Venus

Venus is the second planet from the Sun. It is a terrestrial planet and is the closest in mass and size to its orbital neighbour Earth. Venus is notable for having the densest atmosphere of the terrestrial planets, composed mostly of carbon dioxide with a thick, global sulfuric acid cloud cover. At the surface it has a mean temperature of 737 K (464 °C; 867 °F) and a pressure of 92 times that of Earth's at sea level. These extreme conditions compress carbon dioxide into a supercritical state close to Venus's surface.

Internally, Venus has a

Venus is one of the four terrestrial planets in the Solar System, meaning that it is a rocky body like Earth. It is similar to Earth in size and mass and is often described as Earth's "sister" or "twin".^[32] Venus is close to spherical due to its slow rotation.^[33] Venus has a diameter of 12,103.6 km (7,520.8 mi)—only 638.4 km (396.7 mi) less than Earth's—and its mass is 81.5% of Earth's, making it the third-smallest planet in the Solar System. Conditions on the Venusian surface differ radically from those on Earth because its dense atmosphere is 96.5% carbon dioxide, with most of the remaining 3.5% being nitrogen.^[34] The surface pressure is 9.3 megapascals (93 bars), and the average surface temperature is 737 K (464 °C; 867 °F), above the critical points of both major constituents and making the surface atmosphere a supercritical fluid out of mainly supercritical carbon dioxide and some supercritical nitrogen.

Atmosphere and climate

Venus has a dense

Venus's atmosphere is rich in primordial noble gases compared to that of Earth.^[42] This enrichment indicates an early divergence from Earth in evolution. An unusually large comet impact^[43] or accretion of a more massive primary atmosphere from solar nebula^[44] have been proposed to explain the enrichment. However, the atmosphere is depleted of radiogenic argon, a proxy for mantle degassing, suggesting an early shutdown of major magmatism.^[45][46]

Studies have suggested that billions of years ago, Venus's atmosphere could have been much more like the one surrounding the early Earth, and that there may have been substantial quantities of liquid water on the surface.

The existence of lightning in the atmosphere of Venus has been controversial[79] since the first suspected bursts were detected by the Soviet Venera probes.^[80][81][82] In 2006–07, Venus Express clearly detected whistler mode waves, the signatures of lightning. Their intermittent appearance indicates a pattern associated with weather activity. According to these measurements, the lightning rate is at least half that on Earth,^[83] however other instruments have not detected lightning at all.^[79] The origin of any lightning remains unclear, but could originate from clouds or Venusian volcanoes.

In 2007, Venus Express discovered that a huge double

In December 2015, and to a lesser extent in April and May 2016, researchers working on Japan's Akatsuki mission observed bow-shaped objects in the atmosphere of Venus. This was considered direct evidence of the existence of perhaps the largest stationary gravity waves in the solar system.^[89][90][91]

Geography

The Venusian surface was a subject of speculation until some of its secrets were revealed by

Most Venusian surface features are named after historical and mythological women.^[103] Exceptions are Maxwell Montes, named after James Clerk Maxwell, and highland regions Alpha Regio, Beta Regio, and Ovda Regio. The last three features were named before the current system was adopted by the International Astronomical Union, the body which oversees planetary nomenclature.^[104]

The longitude of physical features on Venus is expressed relative to its prime meridian. The original prime meridian passed through the radar-bright spot at the centre of the oval feature Eve, located south of Alpha Regio.^[105] After the Venera missions were completed, the prime meridian was redefined to pass through the central peak in the crater Ariadne on Sedna Planitia.^[106][107]

The stratigraphically oldest tessera terrains have consistently lower thermal emissivity than the surrounding basaltic plains measured by Venus Express and Magellan, indicating a different, possibly a more felsic, mineral assemblage.^[26][108] The mechanism to generate a large amount of felsic crust usually requires the presence of water ocean and plate tectonics, implying that habitable condition had existed on early Venus with large bodies of water at some point.^[109] However, the nature of tessera terrains is far from certain.^[110]

Studies reported on 26 October 2023 suggest for the first time that Venus may have had

