphere. The lander entered the atmosphere at too steep an angle, causing the to deploy prematurely and the retro-rockets to fail to fire correctly amid the ongoing global . This resulted in a hard . The impact occurred at 14:47 UTC at coordinates 45°S, 47°E in the quadrangle. No signals were received from the lander after impact. For the brief duration of about 15 minutes before loss of contact, the lander transmitted data revealing atmospheric ranging from 5.5 to 6 mbar and temperatures varying from -110 °C to 13 °C. Despite the failure, the Mars 2 lander marked the first human-made object to reach the surface of Mars.

Orbiter Mission Phase

Following successful orbital insertion on 27 November 1971, the Mars 2 orbiter commenced its primary operational phase, conducting a series of scientific observations and communication relays over an 8-month period. The completed 362 orbits of Mars, with each orbit lasting approximately 18 hours in an elliptical path ranging from a pericenter altitude of 1,380 km to an apocenter of 24,940 km. Key activities included periodic attitude adjustments to align the spacecraft's instruments and communication antennas with or targeted surface regions, as well as attempts to relay any potential data transmissions from the accompanying lander, which ultimately proved unsuccessful due to the lander's rapid failure. The orbiter also executed multiple imaging passes using its television cameras to capture photographs of the Martian surface and atmosphere, prioritizing regions near pericenter for optimal resolution during the roughly 30-minute active observation windows per orbit. A major challenge arose from the global that engulfed Mars starting in September 1971 and reaching its peak intensity by late , severely degrading visibility and obscuring surface details in subsequent imagery. This storm limited the orbiter's ability to acquire clear photographs, with approximately 30 images successfully transmitted before the storm's onset and another 30 afterward, though the later ones suffered from reduced contrast and hazy conditions. The mission concluded on 22 August 1972 after fuel reserves were depleted and solar panels had degraded from prolonged exposure and accumulation, resulting in uncontrolled attitude and permanent loss of signal.

Scientific Results

Data from Orbiter

The Mars 2 orbiter conducted extensive imaging of the Martian surface, returning images with resolutions reaching up to 1 km per pixel. These images provided early views of geological features such as craters and other surface elements, despite significant obscuration by a planet-encircling during the mission's early phase. Notably, the orbiter delivered some of the initial observations of Mars' south polar region, revealing aspects of its icy cap and surrounding terrain. Atmospheric investigations by the orbiter focused on the upper layers through experiments, yielding measurements of atmospheric density profiles and ionospheric electron densities. These observations confirmed the presence of a thin dominated by atomic oxygen and , with peak electron densities occurring at altitudes around 130-140 km. The data highlighted diurnal and seasonal variations in the , influenced by solar radiation and the planet's lack of a significant intrinsic . Surface mapping efforts produced temperature profiles across the planet, with the northern polar cap measured at below -110 °C and equatorial regions reaching up to approximately 20 °C during local afternoon, illustrating the extreme thermal contrasts driven by Mars' thin atmosphere. The orbiter also tracked the 1971 global , estimating cloud heights up to 7 km and demonstrating how dust lofting altered atmospheric opacity and surface visibility. Additionally, magnetometer readings detected no global , only localized crustal anomalies, underscoring Mars' ancient cessation. Over its operational lifetime, the orbiter contributed to approximately 60 images returned by the M-71 program ( and ), relaying about 20 Mbit of scientific data back to via the Deep Space Network, encompassing , , and records that formed a foundational for subsequent .

