Observations and explorations of Venus

From Wikipedia, the free encyclopedia

Venus in real colors, processed from clear and blue filtered Mariner 10 images.
A photograph of the night sky taken from the seashore. Many glimmers of sunlight is on the horizon. There are many stars visible. Venus is at the center, much brighter than any of the stars, and its light can be seen reflected in the ocean.
Venus is always brighter than the brightest stars outside the Solar System, as can be seen here over the Pacific Ocean
Phases of Venus and evolution of its apparent diameter

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.

Historical observations and impact[edit]

Venus, from a 1550 edition of Guido Bonatti's Liber astronomiae.

As one of the brightest objects in the sky, Venus has been known since prehistoric times, and as such, many ancient cultures recorded observations of the planet. A cylinder seal from the Jemdet Nasr period indicates that the ancient Sumerians already knew that the morning and evening stars were the same celestial object. The Sumerians named the planet after the goddess Inanna, who was known as Ishtar by the later Akkadians and Babylonians.[1] She had a dual role as a goddess of both love and war, thereby representing a deity that presided over birth and death.[2][3] One of the oldest surviving astronomical documents, from the Babylonian library of Ashurbanipal around 1600 BC, is a 21-year record of the appearances of Venus.

The Pre-Columbian Mayan Dresden Codex, which calculates appearances of Venus.

Because the movements of Venus appear to be discontinuous (it disappears due to its proximity to the sun, for many days at a time, and then reappears on the other horizon), some cultures did not immediately recognize Venus as single entity; instead, they assumed it to be two separate stars on each horizon: the morning star and the evening star. The Ancient Egyptians, for example, believed Venus to be two separate bodies and knew the morning star as Tioumoutiri and the evening star as Ouaiti.[4] The Ancient Greeks called the morning star Φωσφόρος, Phosphoros (Latinized Phosphorus), the "Bringer of Light" or Ἐωσφόρος, Eosphoros (Latinized Eosphorus), the "Bringer of Dawn". The evening star they called Hesperos (Latinized Hesperus) (Ἓσπερος, the "star of the evening").[5] By Hellenistic times, the ancient Greeks identified it as a single planet,[6][7] which they named after their goddess of love, Aphrodite (Αφροδίτη), Phoenician Astarte,[8] a planetary name that is retained in modern Greek.[9] Hesperos was translated into Latin as Vesper and Phosphoros as Lucifer ("Light Bearer").

Venus was considered the most important celestial body observed by the Maya, who called it Chac ek,[10] or Noh Ek', "the Great Star" and Xux Ek', the Wasp Star.[11] The Maya based their religious calendar partially upon the movements of Venus and monitored its movements closely, including in the daytime. The positions of Venus and other planets were thought to influence life on Earth, so the Maya and other ancient Mesoamerican cultures timed wars and other important events based on their observations. In the Dresden Codex, the Maya included an almanac showing Venus's full cycle, in five sets of 584 days each (approximately eight years), after which the patterns repeated (since Venus has a synodic period of 583.92 days).[12] The Maya were aware of this synodic period, and could compute it to within a hundredth part of a day.[11]


In 1610 Galileo Galilei observed with his telescope that Venus showed phases, despite remaining near the Sun in Earth's sky (first image). This proved that it orbits the Sun and not Earth, as predicted by Copernicus's heliocentric model, and disproved Ptolemy's geocentric model (second image).

Because its orbit takes it between the Earth and the Sun, Venus as seen from Earth exhibits visible phases in much the same manner as the Earth's Moon. Galileo Galilei observed the phases of Venus in December 1610, an observation which supported Copernicus's then-contentious heliocentric description of the Solar System. He also noted changes in the size of Venus's visible diameter when it was in different phases, suggesting that it was farther from Earth when it was full and nearer when it was a crescent. This observation strongly supported the heliocentric model. Venus (and also Mercury) is not visible from Earth when it is full, since at that time it is at superior conjunction, rising and setting concomitantly with the Sun and hence lost in the Sun's glare.

Venus is brightest when approximately 25% of its disk is illuminated; this typically occurs 37 days both before (in the evening sky) and after (in the morning sky) its inferior conjunction. Its greatest elongations occur approximately 70 days before and after inferior conjunction, at which time it is half full; between these two intervals Venus is actually visible in broad daylight, if the observer knows specifically where to look for it. The planet's period of retrograde motion is 20 days on either side of the inferior conjunction. In fact, through a telescope Venus at greatest elongation appears less than half full due to Schröter's effect first noticed in 1793 and shown in 1996 as due to its thick atmosphere.

Venus in daylight at 5 p.m. in the southern hemisphere – December 2005

On rare occasions, Venus can actually be seen in both the morning (before sunrise) and evening (after sunset) on the same day. This scenario arises when Venus is at its maximum separation from the ecliptic and concomitantly at inferior conjunction; then one hemisphere (Northern or Southern) will be able to see it at both times. This opportunity presented itself most recently for Northern Hemisphere observers within a few days on either side of March 29, 2001, and for those in the Southern Hemisphere, on and around August 19, 1999. These respective events repeat themselves every eight years pursuant to the planet's synodic cycle.

Ground-based observations[edit]

Transits of Venus directly between the Earth and the Sun's visible disc are rare astronomical events. The first such transit to be predicted and observed was the Transit of Venus, 1639, seen and recorded by English astronomers Jeremiah Horrocks and William Crabtree. The observation by Mikhail Lomonosov of the transit of 1761 provided the first evidence that Venus had an atmosphere, and the 19th-century observations of parallax during Venus transits allowed the distance between the Earth and Sun to be accurately calculated for the first time. Transits can only occur either in early June or early December, these being the points at which Venus crosses the ecliptic (the orbital plane of the Earth), and occur in pairs at eight-year intervals, with each such pair more than a century apart. The most recent pair of transits of Venus occurred in 2004 and 2012, while the prior pair occurred in 1874 and 1882.

In the 19th century, many observers stated that Venus had a period of rotation of roughly 24 hours. Italian astronomer Giovanni Schiaparelli was the first to predict a significantly slower rotation, proposing that Venus was tidally locked with the Sun (as he had also proposed for Mercury). While not actually true for either body, this was still a reasonably accurate estimate. The near-resonance between its rotation and its closest approach to Earth helped to create this impression, as Venus always seemed to be facing the same direction when it was in the best location for observations to be made. The rotation rate of Venus was first measured during the 1961 conjunction, observed by radar from a 26 m antenna at Goldstone, California, the Jodrell Bank Radio Observatory in the UK, and the Soviet deep space facility in Yevpatoria, Crimea. Accuracy was refined at each subsequent conjunction, primarily from measurements made from Goldstone and Eupatoria. The fact that rotation was retrograde was not confirmed until 1964.