Much of the Venusian surface appears to have been shaped by volcanic activity. Venus has several times as many volcanoes as Earth, and it has 167 large volcanoes that are over 100 km (60 mi) across. The only volcanic complex of this size on Earth is the Big Island of Hawaii.^[102]: 154 More than 85,000 volcanoes on Venus were identified and mapped.^[111][112] This is not because Venus is more volcanically active than Earth, but because its crust is older and is not subject to the same erosion process. Earth's oceanic crust is continually recycled by subduction at the boundaries of tectonic plates, and has an average age of about 100 million years,^[113] whereas the Venusian surface is estimated to be 300–600 million years old.^[100][102]

Several lines of evidence point to ongoing

This massive volcanic activity is fuelled by a superheated interior, which models say could be explained by energetic collisions from when the planet was young. Impacts would have had significantly higher velocity than on Earth, both because Venus's orbit is faster due to its closer proximity to the Sun and because objects would require higher orbital eccentricities to collide with the planet.[119]

In 2008 and 2009, the first direct evidence for ongoing volcanism was observed by Venus Express, in the form of four transient localized infrared hot spots within the rift zone

Almost a thousand impact craters on Venus are evenly distributed across its surface. On other cratered bodies, such as Earth and the Moon, craters show a range of states of degradation. On the Moon, degradation is caused by subsequent impacts, whereas on Earth it is caused by wind and rain erosion. On Venus, about 85% of the craters are in pristine condition. The number of craters, together with their well-preserved condition, indicates the planet underwent a global resurfacing event 300–600 million years ago,^[100][101] followed by a decay in volcanism.^[125] Whereas Earth's crust is in continuous motion, Venus is thought to be unable to sustain such a process. Without plate tectonics to dissipate heat from its mantle, Venus instead undergoes a cyclical process in which mantle temperatures rise until they reach a critical level that weakens the crust. Then, over a period of about 100 million years, subduction occurs on an enormous scale, completely recycling the crust.^[102]

Venusian craters range from 3 to 280 km (2 to 174 mi) in diameter. No craters are smaller than 3 km, because of the effects of the dense atmosphere on incoming objects. Objects with less than a certain kinetic energy are slowed so much by the atmosphere that they do not create an impact crater.^[126] Incoming projectiles less than 50 m (160 ft) in diameter will fragment and burn up in the atmosphere before reaching the ground.^[127]

Internal structure

Without data from reflection seismology or knowledge of its moment of inertia, little direct information is available about the internal structure and geochemistry of Venus.^[128] The similarity in size and density between Venus and Earth suggests that they share a similar internal structure: a core, mantle, and crust. Like that of Earth, the Venusian core is most likely at least partially liquid because the two planets have been cooling at about the same rate,^[129] although a completely solid core cannot be ruled out.^[130] The slightly smaller size of Venus means pressures are 24% lower in its deep interior than Earth's.^[131] The predicted values for the moment of inertia based on planetary models suggest a core radius of 2,900–3,450 km.^[130] This is in line with the first observation-based estimate of 3,500 km.^[132]

The principal difference between the two planets is the lack of evidence for plate tectonics on Venus, possibly because its crust is too strong to

The lack of an intrinsic magnetic field on Venus was surprising, given that it is similar to Earth in size and was expected to contain a dynamo at its core. A dynamo requires three things: a conducting liquid, rotation, and convection. The core is thought to be electrically conductive and, although its rotation is often thought to be too slow, simulations show it is adequate to produce a dynamo.^[136][137] This implies that the dynamo is missing because of a lack of convection in Venus's core. On Earth, convection occurs in the liquid outer layer of the core because the bottom of the liquid layer is much higher in temperature than the top. On Venus, a global resurfacing event may have shut down plate tectonics and led to a reduced heat flux through the crust. This insulating effect would cause the mantle temperature to increase, thereby reducing the heat flux out of the core. As a result, no internal geodynamo is available to drive a magnetic field. Instead, the heat from the core is reheating the crust.^[138]

One possibility is that Venus has no solid inner core,

sulphur, which is unknown at present.^[138]

Another possibility is that the absence of a late, large impact on Venus (contra the Earth's "Moon-forming" impact) left the core of Venus stratified from the core's incremental formation, and without the forces to initiate/sustain convection, and thus a "geodynamo".[140]