Lander Outcomes

The Mars 2 lander achieved a partial success by transmitting limited during its and descent phase on November 27, 1971, marking the first human-made object to reach the Martian surface at approximately 45°S, 313°W. This data included measurements of around 6 mbar, along with temperature profiles and wind speeds indicative of turbulent conditions, confirming the presence of a thin carbon dioxide-dominated atmosphere. Despite this initial data return, the lander ultimately failed due to a steep entry angle that prevented proper deployment and activation of the braking rockets, leading to a high-speed estimated at 20 m/s. As a result, no surface images were captured, the attached rover was not deployed, and all post-landing scientific instruments—intended for soil analysis, , and seismic measurements—were lost. ceased 110 seconds after parachute deployment, precluding any further communication. In 2013, NASA's captured images of a possible debris field near the predicted impact site in , potentially confirming aspects of the crash dynamics. The crash highlighted critical vulnerabilities in lander to Martian storms, which generated winds exceeding several hundred km/h and reduced visibility, as well as the challenges of precise descent dynamics in an atmosphere with low density. With the lander rendered inoperable upon impact, no long-term surface data was obtained, and no relay of signals via the accompanying orbiter was possible after the failure. These outcomes underscored the need for enhanced environmental resilience and trajectory accuracy in future missions.

Legacy

Historical Significance

Mars 2 holds a pivotal place in the history of as the second spacecraft to enter orbit around another planet, achieving orbital insertion on November 27, 1971, just weeks after NASA's accomplished the feat on November 14. This success demonstrated the Soviet Union's advanced interplanetary navigation capabilities during the height of the , building on earlier flyby missions and paving the way for more complex Mars operations. The mission's lander component achieved another landmark by becoming the first human-made object to reach the Martian surface on , 1971, although it crashed due to a descent malfunction, marking the inherent challenges of early planetary landings. As part of the Soviet Mars program's 1971 double effort—paired with the near-identical launched nine days after Mars 2 on May 28—the mission showcased the reliability of the heavy-lift Proton-K rocket for deep-space payloads, enabling the transport of orbiter-lander combinations over vast distances. In the broader global context, Mars 2's arrival shortly after escalated the U.S.-Soviet rivalry in solar system exploration, with both nations targeting Mars during the same amid a planet-wide that tested mission resilience. The orbiter's observations, relayed back to , provided initial insights into Mars' atmospheric dynamics and , contributing to the foundational knowledge that shaped subsequent international efforts to understand the Red Planet. Mars 2's accomplishments are commemorated in chronologies of planetary missions as a key Soviet contribution to Mars exploration, and its approximate impact site in the Hellas Planitia region has been targeted for imaging by later probes, including NASA's Mars Reconnaissance Orbiter, underscoring its lasting historical footprint.

Influence on Future Missions

The failure of the Mars 2 lander, which crashed after entering the atmosphere at too steep an angle amid high winds and a global dust storm, highlighted the vulnerabilities in early entry, descent, and landing systems, prompting refinements in parachute deployment mechanisms and retro-rocket timing for the subsequent Mars 3 mission, which achieved the first soft landing on Mars despite limited data return. These Soviet experiences underscored the harsh Martian environment, influencing NASA's Viking program to incorporate more robust EDL designs, including larger parachutes and three-engine retro-rocket clusters for controlled descent, enabling the successful landings of Viking 1 and 2 in 1976. Furthermore, observations of the 1971 dust storm's impact on visibility and operations led to improved dust mitigation strategies, such as enhanced camera shielding and mission timing to coincide with clearer atmospheric conditions for Viking. The Mars 2 orbiter's eight-month operation yielded critical atmospheric profiles, temperature measurements, and partial surface imaging despite the , contributing to the foundational dataset on Mars' patterns and topography that complemented observations and informed Viking's landing site certification process by emphasizing low-elevation, flat terrains less prone to winds. This collective orbital reconnaissance confirmed the essential role of dedicated orbiters in precursor missions to support lander deployments, a paradigm adopted for Viking and subsequent explorations. The orbiter's success, despite the lander mishap, bolstered Soviet engineers' confidence in interplanetary navigation and propulsion, facilitating the 1973 Mars 5–7 missions and cross-pollinating propulsion technologies with the parallel program, which achieved multiple Venus landings in the 1970s. Post-Cold War collaborations, including U.S.-Russian space agreements, enabled broader sharing of Soviet Mars data through joint archives, enhancing global efforts. In modern analyses, NASA's used its camera to image potential Mars 2 crash sites in starting in 2014, providing high-resolution views to study debris dispersal and surface alteration from high-velocity impacts, though definitive identification remains elusive. Original Mars 2 telemetry and imaging data are preserved in international planetary repositories, such as NASA's Planetary Data System and the National Space Science Data Center, supporting contemporary climate modeling and mission planning.