Before radio observations in the 1960s, many believed that Venus contained a lush, Earth-like environment. This was due to the planet's size and orbital radius, which suggested a fairly Earth-like situation as well as to the thick layer of clouds which prevented the surface from being seen. Among the speculations on Venus were that it had a jungle-like environment or that it had oceans of either petroleum or carbonated water. However, microwave observations by C. Mayer et al.,[13] indicated a high-temperature source (600 K). Strangely, millimetre-band observations made by A. D. Kuzmin indicated much lower temperatures.[14] Two competing theories explained the unusual radio spectrum, one suggesting the high temperatures originated in the ionosphere, and another suggesting a hot planetary surface.

In September 2020 a team at Cardiff University announced that observations of Venus using the James Clerk Maxwell Telescope and Atacama Large Millimeter Array in 2017 and 2019 indicated that the Venusian atmosphere contained phosphine (PH3) in concentrations 10,000 times higher than those that could be ascribed to any known non-biological source on Venus. The phosphine was detected at heights of at least 30 miles (48 kilometres) above the surface of Venus, and was detected primarily at mid-latitudes with none detected at the poles of Venus. This could have indicated the potential presence of biological organisms on Venus,[15][16] however, this measurement was later shown to be in error.[17][18]

Terrestrial radar mapping[edit]

After the Moon, Venus was the second object in the Solar System to be explored by radar from the Earth. The first studies were carried out in 1961 at NASA's Goldstone Observatory, part of the Deep Space Network. At successive inferior conjunctions, Venus was observed both by Goldstone and the National Astronomy and Ionosphere Center in Arecibo. The studies carried out were similar to the earlier measurement of transits of the meridian, which had revealed in 1963 that the rotation of Venus was retrograde (it rotates in the opposite direction to that in which it orbits the Sun). The radar observations also allowed astronomers to determine that the rotation period of Venus was 243.1 days, and that its axis of rotation was almost perpendicular to its orbital plane. It was also established that the radius of the planet was 6,052 kilometres (3,761 mi), some 70 kilometres (43 mi) less than the best previous figure obtained with terrestrial telescopes.

Interest in the geological characteristics of Venus was stimulated by the refinement of imaging techniques between 1970 and 1985. Early radar observations suggested merely that the surface of Venus was more compacted than the dusty surface of the Moon. The first radar images taken from the Earth showed very bright (radar-reflective) highlands christened Alpha Regio, Beta Regio, and Maxwell Montes; improvements in radar techniques later achieved an image resolution of 1–2 kilometres.

Observation by spacecraft[edit]

There have been numerous uncrewed missions to Venus. Ten Soviet Venera probes achieved a soft landing on the surface, with up to 110 minutes of communication from the surface, all without return. Launch windows occur every 19 months.

Early flybys[edit]

On February 12, 1961, the Soviet spacecraft Venera 1 was the first flyby probe launched to another planet. An overheated orientation sensor caused it to malfunction, losing contact with Earth before its closest approach to Venus of 100,000 km. However, the probe was first to combine all the necessary features of an interplanetary spacecraft: solar panels, parabolic telemetry antenna, 3-axis stabilization, course-correction engine, and the first launch from parking orbit.

Global view of Venus in ultraviolet light done by Mariner 10.

The first successful flyby Venus probe was the American Mariner 2 spacecraft, which flew past Venus in 1962, coming within 35,000 km. A modified Ranger Moon probe, it established that Venus has practically no intrinsic magnetic field and measured the temperature of the planet's atmosphere to be approximately 500 °C (773 K; 932 °F).[19]

The Soviet Union launched the Zond 1 probe to Venus in 1964, but it malfunctioned sometime after its May 16 telemetry session.

During another American flyby in 1967, Mariner 5 measured the strength of Venus's magnetic field. In 1974, Mariner 10 swung by Venus on its way to Mercury and took ultraviolet photographs of the clouds, revealing the extraordinarily high wind speeds in the Venusian atmosphere.

Early landings[edit]

Location of Soviet Venus landers

On March 1, 1966, the Venera 3 Soviet space probe crash-landed on Venus, becoming the first spacecraft to reach the surface of another planet. Its sister craft Venera 2 had failed due to overheating shortly before completing its flyby mission.

The descent capsule of Venera 4 entered the atmosphere of Venus on October 18, 1967, making it the first probe to return direct measurements from another planet's atmosphere. The capsule measured temperature, pressure, density and performed 11 automatic chemical experiments to analyze the atmosphere. It discovered that the atmosphere of Venus was 95% carbon dioxide (CO
), and in combination with radio occultation data from the Mariner 5 probe, showed that surface pressures were far greater than expected (75 to 100 atmospheres).

These results were verified and refined by the Venera 5 and Venera 6 in May 1969. But thus far, none of these missions had reached the surface while still transmitting. Venera 4's battery ran out while still slowly floating through the massive atmosphere, and Venera 5 and 6 were crushed by high pressure 18 km (60,000 ft) above the surface.

The first successful landing on Venus was by Venera 7 on December 15, 1970 — the first successful soft (non-crash) landing on another planet, as well as the first successful transmission of data from another planet’s surface to Earth.[20][21] Venera 7 remained in contact with Earth for 23 minutes, relaying surface temperatures of 455 to 475 °C (851 to 887 °F). Venera 8 landed on July 22, 1972. In addition to pressure and temperature profiles, a photometer showed that the clouds of Venus formed a layer ending over 35 kilometres (22 mi) above the surface. A gamma ray spectrometer analyzed the chemical composition of the crust.

Lander/orbiter pairs[edit]

Venera 9 and 10[edit]

First view and first clear 180-degree panorama of Venus's surface as well as any other planet than Earth (1975, Soviet Venera 9 lander). Black-and-white image of barren, black, slate-like rocks against a flat sky. The ground and the probe are the focus.[22]

The Soviet probe Venera 9 entered orbit on October 22, 1975, becoming the first artificial satellite of Venus. A battery of cameras and spectrometers returned information about the planet's clouds, ionosphere and magnetosphere, as well as performing bi-static radar measurements of the surface. The 660 kg (1,460 lb) descent vehicle[23] separated from Venera 9 and landed, taking the first pictures of the surface and analyzing the crust with a gamma ray spectrometer and a densitometer. During descent, pressure, temperature and photometric measurements were made, as well as backscattering and multi-angle scattering (nephelometer) measurements of cloud density. It was discovered that the clouds of Venus are formed in three distinct layers. On October 25, Venera 10 arrived and carried out a similar program of study.