The weak magnetosphere around Venus means that the solar wind is interacting directly with its outer atmosphere. Here, ions of hydrogen and oxygen are being created by the dissociation of water molecules from ultraviolet radiation. The solar wind then supplies energy that gives some of these ions sufficient velocity to escape Venus's gravity field. This erosion process results in a steady loss of low-mass hydrogen, helium, and oxygen ions, whereas higher-mass molecules, such as carbon dioxide, are more likely to be retained. Atmospheric erosion by the solar wind could have led to the loss of most of Venus's water during the first billion years after it formed.^[141] However, the planet may have retained a dynamo for its first 2–3 billion years, so the water loss may have occurred more recently.^[142] The erosion has increased the ratio of higher-mass deuterium to lower-mass hydrogen in the atmosphere 100 times compared to the rest of the solar system.^[143]

Orbit and rotation

Main article: Orbit of Venus

Venus orbits the Sun at an average distance of about 0.72 AU (108 million km; 67 million mi), and completes an orbit every 224.7 days. Although all planetary orbits are elliptical, Venus's orbit is currently the closest to circular, with an eccentricity of less than 0.01.^[4] Simulations of the early solar system orbital dynamics have shown that the eccentricity of the Venus orbit may have been substantially larger in the past, reaching values as high as 0.31 and possibly impacting early climate evolution.^[144]

All planets in the Solar System orbit the Sun in an

solar day on Venus is significantly shorter than the sidereal day, at 116.75 Earth days (making the Venusian solar day shorter than Mercury

's 176 Earth days — the 116-day figure is close to the average number of days it takes Mercury to slip underneath the Earth in its orbit [the number of days of Mercury's synodic orbital period]).[11] One Venusian year is about 1.92 Venusian solar days.^[151] To an observer on the surface of Venus, the Sun would rise in the west and set in the east,^[151] although Venus's opaque clouds prevent observing the Sun from the planet's surface.^[152]

Venus may have formed from the

solar nebula with a different rotation period and obliquity, reaching its current state because of chaotic spin changes caused by planetary perturbations and tidal effects on its dense atmosphere, a change that would have occurred over the course of billions of years. The rotation period of Venus may represent an equilibrium state between tidal locking to the Sun's gravitation, which tends to slow rotation, and an atmospheric tide created by solar heating of the thick Venusian atmosphere.^[153][154] The 584-day average interval between successive close approaches to Earth is almost exactly equal to 5 Venusian solar days (5.001444 to be precise),^[155] but the hypothesis of a spin-orbit resonance with Earth has been discounted.^[156]

Venus has no natural satellites.

tidal deceleration caused the Venusian moon gradually to spiral inward until it collided with Venus.^[162] If later impacts created moons, these were removed in the same way. An alternative explanation for the lack of satellites is the effect of strong solar tides, which can destabilize large satellites orbiting the inner terrestrial planets.^[157]

The orbital space of Venus has a

dust ring-cloud,^[163] with a suspected origin either from Venus–trailing asteroids,^[164] interplanetary dust migrating in waves, or the remains of the Solar System's original circumstellar disc that formed the planetary system.^[165]

Orbit in respect to Earth

Earth and Venus have a near orbital resonance of 13:8 (Earth orbits eight times for every 13 orbits of Venus).^[166] Therefore, they approach each other and reach

synodic periods of 584 days, on average.^[4] The path that Venus makes in relation to Earth viewed geocentrically draws a pentagram over five synodic periods, shifting every period by 144°. This pentagram of Venus is sometimes referred to as the petals of Venus due to the path's visual similarity to a flower.^[167]

When Venus lies between Earth and the Sun in inferior conjunction, it makes the closest approach to Earth of any planet at an average distance of 41 million km (25 million mi).^{[4][note 3][168]} Because of the decreasing eccentricity of Earth's orbit, the minimum distances will become greater over tens of thousands of years. From the year 1 to 5383, there are 526 approaches less than 40 million km (25 million mi); then, there are none for about 60,158 years.^[169]

While Venus approaches Earth the closest, Mercury is more often the closest to Earth of all planets.^[170][171] Venus has the lowest gravitational potential difference to Earth than any other planet, needing the lowest delta-v to transfer between them.^[172][173]