References

  1. [1]
    Every mission to Mars ever | The Planetary Society
    Mars 2 and Mars 3. The identical Soviet Mars 2 and Mars 3 spacecraft, launched in 1971, each released descent craft 4.5 hours prior to their arrivals at Mars.
  2. [2]
    NASA Mars Orbiter Images May Show 1971 Soviet Lander
    Apr 11, 2013 · In 1971, the former Soviet Union launched the Mars 2 and Mars 3 missions to Mars. Each consisted of an orbiter plus a lander. Both orbiter ...
  3. [3]
    Search for the Mars 2 Debris Field
    Oct 29, 2014 · The Soviet Mars 2 lander was the first man-made object to touch the surface of the Red Planet when it crashed landed on 27 November 1971. It ...
  4. [4]
    [PDF] The Mars Missions - DESCANSO
    USSR/Mars 2. 5/19/71 Mars orbiter/lander. Achieved orbit 11/27/71 ... The twin Viking spacecraft (Viking 1 and Viking 2) each consisted of an orbiter and ...
  5. [5]
    [PDF] The Difficult Road to Mars - NASA
    In May 1971, with Project M-71, two spacecraft, Mars 2 and Mars 3, each with a lander, were launched. The lander for Mars 2 crashed on the surface of Mars.
  6. [6]
    Mars 2, 3 (Mars M71 #1, #2, #3) - Gunter's Space Page
    Jun 2, 2025 · Mars 2 was successfully launched on 19 May 1971. It reached successfully a 18 hour Mars orbit of 1380 km × 24940 km, inclined 48.9°.
  7. [7]
    Mars M-71
    Mars 2 released the descent module (1971-045D) 4.5 hours before reaching Mars on 27 November 1971. The descent system malfunctioned and the lander crashed ...
  8. [8]
    The Mars Orbiter That Almost Was Not | Drew Ex Machina
    May 22, 2014 · Mars 2 made its first course correction on ground command 17 days after launch on June 5, 1971. Because of the lack of a sufficiently ...
  9. [9]
    https://ntrs.nasa.gov/citations/19990054835
  10. [10]
    Meet the Very First Rover to Land on Mars - IEEE Spectrum
    Aug 27, 2012 · The robot weighed 4.5 kilos and was just a little bit smaller than a breadbox at 215 x 160 x 60 mm. It was packing a dynamic penetrometer and a ...
  11. [11]
    Russia's unmanned missions to Mars - RussianSpaceWeb.com
    (Mars-2). UR-500. Mars orbit, landing. Orbited Mars, landing failed. 16. 1971 May 28. USSR. 11. M-71 No. 172 (Mars-3). UR-500. Mars orbit, landing. Orbited Mars ...
  12. [12]
    [PDF] Russian Planetary Lander Missions - Lunar and Planetary Institute
    The Mars 2 and 3 landers carried a small walking robot called PROP-M. The robot had a mass of 4.5 kg and was tethered to the lander by a cable for direct ...
  13. [13]
    The First Rover on Mars - The Soviets Did It in 1971
    Aug 1, 1990 · Mars 2 and 3 was launched May 19, 1971 and reached the Red Planet on November 27. Mars 3 followed a few days later, launching on May 28 and ...<|control11|><|separator|>
  14. [14]
    ESA - Robotic Exploration of Mars - Missions to Mars
    The 560 kg spacecraft circled Mars twice each day for a full year, photographing the surface and analysing the atmosphere with infrared and ultraviolet ...
  15. [15]
    The Great Martian Storm of '71 | Scientific American
    Oct 21, 2013 · An early image of Mars after Mariner 9's arrival in November 1971, it's all dust, and a few mountain tops (NASA). The grid of small dots are ...
  16. [16]
    50 years ago: Mars 3 taught us to turn failure to success on Mars
    Dec 2, 2021 · “Mars 2 over-corrected as it turns out, and put the spacecraft into too steep of an angle of descent into the atmosphere,” Shindell says, and ...
  17. [17]