Pioneer Venus[edit]

A map of Venus compiled from data recorded by NASA's Pioneer Venus Orbiter spacecraft beginning in 1978.

In 1978, NASA sent two Pioneer spacecraft to Venus. The Pioneer mission consisted of two components, launched separately: an orbiter and a multiprobe. The Pioneer Venus Multiprobe carried one large and three small atmospheric probes. The large probe was released on November 16, 1978, and the three small probes on November 20. All four probes entered the Venusian atmosphere on December 9, followed by the delivery vehicle. Although not expected to survive the descent through the atmosphere, one probe continued to operate for 45 minutes after reaching the surface. The Pioneer Venus Orbiter was inserted into an elliptical orbit around Venus on December 4, 1978. It carried 17 experiments and operated until the fuel used to maintain its orbit was exhausted and atmospheric entry destroyed the spacecraft in August 1992.

Further Soviet missions[edit]

Also in 1978, Venera 11 and Venera 12 flew past Venus, dropping descent vehicles on December 21 and December 25 respectively. The landers carried colour cameras and a soil drill and analyzer, which unfortunately malfunctioned. Each lander made measurements with a nephelometer, mass spectrometer, gas chromatograph, and a cloud-droplet chemical analyzer using X-ray fluorescence that unexpectedly discovered a large proportion of chlorine in the clouds, in addition to sulfur. Strong lightning activity was also detected.

In 1982, the Soviet Venera 13 sent the first colour image of Venus's surface and analysed the X-ray fluorescence of an excavated soil sample. The probe operated for a record 127 minutes on the planet's hostile surface. Also in 1982, the Venera 14 lander detected possible seismic activity in the planet's crust.

In December 1984, during the apparition of Halley's Comet, the Soviet Union launched the two Vega probes to Venus. Vega 1 and Vega 2 encountered Venus in June 1985, each deploying a lander and an instrumented helium balloon. The balloon-borne aerostat probes floated at about 53 km altitude for 46 and 60 hours respectively, traveling about 1/3 of the way around the planet and allowing scientists to study the dynamics of the most active part of Venus's atmosphere. These measured wind speed, temperature, pressure and cloud density. More turbulence and convection activity than expected was discovered, including occasional plunges of 1 to 3 km in downdrafts.

The landing vehicles carried experiments focusing on cloud aerosol composition and structure. Each carried an ultraviolet absorption spectrometer, aerosol particle-size analyzers, and devices for collecting aerosol material and analyzing it with a mass spectrometer, a gas chromatograph, and an X-ray fluorescence spectrometer. The upper two layers of the clouds were found to be sulfuric acid droplets, but the lower layer is probably composed of phosphoric acid solution. The crust of Venus was analyzed with the soil drill experiment and a gamma ray spectrometer. As the landers carried no cameras on board, no images were returned from the surface. They would be the last probes to land on Venus for decades. The Vega spacecraft continued to rendezvous with Halley's Comet nine months later, bringing an additional 14 instruments and cameras for that mission.

The multiaimed Soviet Vesta mission, developed in cooperation with European countries for realisation in 1991–1994 but canceled due to the Soviet Union disbanding, included the delivery of balloons and a small lander to Venus, according to the first plan.


Venera 15 and 16[edit]

In October 1983, Venera 15 and Venera 16 entered polar orbits around Venus. The images had a 1–2 kilometres (0.62–1.24 mi) resolution, comparable to those obtained by the best Earth radars. Venera 15 analyzed and mapped the upper atmosphere with an infrared Fourier spectrometer. From November 11, 1983, to July 10, 1984, both satellites mapped the northern third of the planet with synthetic aperture radar. These results provided the first detailed understanding of the surface geology of Venus, including the discovery of unusual massive shield volcanoes such as coronae and arachnoids. Venus had no evidence of plate tectonics, unless the northern third of the planet happened to be a single plate. The altimetry data obtained by the Venera missions had a resolution four times better than Pioneer's.


A portion of western Eistla Regio displayed in a three-dimensional perspective view acquired by the Magellan probe. The rise on the horizon is Gula Mons.

On August 10, 1990, the American Magellan probe, named after the explorer Ferdinand Magellan, arrived at its orbit around the planet and started a mission of detailed radar mapping at a frequency of 2.38 GHz.[24] Whereas previous probes had created low-resolution radar maps of continent-sized formations, Magellan mapped 98% of the surface with a resolution of approximately 100 m. The resulting maps were comparable to visible-light photographs of other planets, and are still the most detailed in existence. Magellan greatly improved scientific understanding of the geology of Venus: the probe found no signs of plate tectonics, but the scarcity of impact craters suggested the surface was relatively young, and there were lava channels thousands of kilometers long. After a four-year mission, Magellan, as planned, plunged into the atmosphere on October 11, 1994, and partly vaporized; some sections are thought to have hit the planet's surface.

Venus Express[edit]

Venus Express was a mission by the European Space Agency to study the atmosphere and surface characteristics of Venus from orbit. The design was based on ESA's Mars Express and Rosetta missions. The probe's main objective was the long-term observation of the Venusian atmosphere, which it is hoped will also contribute to an understanding of Earth's atmosphere and climate. It also made global maps of Venerean surface temperatures, and attempted to observe signs of life on Earth from a distance.

Venus Express successfully assumed a polar orbit on April 11, 2006. The mission was originally planned to last for two Venusian years (about 500 Earth days), but was extended to the end of 2014 until its propellant was exhausted. Some of the first results emerging from Venus Express include evidence of past oceans, the discovery of a huge double atmospheric vortex at the south pole, and the detection of hydroxyl in the atmosphere.