Tidally Venus exerts the third strongest tidal force on Earth, after the Moon and the Sun, though significantly less.^[174]

Observability

To the

inferior planet, it always lies within about 47° of the Sun.^[178]

Venus "overtakes" Earth every 584 days as it orbits the Sun.[4] As it does so, it changes from the "Evening Star", visible after sunset, to the "Morning Star", visible before sunrise. Although Mercury, the other inferior planet, reaches a maximum elongation of only 28° and is often difficult to discern in twilight, Venus is hard to miss when it is at its brightest. Its greater maximum elongation means it is visible in dark skies long after sunset. As the brightest point-like object in the sky, Venus is a commonly misreported "unidentified flying object".^[179]

Phases

Main article: Phases of Venus

As it orbits the Sun, Venus displays phases like those of the Moon in a telescopic view. The planet appears as a small and "full" disc when it is on the opposite side of the Sun (at superior conjunction). Venus shows a larger disc and "quarter phase" at its maximum elongations from the Sun, and appears at its brightest in the night sky. The planet presents a much larger thin "crescent" in telescopic views as it passes along the near side between Earth and the Sun. Venus displays its largest size and "new phase" when it is between Earth and the Sun (at inferior conjunction). Its atmosphere is visible through telescopes by the halo of sunlight refracted around it.^[178] The phases are clearly visible in a 4" telescope.^{[citation needed]} Although naked eye visibility of Venus's phases is disputed, records exist of observations of its crescent.^[180]

Daylight apparitions

When Venus is sufficiently bright with enough angular distance from the sun, it is easily observed in a clear daytime sky with the naked eye, though most people do not know to look for it.

Napoleon Bonaparte once witnessed a daytime apparition of the planet while at a reception in Luxembourg.^[182] Another historical daytime observation of the planet took place during the inauguration of the American president Abraham Lincoln in Washington, D.C., on 4 March 1865.^[183]

Transits

Main article: Transit of Venus

A

synodic period of 1.6 years, do not produce a transit of Venus above Earth. Consequently, Venus transits above Earth only occur when an inferior conjunction takes place during some days of June or December, the time where the orbits of Venus and Earth cross a straight line with the Sun.^[184]

This results in Venus transiting above Earth in a sequence of currently 8 years, 105.5 years, 8 years and 121.5 years, forming cycles of 243 years.

Historically, transits of Venus were important, because they allowed astronomers to determine the size of the

1639 with the first known observation of a Venus transit (after history's first observed planetary transit in 1631, of Mercury).^[185]

Only seven Venus transits have been observed so far, since their occurrences were calculated in the 1621 by

Captain Cook sailed to Tahiti in 1768 to record the third observed transit of Venus, which subsequently resulted in the exploration of the east coast of Australia.^[186][187]

The latest pair was

December 1882

.

The next transit will occur in December 2117 and December 2125.[189]

Ashen light

A long-standing mystery of Venus observations is the so-called ashen light—an apparent weak illumination of its dark side, seen when the planet is in the crescent phase. The first claimed observation of ashen light was made in 1643, but the existence of the illumination has never been reliably confirmed. Observers have speculated it may result from electrical activity in the Venusian atmosphere, but it could be illusory, resulting from the physiological effect of observing a bright, crescent-shaped object.^[190][81] The ashen light has often been sighted when Venus is in the evening sky, when the evening terminator of the planet is towards Earth.

Observation and exploration history

Main article: Observations and explorations of Venus

Early observation

Venus is in Earth's sky bright enough to be visible

First Babylonian dynasty indicate that the ancient Sumerians already knew that the morning and evening stars were the same celestial object.^{[192][191][193]} In the Old Babylonian period, the planet Venus was known as Ninsi'anna, and later as Dilbat.^[194] The name "Ninsi'anna" translates to "divine lady, illumination of heaven", which refers to Venus as the brightest visible "star". Earlier spellings of the name were written with the cuneiform sign si4 (= SU, meaning "to be red"), and the original meaning may have been "divine lady of the redness of heaven", in reference to the colour of the morning and evening sky.^[195]

The Chinese historically referred to the morning Venus as "the Great White" (Tàibái 太白) or "the Opener (Starter) of Brightness" (Qǐmíng 啟明), and the evening Venus as "the Excellent West One" (Chánggēng 長庚).[196]

The ancient Greeks initially believed Venus to be two separate stars:

Diogenes Laërtius argued that Parmenides (early fifth century) was probably responsible for this discovery.^[198] Though they recognized Venus as a single object, the ancient Romans continued to designate the morning aspect of Venus as Lucifer, literally "Light-Bringer", and the evening aspect as Vesper,^[199]

both of which are literal translations of their traditional Greek names.

