The Mariner program was conducted by the American space agency NASA to explore other planets. Between 1962 and late 1973, NASA's Jet Propulsion Laboratory (JPL) designed and built 10 robotic interplanetary probes named Mariner to explore the inner Solar System – visiting the planets Venus, Mars and Mercury for the first time, and returning to Venus and Mars for additional close observations.
Kosmos 21 was a Soviet spacecraft. This mission has been tentatively identified by NASA as a technology test of the Venera series space probes. It may have been an attempted Venus impact, presumably similar to the later Kosmos 27 mission, or it may have been intended from the beginning to remain in geocentric orbit. In any case, the spacecraft never left Earth orbit after insertion by the Molniya launcher. The orbit decayed on 14 November 1963, three days after launch.
Kosmos 27, also known as Zond 3MV-1 No.3 was a space mission intended as a Venus impact probe. The spacecraft was launched by a Molniya 8K78 carrier rocket from Baikonur. The Blok L stage and probe reached Earth orbit successfully, but the attitude control system failed to operate.
Mars 4, also known as 3MS No.52S was a Soviet spacecraft intended to explore Mars. A 3MS spacecraft launched as part of the Mars programme, it was intended to enter orbit around Mars in 1974. However, computer problems prevented orbital insertion from occurring.
Mars 5, also known as 3MS No.53S was a Soviet spacecraft launched to explore Mars. A 3MS spacecraft launched as part of the Mars programme, it successfully entered orbit around Mars in 1974. However, it failed a few weeks later.
Zond 3 was a 1965 space probe which performed a flyby of the Moon's far side, taking 28 quality photographs. It was a member of the Soviet Zond program while also being part of the Mars 3MV project. It was unrelated to Zond spacecraft designed for crewed circumlunar missions. It is believed that Zond 3 was initially designed as a companion spacecraft to Zond 2 to be launched to Mars during the 1964 launch window. The opportunity to launch was missed, and the spacecraft was launched on a Mars-crossing trajectory as a spacecraft test, even though Mars was no longer attainable.
Venera 3 was a Venera program space probe that was built and launched by the Soviet Union to explore the surface of Venus. It was launched on 16 November 1965 at 04:19 UTC from Baikonur, Kazakhstan, USSR. The probe comprised an entry probe, designed to enter the Venus atmosphere and parachute to the surface, and a carrier/flyby spacecraft, which carried the entry probe to Venus and also served as a communications relay for the entry probe.
Venera 16 was a spacecraft sent to Venus by the Soviet Union. This uncrewed orbiter was to map the surface of Venus using high resolution imaging systems. The spacecraft was identical to Venera 15 and based on modifications to the earlier Venera space probes. The latest data from the spacecraft were received on June 13, 1985, when it responded to the signal sent from Earth for Vega 1.
Venera 15 was a spacecraft sent to Venus by the Soviet Union. This uncrewed orbiter was to map the surface of Venus using high resolution imaging systems. The spacecraft was identical to Venera 16 and based on modifications to the earlier Venera space probes.
Venera 7 was a Soviet spacecraft, part of the Venera series of probes to Venus. When it landed the Venusian surface on 15 December 1970, it became the first spacecraft to soft land on another planet and the first to transmit data from there back to Earth.
Venera 2, also known as 3MV-4 No.4 was a Soviet spacecraft intended to explore Venus. A 3MV-4 spacecraft launched as part of the Venera programme, it failed to return data after flying past Venus.
Venera 4, also designated 4V-1 No.310, was a probe in the Soviet Venera program for the exploration of Venus. The probe comprised a lander, designed to enter the Venusian atmosphere and parachute to the surface, and a carrier/flyby spacecraft, which carried the lander to Venus and served as a communications relay for it.
Observations of the planet Venus include those in antiquity, telescopic observations, and from visiting spacecraft. Spacecraft have performed various flybys, orbits, and landings on Venus, including balloon probes that floated in the atmosphere of Venus. Study of the planet is aided by its relatively close proximity to the Earth, compared to other planets, but the surface of Venus is obscured by an atmosphere opaque to visible light.
The New Frontiers program is a series of space exploration missions being conducted by NASA with the purpose of furthering the understanding of the Solar System. The program selects medium-class missions which can provide high science returns.
Venera-D is a proposed Russian space mission to Venus that would include an orbiter and a lander to be launched in 2031. The orbiter's prime objective is to perform observations with the use of a radar. The lander, based on the Venera design, would be capable of operating for a long duration on the planet's surface. The "D" in Venera-D stands for "dolgozhivuschaya," which means "long lasting" in Russian.
Kosmos 167, or 4V-1 No.311, was a 1967 Soviet spacecraft intended to explore Venus. A spacecraft launched as part of the Venera programme, Kosmos 167 was intended to land on Venus but never departed low Earth orbit due to a launch failure.
DAVINCI is a planned mission for an orbiter and atmospheric probe to the planet Venus. Together with the separate VERITAS mission, which will also study Venus, it was selected by NASA on June 2, 2021 to be part of their Discovery Program. Its acronym is inspired by Leonardo da Vinci in honor of his scientific innovations, aerial sketches and constructions.
Kosmos 359 was an unmanned Soviet probe launched on 22 August 1970. The probe's intended purpose was to explore Venus, but an error caused the final-stage rocket to malfunction. This left the craft trapped in an elliptical orbit around Earth for 410 days before orbital decay and atmospheric entry. Kosmos 359 was launched five days after Venera 7 and had an identical design; had the craft not suffered a mission-ending failure, it would have landed on Venus shortly after Venera 7. To publicly acknowledge the failure of the attempted Venus lander would be a public relations disaster for the Soviet space program; after the mission failed, the Venera spacecraft was renamed Kosmos 359 in order to conceal the mishap from the public.