Akatsuki was launched on May 20, 2010, by JAXA, and was planned to enter Venusian orbit in December 2010. However, the orbital insertion maneuver failed and the spacecraft was left in heliocentric orbit. It was placed on an alternative elliptical Venerian orbit on 7 December 2015 by firing its attitude control thrusters for 1233-seconds.[25] The probe will image the surface in ultraviolet, infrared, microwaves, and radio, and look for evidence of lightning and volcanism on the planet. Astronomers working on the mission reported detecting a possible gravity wave that occurred on the planet Venus in December 2015.[26]


Venus in 2007 by MESSENGER

Several space probes en route to other destinations have used flybys of Venus to increase their speed via the gravitational slingshot method. These include the Galileo mission to Jupiter, and the Cassini–Huygens mission to Saturn, which made two flybys. During Cassini's examination of the radio frequency emissions of Venus with its radio and plasma wave science instrument during both the 1998 and 1999 flybys, it reported no high-frequency radio waves (0.125 to 16 MHz), which are commonly associated with lightning. This was in direct opposition to the findings of the Soviet Venera missions 20 years earlier. It was postulated that perhaps if Venus did have lightning, it might be some type of low-frequency electrical activity, because radio signals cannot penetrate the ionosphere at frequencies below about 1 megahertz. An examination of Venus's radio emissions by the Galileo spacecraft during its flyby in 1990 was interpreted at the time to be indicative of lightning. However, the Galileo probe was over 60 times further from Venus than Cassini was during its flyby, making its observations substantially less significant. In 2007, the Venus Express mission confirmed the presence of lightning on Venus, finding that it is more common on Venus than it is on Earth.[27][28]

MESSENGER passed by Venus twice on its way to Mercury. The first time, it flew by on October 24, 2006, passing 3000 km from Venus. As Earth was on the other side of the Sun, no data was recorded.[29] The second flyby was on July 6, 2007, where the spacecraft passed only 325 km from the cloudtops.[30]

BepiColombo flew by Venus on October 15th, 2020. During its second flyby of Venus, which occurred August 10th 2021, BepiColombo came 552 km near Venus' surface, and then afterwards left the planet's orbit and arrived at Mercury at a later date.[31][32][33][34] While BepiColombo approached Venus before making its second flyby of the planet, two monitoring cameras and seven science instruments were switched on.[35]

As of March 2023 Parker Solar Probe has transited Venus five times, on October 3, 2018, December 26, 2019, July 11, 2020, February 20, 2021, and October 16, 2021. Two more Venus transits will occur, on August 21, 2023, and November 6, 2024. Parker Solar Probe makes observations of the Sun and solar wind, and these Venus encounters enable Parker Solar Probe to perform gravity assists and travel closer to the Sun.[citation needed]

Future missions[edit]

Artist's impression of a Stirling cooled Venus Rover
An older concept for a Venus aircraft

The Venera-D spacecraft was proposed to Roscosmos in 2003 and the concept has been matured since then. It will be launched in 2029 and its prime purpose is to map Venus's surface using a powerful radar.[36] The mission would also include a lander capable to function for a long duration on the surface. As of late 2018, NASA is working with Russia on the mission concept, but the collaboration has not been formalized.[37]

India's ISRO is developing the Shukrayaan-1 orbiter concept, which as of 2022, is in the development phase. It is planned to be launched in December 2024, but its funding has not yet been requested.[38]

BepiColombo, launched in 2018 to study Mercury, made two flybys of Venus, on October 15, 2020, and August 10, 2021. Johannes Benkhoff, project scientist, believes BepiColombo's MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer) could possibly detect phosphine, but "we do not know if our instrument is sensitive enough".[39]

In June 2021, NASA announced two potential missions to Venus, VERITAS, an orbiter, and DAVINCI+, a combination orbiter/lander mission, both of the Discovery class.[40]

On October 6, 2021, the United Arab Emirates announced its intention to send a probe to Venus as soon as 2028. The probe would make observations of the planet while using it for a gravity assist to propel it to the Asteroid belt.[41]

In 2022, China's CNSA revealed the VOICE orbiter mission (Venus Volcano Imaging and Climate Explorer) launching in 2026 and arrive in Venus by 2027. VOICE's mission was expected to last 3-4 years and including the following payloads, a Microwave Radiometric Sounder (MRS), Polarimetric Synthetic Aperture Radar (PolSAR), and Ultraviolet-Visible-Near Infrared Multispectral Imager (UVN-MSI). The probe would return images of the surface with one-meter resolution and search the clouds for habitability and biosignatures.[42][43]

Timeline of Venus exploration[edit]

[44] Unofficial names used during development are listed in italics.

Past missions[edit]