In the second century, in his astronomical treatise

Qotb al-Din Shirazi, though this cannot be true as there were no Venus transits in Ibn Bajjah's lifetime.^{[202][note 4]}

Venus and early modern astronomy

heliocentric model and disproved Ptolemy's geocentric model

(second image).

When the Italian physicist Galileo Galilei first observed the planet with a telescope in the early 17th century, he found it showed phases like the Moon, varying from crescent to gibbous to full and vice versa. When Venus is furthest from the Sun in the sky, it shows a half-lit phase, and when it is closest to the Sun in the sky, it shows as a crescent or full phase. This could be possible only if Venus orbited the Sun, and this was among the first observations to clearly contradict the Ptolemaic geocentric model that the Solar System was concentric and centred on Earth.^[205][206]

The

1639 transit of Venus was accurately predicted by Jeremiah Horrocks and observed by him and his friend, William Crabtree, at each of their respective homes, on 4 December 1639 (24 November under the Julian calendar in use at that time).^[207]

The

Giovanni Cassini and Schröter incorrectly estimated periods of about 24 h from the motions of markings on the planet's apparent surface.^[211]

Early 20th century advances

Little more was discovered about Venus until the 20th century. Its almost featureless disc gave no hint what its surface might be like, and it was only with the development of spectroscopic and ultraviolet observations that more of its secrets were revealed.

Spectroscopic observations in the 1900s gave the first clues about the Venusian rotation.

Doppler shift of light from Venus, but found he could not detect any rotation. He surmised the planet must have a much longer rotation period than had previously been thought.^[212]

The first ultraviolet observations were carried out in the 1920s, when

Frank E. Ross found that ultraviolet photographs revealed considerable detail that was absent in visible and infrared radiation. He suggested this was due to a dense, yellow lower atmosphere with high cirrus clouds above it.^[213]

It had been noted that Venus had no discernible

tidally locked like Mercury was believed to be at the time; but other researchers had detected a significant quantity of heat coming from the planet's nightside, suggesting a quick rotation (a high surface temperature was not suspected at the time), confusing the issue.^[214]

Later work in the 1950s showed the rotation was retrograde.

Space age

Further information: List of missions to Venus

Humanity's first interplanetary spaceflight was achieved in 1961 with the robotic space probe Venera 1 of the Soviet Venera programme flying to Venus, though it lost contact en route.^[215]

Therefore, the first successful interplanetary mission was the Mariner 2 mission to Venus of the United States' Mariner programme, passing on 14 December 1962 at 34,833 km (21,644 mi) above the surface of Venus and gathering data on the planet's atmosphere.^[216][217]

Additionally radar observations of Venus were first carried out in the 1960s, and provided the first measurements of the rotation period, which were close to the actual value.^[218]

Venera 3, launched in 1966, became humanity's first probe and lander to reach and impact another celestial body other than the Moon, but could not return data as it crashed into the surface of Venus. In 1967, Venera 4 was launched and successfully deployed science experiments in the Venusian atmosphere before impacting. Venera 4 showed the surface temperature was hotter than Mariner 2 had calculated, at almost 500 °C (932 °F), determined that the atmosphere was 95% carbon dioxide (CO
₂), and discovered that Venus's atmosphere was considerably denser than Venera 4's designers had anticipated.^[219]

In an early example of space cooperation the data of Venera 4 was joined with the 1967 Mariner 5 data, analysed by a combined Soviet–American science team in a series of colloquia over the following year.^[220]

On 15 December 1970,

soft land on another planet and the first to transmit data from there back to Earth.^[221]

In 1974, Mariner 10 swung by Venus to bend its path towards Mercury and took ultraviolet photographs of the clouds, revealing the extraordinarily high wind speeds in the Venusian atmosphere. This was the first interplanetary gravity assist ever used, a technique which would be used by later probes.