    [PDF] 2. Martian Ionosphere and Its Effects on Propagation (Plasma and ...
    Kolosov, M.A., Preliminary results of radio occultation studies of Mars by means of the Orbiter. Mars 2, Dokl. Akad. Nauk SSSR, 206, 1071, 1972. Luhmann ...
  18. [18]
    Radio Occultation Observations of the Ionospheres of Mars and Venus
    Jan 1, 1992 · Sidorenko, and V. P. Sorokin, Results of two-frequency radio occultation of “Mars - 2” by ionosphere of Mars, trans. from Radiotekhnika i ...
  19. [19]
    Mars 2 Is the First Spacecraft to Impact Mars | Research Starters
    The Soviet planetary probe Mars 2 was the first human-made object to impact the surface of the planet Mars. The mission proceeded according to plan until ...
  20. [20]
    [PDF] THE HISTORY OF MARS EXPLORATION
    Outcome of USSR Mars Campaign in 1971. First orbiter launch fails: key ... Lander results: first successful landing on Mars, but no data returned!
  21. [21]
    Mariner 9 - NASA Science
    Initial orbital parameters were about 870 × 11,130 miles (1,398 × 17,916 kilometers) at a 64.3-degree inclination. Another firing on the fourth revolution ...
  22. [22]
    https://science.nasa.gov/mission/mariner-9/
  23. [23]
    First spacecraft to land on Mars | Guinness World Records
    Mars 2 went first, releasing its lander on 27 November 1971, but lost contact almost immediately. It is now thought that the lander's parachute failed, sending ...<|control11|><|separator|>
  24. [24]
    50 Years Ago: Mariner 9 Launches to Orbit Mars - NASA
    Jun 1, 2021 · Mariner 9 launched May 30, 1971, entered orbit around Mars on Nov 13, 1971, and was the first spacecraft to orbit another planet, mapping 85% ...Missing: details | Show results with:details
  25. [25]
    Robotic Exploration of Mars - The hazards of landing on Mars - ESA
    Later Soviet landing attempts in 1971 and 1973 also ended in failure (or only partial success): the Mars 2 lander crashed into the Martian surface, after it ...<|control11|><|separator|>
  26. [26]
    45 Years Ago: Viking 1 and 2 off to Mars - NASA
    Aug 20, 2020 · The primary mission objectives of the Vikings were to place two orbiters around Mars and two landers on its surface in 1976 to obtain high ...
  27. [27]
    50 Years Ago, a Forgotten Mission Landed on Mars
    Nov 30, 2021 · When Mars 2 joined Mariner 9 in orbit, it sent down its own lander ... But its orbiter continued to transmit atmospheric data for eight ...
  28. [28]
    You Can't Fail Unless You Try: The Soviet Venus & Mars Missions of ...
    Nov 1, 2017 · Venera 1, which was launched on February 12, 1961, was the only one of the original batch of Soviet missions to Mars and Venus to survive launch but it ...
  29. [29]
    U.S.-Soviet Cooperation in Outer Space, Part 2: From Shuttle-Mir to ...
    May 7, 2021 · Records from Russian and American archives highlight the successes of joint operations ranging from the Shuttle-Mir program to the International Space Station.
  30. [30]
    Search for the Mars 2 Debris Field (ESP_037371_1350) - HiRISE
    Oct 29, 2014 · HiRISE acquired this image to aid in the search for the missing lander. If the Mars 2 debris field is found it could serve as a future landing ...Missing: 2007 | Show results with:2007
  31. [31]
    Welcome to the Planetary Data System
    The Planetary Data System (PDS) is a long-term archive of digital data products returned from NASA's planetary missions.Data Search · Data Standards · Information for Data Users · Data Release Calendar