Mission (1960–1969) Launch Arrival Termination Objective Result
Soviet space programme Tyazhely Sputnik 4 February 1961 4 February 1961 Flyby Launch failure
Soviet space programme Venera 1 12 February 1961 19 May 1961 26 February 1961 Flyby Partial failure (contact lost before the 19 May 1961 100,000 km flyby)
National Aeronautics and Space Administration, USA Mariner 1 22 July 1962 22 July 1962 Flyby Launch failure
Soviet space programme Venera 2MV-1 No.1 25 August 1962 28 August 1962 Lander Launch failure
National Aeronautics and Space Administration, USA Mariner 2 27 August 1962 14 December 1962 3 January 1963 Flyby Success (measurements suggested cool clouds and extremely hot surface)
Soviet space programme Venera 2MV-1 No.2 1 September 1962 6 September 1962 Lander Launch failure
Soviet space programme Venera 2MV-2 No.1 12 September 1962 14 September 1962 Flyby Launch failure
Soviet space programme Kosmos 21 11 November 1962 14 November 1962 Flyby? Launch failure (unknown mission: technology test or fly-by)
Soviet space programme Venera 3MV-1 No.2 19 February 1964 Flyby Launch failure
Soviet space programme Kosmos 27 27 March 1964 Landing Launch failure
Soviet space programme Zond 1 2 April 1964 14 July 1964 14 May 1964 Lander Failure (contact lost before a 100,000 km flyby)
Soviet space programme Venera 2 12 November 1965 27 February 1966 Lander Failure (contact lost before a 24,000 km flyby)
Soviet space programme Venera 3 16 November 1965 1 March 1966 Lander Failure (contact lost before the landing)
Soviet space programme Kosmos 96 23 November 1965 Flyby Failure (did not leave Earth orbit)
Soviet space programme Venera 4 12 June 1967 18 October 1967 18 October 1967 Lander Success (first chemical analysis of the Venusian atmosphere, measurements proved that Venus is extremely hot and its atmosphere far denser than expected)
National Aeronautics and Space Administration, USA Mariner 5 14 June 1967 19 October 1967 November 1967 Flyby Success (radio occultation atmospheric study, 3,990 km flyby)
Soviet space programme Kosmos 167 17 June 1967 Lander Failure (failed in Earth orbit)
Soviet space programme Venera 5 5 January 1969 16 May 1969 16 May 1969 Atmospheric probe Success (with knowledge about atmosphere gathered by Venera 4 its descent was optimised to analyze the atmosphere further deeper)
Soviet space programme Venera 6 10 January 1969 17 May 1969 17 May 1969 Atmospheric probe Success
Mission (1970–1979) Launch Arrival Termination Objective Result
Soviet space programme Venera 7 17 August 1970 15 December 1970 15 December 1970 Lander Success (first man-made spacecraft to successfully land on another planet and to transmit surface conditions to Earth, temperature 475±20 C and pressure 90±15 atm.)
Soviet space programme Kosmos 359 22 August 1970 Lander Failure
Soviet space programme Venera 8 27 March 1972 22 July 1972 22 July 1972 Lander Success
Soviet space programme Kosmos 482 31 March 1972 Lander Failure
National Aeronautics and Space Administration, USA Mariner 10 3 November 1973 5 February 1974 24 March 1975 Flyby Success (near-ultraviolet images of atmosphere shown unprecedented detail, 5,768 km flyby then continued towards Mercury)
Soviet space programme Venera 9 8 June 1975 20 October 1975 ~December 25, 1975? Orbiter Success (explored cloud layers and atmospheric parameters)
22 October 1975 22 October 1975 Lander Success (first images from the surface of another planet)
Soviet space programme Venera 10 14 June 1975 23 October 1975 Orbiter Success
25 October 1975 25 October 1975 Lander Success
National Aeronautics and Space Administration, USA Pioneer Venus 1 20 March 1978 4 December 1978 August 1992 Orbiter Success (over thirteen years studying the atmosphere and mapping the surface with S-band radar, conducted joint mapping with the 1990 Magellan probe)
National Aeronautics and Space Administration, USA Pioneer Venus 2 8 August 1978 9 December 1978 9 December 1978 Bus Success
Large probe Success
North probe Success
Night probe Success
Day probe Success (continued to send radio signals back after impact, for over an hour)
Soviet space programme Venera 11 9 September 1978 25 December 1978 February 1980 Flyby Success (as did Venera 12 found evidence of lightnings)
25 December 1978 25 December 1978 Lander Partial success (failed to deploy some instruments)
Soviet space programme Venera 12 14 September 1978 19 December 1978 April 1980 Flyby Success
21 December 1978 21 December 1978 Lander Partial success (failed to deploy some instruments)
Mission (1980–1989) Launch Arrival Termination Objective Result
Soviet space programme Venera 13 30 October 1981 1 March 1982 Flyby Success
1 March 1982 1 March 1982 Lander Success (first colour images from surface and X-ray fluorescence spectrometry soil characterisation)
Soviet space programme Venera 14 4 November 1981 Flyby Success
5 March 1982 5 March 1982 Lander Success
Soviet space programme Venera 15 2 June 1983 10 October 1983 ~July 1984 Orbiter Success (synthetic aperture radar on 15 and 16 probes allowed to map 25% of surface)
Soviet space programme Venera 16 7 June 1983 11 October 1983 ~July 1984 Orbiter Success
Soviet space programme Vega 1 15 December 1984 11 June 1985 30 January 1987 Flyby Success (intercepted the Halley comet next year)
11 June 1985 Lander Failed (surface experiments were inadvertently activated at 20 km from the surface)
13 June 1985 Balloon Success (first balloon in another planet, flew at least 11,600 km)
Soviet space programme Vega 2 20 December 1984 15 June 1985 24 March 1987 Flyby Success (intercepted the Halley comet next year)
15 June 1985 Lander Success
17 June 1985 Balloon Success (flew at least 11,100 km)
National Aeronautics and Space Administration, USA Magellan 4 May 1989 10 August 1990 12 October 1994 Orbiter Success (provided high-resolution gravimetric data for 94% of the planet, Synthetic Aperture Radar generated a high resolution map of 98% of the surface)
National Aeronautics and Space Administration, USA Galileo 18 October 1989 10 February 1990 21 September 2003 Flyby Success (took some data on its route to Jupiter, 16,106 km maximum approach)
Mission (1990–1999) Launch Arrival Termination Objective Result
National Aeronautics and Space Administration, USAEuropean Space Agency Cassini 15 October 1997 26 April 1998 and
24 June 1999
15 September 2017 2 Flybys Success (radio-frequency observations on its way to Saturn shown no signs of lightnings in Venus)
Mission (2000–2009) Launch Arrival Termination Objective Result
National Aeronautics and Space Administration, USA MESSENGER 3 August 2004 24 October 2006 and
5 June 2007
30 April 2015 2 Flybys Success (very close second flyby at 338 km in which visible, near-infrared, ultraviolet and X-ray spectrometry of the upper atmosphere was made simultaneously with the Venus Express probe, no observations in first flyby)
European Space Agency Venus Express 9 November 2005 11 April 2006 16 December 2014 Orbiter Success (detailed long-term observation of the Venusian atmosphere)
Mission (2010–2019) Launch Arrival Termination Objective Result
UNISEC Shin'en 20 May 2010 December 2010 21 May 2010 Flyby Failure (Last contact to 320,000 km of the Earth)
Japan Aerospace Exploration Agency IKAROS 20 May 2010 8 December 2010 23 April 2015 Flyby Success

Current missions[edit]

Mission (2010–present) Launch Arrival Termination Objective Result
Japan Aerospace Exploration Agency Akatsuki 20 May 2010 7 December 2015 ongoing Orbiter Orbital insertion maneuver failed in 2010; Akatsuki's second attempt at orbital insertion succeeded on 7 December 2015 using four attitude control thrusters.[45]
National Aeronautics and Space Administration, USA Parker Solar Probe 11 August 2018 3 October 2018
(1st flyby)
ongoing 7 Flybys Seven flybys from 2018 to 2024
European Space Agency Japan Aerospace Exploration Agency BepiColombo October 20, 2018 12 October 2020
(1st flyby)
ongoing 2 Flybys Two gravity-assist flybys of Venus in 2020 and 2021; several instruments will be activated to conduct Venus atmospheric and magnetospheric science
European Space Agency National Aeronautics and Space Administration, USA Solar Orbiter February 9, 2020 26 December 2020
(1st flyby)
ongoing 8 Flybys Eight gravity-assist flybys of Venus from 2020 to 2030;

Missions under study[edit]

Name Estimated launch Elements Notes
Indian Space Research Organisation Shukrayaan-1[46] December 2024[47][48] Orbiter Calls for payload proposals include a radar and atmosphere science
Balloons A balloon probe carrying 10 kilograms (22 pounds) payload to study the Venusian atmosphere at 55 kilometres (34 miles) altitude[49][50]
VOICE 2026 Orbiter To return images of the surface with one-meter resolution and search clouds for habitability and biosignatures[43]
National Aeronautics and Space Administration VERITAS 2028[51] Orbiter To map Venus' surface in high resolution using a synthetic aperture radar.[52]
National Aeronautics and Space Administration DAVINCI+ 2029–2030[51][53] Atmospheric probe and orbiter To measure the composition of Venus' atmosphere.[53]
Roscosmos Venera-D 2029[54] Orbiter To sense composition of the planet's atmosphere and its circulation patterns
Balloons Two balloons to sense acoustic and electrical activities of atmosphere
Microprobes Up to four atmospheric sensing probes launched from the balloons
Lander Designed for one-hour lifespan after touchdown in Tessera
European Space Agency EnVision 2032[55] Orbiter To map select regions of Venus' surface in high resolution using a synthetic aperture radar.