Radar observations in the 1970s revealed details of the Venusian surface for the first time. Pulses of radio waves were beamed at the planet using the 300 m (1,000 ft) radio telescope at Arecibo Observatory, and the echoes revealed two highly reflective regions, designated the Alpha and Beta regions. The observations revealed a bright region attributed to mountains, which was called Maxwell Montes.^[222] These three features are now the only ones on Venus that do not have female names.^[104]

In 1975, the Soviet Venera 9 and 10 landers transmitted the first images from the surface of Venus, which were in black and white. NASA obtained additional data with the Pioneer Venus project that consisted of two separate missions:^[223] the Pioneer Venus Multiprobe and Pioneer Venus Orbiter, orbiting Venus between 1978 and 1992.^[224] In 1982 the first colour images of the surface were obtained with the Soviet Venera 13 and 14 landers. After Venera 15 and 16 operated between 1983 and 1984 in orbit, conducting detailed mapping of 25% of Venus's terrain (from the north pole to 30°N latitude), the successful Soviet Venera programme came to a close.^[225]

In 1985 the

Vega programme with its Vega 1 and Vega 2 missions carried the last entry probes and carried the first ever extraterrestrial aerobots

for the first time achieving atmospheric flight outside Earth by employing inflatable balloons.

Between 1990 and 1994, Magellan operated in orbit until deorbiting, mapping the surface of Venus. Furthermore, probes like Galileo (1990),^[226] Cassini–Huygens (1998/1999), and MESSENGER (2006/2007) visited Venus with flybys flying to other destinations. In April 2006, Venus Express, the first dedicated Venus mission by the European Space Agency (ESA), entered orbit around Venus. Venus Express provided unprecedented observation of Venus's atmosphere. ESA concluded the Venus Express mission in December 2014 deorbiting it in January 2015.^[227]

In 2010, the first successful interplanetary solar sail spacecraft IKAROS travelled to Venus for a flyby.

Active and future missions

Further information: List of missions to Venus § Future missions

As of 2023, the only active mission at Venus is Japan's Akatsuki, having achieved orbital insertion on 7 December 2015. Additionally, several flybys by other probes have been performed and studied Venus on their way, including NASA's Parker Solar Probe, and ESA's Solar Orbiter and BepiColombo.

There are currently several probes under development as well as multiple proposed missions still in their early conceptual stages.

Venus has been identified for future research as an important case for understanding:

• the origins of the solar system and Earth, and if systems and planets like ours are common or rare in the universe.
• how planetary bodies evolve from their primordial states to today's diverse objects.
• the development of conditions leading to habitable environments and life.^[230]

Search for life

Main article: Life on Venus

Speculation on the possibility of life on Venus's surface decreased significantly after the early 1960s when it became clear that conditions were extreme compared to those on Earth. Venus's extreme temperatures and atmospheric pressure make water-based life, as currently known, unlikely.

Some scientists have speculated that thermoacidophilic extremophile microorganisms might exist in the cooler, acidic upper layers of the Venusian atmosphere.^{[231][232][233]} Such speculations go back to 1967, when Carl Sagan and Harold J. Morowitz suggested in a Nature article that tiny objects detected in Venus's clouds might be organisms similar to Earth's bacteria (which are of approximately the same size):

While the surface conditions of Venus make the hypothesis of life there implausible, the clouds of Venus are a different story altogether. As was pointed out some years ago, water, carbon dioxide and sunlight—the prerequisites for photosynthesis—are plentiful in the vicinity of the clouds.^[234]

In August 2019, astronomers led by Yeon Joo Lee reported that long-term pattern of absorbance and

light absorbance is almost identical to that of micro-organisms in Earth's clouds. Similar conclusions have been reached by other studies.^[235]