The Venus Multiprobe Mission proposed sending 16 atmospheric probes into Venus.[56]
NASA – Wind-powered Venus rover
(artist concept; 21 February 2020)[57]

To overcome the high pressure and temperature at the surface, a team led by Geoffrey Landis of NASA's Glenn Research Center produced a concept in 2007 of a solar-powered aircraft that would control a resistant surface rover on the ground. The aircraft would carry the mission's sensitive electronics in the relatively mild temperatures of Venus' upper atmosphere.[58] Another concept from 2007 suggests to equip a rover with a Stirling cooler powered by a nuclear power source to keep an electronics package at an operational temperature of about 200 °C (392 °F).[59]

In 2020 NASA's JPL launched an open competition, titled "Exploring Hell: Avoiding Obstacles on a Clockwork Rover", to design a sensor that could work on Venus's surface.[60]

Other examples of mission concepts and proposals include:

Mission name Institution Year
Type References
AREE NASA 2020 Wind-powered surface rover [57]
CUVE NASA 2017 Orbiter [61][62]
EnVision ESA 2017 Orbiter [63]
EVE ESA 2005 Lander, orbiter and balloon. [64]
HAVOC NASA 2015 Crewed zeppelin [65]
HOVER NASA 2019 Orbiter [66]
Shukrayaan-1 ISRO 2012 Orbiter and atmospheric balloon, in configuration study phase. [67][68]
VAMP NASA 2012 Inflatable semi-buoyant aircraft. [69][70]
Venera-D Roscosmos 2003 Orbiter, lander and balloons; in configuration study phase. [71]
VICI NASA 2017 Lander, 3.5 hrs on surface [72]
VISAGE NASA 2017 Lander [73]
VISE NASA 2003 Lander [74]
VMPM NASA 1994 Venus Multiprobe Mission, atmospheric probes [75]
VOX NASA 2017 Orbiter [76][77]
Zephyr NASA 2016 Sail-driven surface rover. [78]


Research on the atmosphere of Venus has produced significant insights not only about its own state but also about the atmospheres of other planetary objects, especially of Earth. It has helped to find and understand the depletion of Earth's ozone in the 1970s and 1980s.[79]

The voyage of James Cook and his crew of HMS Endeavour to observe the Venus transit of 1769 brought about the claiming of Australia at Possession Island for colonisation by Europeans.

See also[edit]


  • In Isaiah 14:12 in the Latin Vulgate translation of the Bible, Jerome translated the Greek term heosphoros in the Septuagint and the Hebrew term helel in the Hebrew Bible as lucifer, meaning "light bearer". Later English translators, influenced by the Vulgate's rendering of lucifer for helel, introduced Lucifer with a capital into the English translations of the Bible, thereby changing the Latin descriptive term to a personal name. This has caused "Lucifer" to become viewed as a code name for Satan, instead of being a descriptive term by which Isaiah compared the Babylonian king to the bright planet Venus.


  1. ^ Cooley, Jeffrey L. (2008). "Inana and Šukaletuda: A Sumerian Astral Myth". KASKAL. 5: 161–172. ISSN 1971-8608.
  2. ^ Meador, Betty De Shong (2000). Inanna, Lady of Largest Heart: Poems of the Sumerian High Priestess Enheduanna. University of Texas Press. p. 15. ISBN 978-0-292-75242-9.
  3. ^ Littleton, C. Scott (2005). Gods, Goddesses, and Mythology. Vol. 6. Marshall Cavendish. p. 760. ISBN 978-0761475651.
  4. ^ Cattermole, Peter John; Moore, Patrick (1997). Atlas of Venus. Cambridge University Press. p. 9. ISBN 978-0-521-49652-0.
  5. ^ "Definition of Hesperus". www.thefreedictionary.com. Retrieved 12 May 2013.
  6. ^ Fox, William Sherwood (1916). The Mythology of All Races: Greek and Roman. Marshall Jones Company. p. 247. ISBN 978-0-8154-0073-8. Retrieved 2009-05-16.
  7. ^ Greene, Ellen (1996). Reading Sappho: contemporary approaches. University of California Press. p. 54. ISBN 978-0-520-20601-4.
  8. ^ Greene, Ellen (1999). Reading Sappho: contemporary approaches. University of California Press. p. 54. ISBN 978-0-520-20601-4.
  9. ^ "Greek Names of the Planets". 25 April 2010. Retrieved 2012-07-14. Aphrodite is the Greek name of the planet Venus, which is named after Aphrodite, the goddess of Love. See also the Greek article about the planet.
  10. ^ The Book of Chumayel: The Counsel Book of the Yucatec Maya, 1539–1638. Richard Luxton. 1899. pp. 6, 194. ISBN 9780894122446.
  11. ^ a b Sharer, Robert J.; Traxler, Loa P. (2005). The Ancient Maya. Stanford University Press. ISBN 978-0-8047-4817-9.
  12. ^ Milbrath, Susan (1999). Star Gods of The Mayans : Astronomy in Art, Folklore, and Calendars. Austin, TX: University of Texas Press. pp. 200–204, 383. ISBN 978-0-292-79793-2.
  13. ^ Mayer, C. H.; McCollough, T. P.; Sloanaker, R. M. (1958). "Observations of Venus at 3.15-CM Wave Length". Astrophysical Journal. 127: 1–9. Bibcode:1958ApJ...127....1M. doi:10.1086/146433.
  14. ^ Kuz'min, A. D.; Marov, M. Y. (1 June 1975). "Fizika Planety Venera" [Physics of the Planet Venus]. "Nauka" Press. p. 46. Retrieved 19 September 2020. The lack of evidence that the Venusian atmosphere is transparent at 3 cm wavelength range, the difficulty of explaining such a high surface temperature, and a much lower brightness temperature measured by Kuz'min and Salmonovich [80, 81] and Gibson [310] at a shorter wavelength of 8 mm all provided a basis for a different interpretation of the radio astronomy measurement results offered by Jones [366].
  15. ^ Greaves, Jane S.; Richards, A.M.S.; Bains, W (14 September 2020). "Phosphine gas in the cloud decks of Venus". Nature Astronomy. 5 (7): 655–664. arXiv:2009.06593. Bibcode:2021NatAs...5..655G. doi:10.1038/s41550-020-1174-4. S2CID 221655755. Retrieved 16 September 2020.
  16. ^ Sample, Ian (14 September 2020). "Scientists find gas linked to life in atmosphere of Venus". The Guardian. Retrieved 16 September 2020.
  17. ^ "Is the Phosphine Biosignature on Venus a Calibration Error?". Sky & Telescope. 17 November 2020.
  18. ^ Snellen, I. a. G.; Guzman-Ramirez, L.; Hogerheijde, M. R.; Hygate, A. P. S.; Tak, F. F. S. van der (1 December 2020). "Re-analysis of the 267 GHz ALMA observations of Venus - No statistically significant detection of phosphine". Astronomy & Astrophysics. 644: L2. Bibcode:2020A&A...644L...2S. doi:10.1051/0004-6361/202039717. ISSN 0004-6361. S2CID 224803085.
  19. ^ "Mariner 2". 6 March 2015.
  20. ^ "Science: Onward from Venus". Time. 8 February 1971. Archived from the original on December 21, 2008. Retrieved 2 January 2013.
  21. ^ Siddiqi, Asif A. (2018). Beyond Earth: A Chronicle of Deep Space Exploration, 1958–2016 (PDF). The NASA history series (second ed.). Washington, DC: NASA History Program Office. pp. 1, 3. ISBN 9781626830424. LCCN 2017059404. SP2018-4041.
  22. ^ "Venera 9's landing site". The Planetary Society. Retrieved 16 September 2020.
  23. ^ Braeunig, Robert A. (2008). "Planetary Spacecraft". Archived from the original on 2017-03-20. Retrieved 2009-02-15.
  24. ^ W. T. K. Johnson, "Magellan Imaging Radar Mission To Venus," PROCEEDINGS OF THE IEEE, Vol 19, No 6, June 1991, available from IEEE
  25. ^ "Live from Sagamihara: Akatsuki Orbit Insertion - Second Try".
  26. ^ Chang, Kenneth (16 January 2017). "Venus Smiled, With a Mysterious Wave Across Its Atmosphere". New York Times. Retrieved 17 January 2017.
  27. ^ Hand, Eric (2007-11-27). "European mission reports from Venus". Nature (450): 633–660. doi:10.1038/news.2007.297. S2CID 129514118.
  28. ^ "Venus offers Earth climate clues". BBC News. November 28, 2007. Retrieved 2007-11-29.
  29. ^ "MESSENGER performs first flyby of Venus". NASA's Solar System Exploration: News & Events: News Archive. Archived from the original on 2008-10-05. Retrieved 2007-08-20.
  30. ^ "MESSENGER performs second flyby of Venus". NASA's Solar System Exploration: News & Events: News Archive. Archived from the original on 2008-10-05. Retrieved 2007-08-20.
  31. ^ "BepiColombo's second Venus flyby in images". European Space Agency. Retrieved 8 December 2021.
  32. ^ Pultarova, Tereza (August 11, 2021). "Mercury-bound spacecraft snaps selfie with Venus in close flyby (photo)". Space.com. Retrieved December 8, 2021.
  33. ^ "BepiColombo flies by Venus en route to Mercury". ESA. Retrieved 25 June 2021.
  34. ^ ""A flawless, radiant, #Mercuryflyby"". Twitter. Twitter. 1 October 2021. Retrieved 8 December 2021.
  35. ^ "BepColombo Venus Flybys". European Space Agency. Retrieved December 8, 2021.
  36. ^ Zak, Anatoly (5 March 2021). "New promise for the Venera-D project". RussianSpaceWeb. Retrieved 7 March 2021.
  37. ^ Development of the Venera-D Mission Concept, from Science Objectives to Mission architecture. 49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083).
  38. ^ "ISRO gears up for Venus mission, invites proposals from scientists". 25 April 2017.
  39. ^ O'Callaghan, Jonathan. "In A Complete Fluke, A European Spacecraft Is About To Fly Past Venus – And Could Look For Signs Of Life". Forbes. Retrieved 27 September 2020.
  40. ^ Chang, Kenneth. "New NASA Missions Will Study Venus, a World Overlooked for Decades". New York Times. Retrieved 2 June 2021.
  41. ^ Ryan, Jackson (October 6, 2021). "Daring mission to Venus and the asteroid belt announced by the UAE". cnet.com. Retrieved October 7, 2021.
  42. ^ Andrew Jones published (2022-07-14). "China's proposed Venus mission would investigate the planet's atmosphere and geology". Space.com. Retrieved 2023-03-10.
  43. ^ a b "VOICE: Will this Chinese candidate mission to Venus fly?". The Planetary Society. Retrieved 2023-03-10.
  44. ^ "Russia's unmanned missions to Venus".
  45. ^ Clark, Stephan. "Japanese probe fires rockets to steer into orbit at Venus". Retrieved 7 December 2015.
  46. ^ Srikanth, B.R. "After Mars, Isro aims for Venus probe in 2-3 years". Archived from the original on May 30, 2015. Retrieved May 30, 2015.
  47. ^ "FRANCE-INDIA SPACE COOPERATION - FOCUS ON CLIMATE SCIENCE AND SPACE EXPLORATION". presse.cnes.fr. 30 September 2020. Retrieved 2020-12-05.
  48. ^ Singh, Surendra (5 May 2022). "venus: Isro to join race to Venus, eyes 2024 orbiter launch". The Times of India. Retrieved 2022-05-13.
  49. ^ "India seeks collaborators for a mission to Venus, the neglected planet". 2018-11-21.
  50. ^ "India-France Joint Vision for Space Cooperation (New Delhi, 10 March 2018)".
  51. ^ a b Roulette, Joey (2 June 2021). "NASA will send two missions to Venus for the first time in over 30 years". The Verge. Retrieved 2 June 2021.
  52. ^ Hensley, S.; Smrekar, S. E (2012). "VERITAS: A Mission Concept for the High Resolution Topographic Mapping and Imaging of Venus". American Geophysical Union, Fall Meeting. 2012: P33C–1950. Bibcode:2012AGUFM.P33C1950H.
  53. ^ a b Steigerwald, William; Jones, Nancy Neal (2 June 2021). "NASA to Explore Divergent Fate of Earth's Mysterious Twin with Goddard's DAVINCI+". NASA. Retrieved 2 June 2021.
  54. ^ Zak, Anatoly (5 March 2021). "New promise for the Venera-D project". RussianSpaceWeb. Retrieved 2 June 2021.
  55. ^ "EnVision: Understanding why Earth's closest neighbour is so different" (PDF). ESA. Retrieved 10 June 2021.
  56. ^ Discovery Missions Under Consideration
  57. ^ a b Segal, Matthew; Skelly, Claire A. (21 February 2020). "NASA Wants Your Help Designing a Venus Rover Concept". NASA. Retrieved 22 February 2020.
  58. ^ "To conquer Venus, try a plane with a brain". NewScience. Retrieved 2007-09-03.
  59. ^ Landis, Geoffrey A.; Kenneth C. Mellott (December 2007). "Venus surface power and cooling systems". Acta Astronautica. 61 (11–12): 995–1001. Bibcode:2007AcAau..61..995L. doi:10.1016/j.actaastro.2006.12.031.
  60. ^ Holly Yan (2020). "Here's your chance to design equipment for NASA's proposed Venus rover and win $15,000". CNN. Retrieved 24 February 2020.
  61. ^ NASA studies CubeSat mission to solve Venusian mystery. Lori Keesey. Published by PhysOrg. August 15, 2017.
  62. ^ CUVE – CubeSat UV Experiment: Unveil Venus' UV Absorber with CubeSat UV Mapping Spectrometer. (PDF) V. Cottini, Shahid Aslam, Nicolas Gorius, Tilak Hewagama. Lunar and Planetary Science Conference, at The Woodlands, Texas, USA, Volume: LPI Contrib. No. 2083, 1261. March 2018.
  63. ^ EnVision: Understanding why our most Earth-like neighbor is so different. M5 proposal. Richard Ghail. arXiv.org
  64. ^ Chassefière, E.; Korablev, O.; Imamura, T.; Baines, K. H.; Wilson, C. F.; Titov, D. V.; Aplin, K. L.; Balint, T.; Blamont, J. E. (2009-03-01). "European Venus Explorer (EVE): an in-situ mission to Venus". Experimental Astronomy. 23 (3): 741–760. Bibcode:2009ExA....23..741C. doi:10.1007/s10686-008-9093-x. ISSN 0922-6435.
  65. ^ Arney, Dale; Jones, Chris (2015). HAVOC: High Altitude Venus Operational Concept – An Exploration Strategy for Venus. SPACE 2015: AIAA Space and Astronautics Forum and Exposition. 31 August-2 September 2015. Pasadena, California. NF1676L-20719.
  66. ^ Hyperspectral Observer for Venus Reconnaissance (HOVER). Larry W. Esposito, and the HOVER Team. EPSC Abstracts Vol. 13, EPSC-DPS2019-340-2, 2019 EPSC-DPS Joint Meeting 2019.
  67. ^ Narasimhan, T. E. (2018-12-18). "Isro to go to Venus by 2023 after Mars success, human spaceflight plans". Business Standard India. Retrieved 2018-12-18.
  68. ^ "5 Missions in 5 yrs to study Solar System, Black holes". Deccan Herald. 2019-07-19. Retrieved 2019-07-28.
  69. ^ VAMP' Key Vehicle Parameters – as of March 2015. Northrop Grumman. (PDF)
  70. ^ VAMP Air Vehicle Features And Benefits – as of March 2015. Northrop Grumman. (PDF)
  71. ^ Venera-D: Expanding our horizon of terrestrial planet climate and geology through the comprehensive exploration of Venus. Report of the Venera-D Joint Science Definition Team. 31 January 2017.
  72. ^ VICI: Venus In situ Composition Investigations. (PDF) L. Glaze, J. Garvin, N. Johnson, G. Arney, D. Atkinson, S. Atreya, A. Beck, B. Bezard, J. Blacksberg, B. Campbell, S. Clegg, D. Crisp, D. Dyar, F. Forget, M. Gilmore, D. Grinspoon, Juliane Gross, S. Guzewich, N. Izenberg, J. Johnson, W. Kiefer, D. Lawrence, S. Lebonnois, R. Lorenz, P. Mahaffy, S. Maurice, M. McCanta, A. Parsons, A. Pavlov, S. Sharma, M. Trainer, C. Webster, R. Wiens, K. Zahnle, M. Zolotov. EPSC Abstracts, Vol. 11, EPSC2017-346, 2017. European Planetary Science Congress 2017.
  73. ^ The New Frontiers Venus In Situ Atmospheric and Geochemical Explorer (VISAGE) Mission Proposal. (PDF) L.W. Esposito, D.H. Atkinson, K.H. Baines, A. Allwood, F. Altieri, S. Atreya, M. Bullock, A. Colaprete, M. Darrach, J. Day, M. Dyar, B. Ehlmann, K. Farley, J. Filiberto, D. Grinspoon, J. Head, J. Helbert, S. Madzunkov, G. Piccioni, W. Possel, M. Ravine, A. Treiman, Y. Yung, K. Zahnle. EPSC Abstracts. Vol. 11, EPSC2017-275-1, 2017. European Planetary Science Congress 2017.
  74. ^ Mission Concept: Venus in situ Explorer (VISE). Larry W. Esposito. Published by NASA. 2017.
  75. ^ Venus Multiprobe Mission. NASA. Proposed in 1994. Accessed on 21 December 2018.
  76. ^ Smrekar, Suzanne; Dyar, M. D.; et al. (eds.). Venus Origins Explorer (VOX), a Proposed New Frontier Mission (PDF). The Venus Exploration Analysis Group.
  77. ^ Venus Origins Explorer New Frontiers Proposal. Van Kane. Future Planetary Exploration. 1 October 2017.
  78. ^ Report: "NASA Will Launch a Venus Rover in 2023". Neel V. Patel, The Inverse. February 29, 2016.
  79. ^ Frank Mills (September 15, 2012). "What Venus has taught us about protecting the ozone layer". theConversation.com. Retrieved October 13, 2020.

External links[edit]