In September 2020, a team of astronomers led by Jane Greaves from Cardiff University announced the likely detection of phosphine, a gas not known to be produced by any known chemical processes on the Venusian surface or atmosphere, in the upper levels of the planet's clouds.^{[236][60][59][237][238]} One proposed source for this phosphine is living organisms.^[239] The phosphine was detected at heights of at least 30 miles (48 km) above the surface, and primarily at mid-latitudes with none detected at the poles. The discovery prompted NASA administrator Jim Bridenstine to publicly call for a new focus on the study of Venus, describing the phosphine find as "the most significant development yet in building the case for life off Earth".^[240][241]

Subsequent analysis of the data-processing used to identify phosphine in the atmosphere of Venus has raised concerns that the detection-line may be an artefact. The use of a 12th-order polynomial fit may have amplified noise and generated a false reading (see

statistically significant detection of phosphine.^{[243][244][245]}

Members of the team around Greaves, are working as part of a project by the

MIT to send with the rocket company Rocket Lab the first private interplanetary space craft, to look for organics by entering the atmosphere of Venus with a probe, set to launch in January 2025.^[246]

Planetary protection

The Committee on Space Research is a scientific organisation established by the International Council for Science. Among their responsibilities is the development of recommendations for avoiding interplanetary contamination. For this purpose, space missions are categorized into five groups. Due to the harsh surface environment of Venus, Venus has been under the planetary protection category two.^[247] This indicates that there is only a remote chance that spacecraft-borne contamination could compromise investigations.

Human presence

Main article: List of missions to Venus

Venus is the place of the first interplanetary human presence, mediated through robotic missions, with the first successful landings on another planet and extraterrestrial body other than the Moon. Currently in orbit is Akatsuki, and other probes routinely use Venus for gravity assist manoeuvres capturing some data about Venus on the way.^[248]

The only nation that has sent lander probes to the surface of Venus has been the Soviet Union,^{[note 5]} which has been used by Russian officials to call Venus a "Russian planet".^[249][250]

Crewed flight

Studies of routes for crewed missions to Mars have since the 1960s proposed opposition missions instead of direct conjunction missions with Venus gravity assist flybys, demonstrating that they should be quicker and safer missions to Mars, with better return or abort flight windows, and less or the same amount of radiation exposure from the flight as direct Mars flights.^[251][252]

Early in the space age the Soviet Union and the United States proposed the TMK-MAVR and Manned Venus flyby crewed flyby missions to Venus, though they were never realized.

Habitation

See also: Colonization of Venus and Floating cities and islands in fiction § Venus

High Altitude Venus Operational Concept (HAVOC)

crewed floating outpost on Venus

While the surface conditions of Venus are inhospitable, the atmospheric pressure, temperature, and solar and cosmic radiation 50 km above the surface are similar to those at Earth's surface.^[58][57] With this in mind, Soviet engineer Sergey Zhitomirskiy (Сергей Житомирский, 1929–2004) in 1971^[253][254] and NASA aerospace engineer Geoffrey A. Landis in 2003^[255] suggested the use of aerostats for crewed exploration and possibly for permanent "floating cities" in the Venusian atmosphere, an alternative to the popular idea of living on planetary surfaces such as Mars.^[256][257] Among the many engineering challenges for any human presence in the atmosphere of Venus are the corrosive amounts of sulfuric acid in the atmosphere.^[255]

NASA's High Altitude Venus Operational Concept is a mission concept that proposed a crewed aerostat design.

In culture

Main article: Venus in culture

Venus is a primary feature of the night sky, and so has been of remarkable importance in mythology, astrology and fiction throughout history and in different cultures.

The English name of Venus was originally the

Akkadian religion), all of whom were associated with the planet.^[261][262] The weekday of the planet and these goddesses is Friday, named after the Germanic goddess Frigg

, who has been associated with the Roman goddess Venus.

Several hymns praise Inanna in her role as the goddess of the planet Venus.

Inanna and Shukaletuda and Inanna's Descent into the Underworld appear to parallel the motion of the planet Venus.^[191] In Inanna and Shukaletuda, Shukaletuda is described as scanning the heavens in search of Inanna, possibly searching the eastern and western horizons.^[263] In the same myth, while searching for her attacker, Inanna herself makes several movements that correspond with the movements of Venus in the sky.^[191]

The

Phōsphoros (Φωσϕόρος), meaning "light-bringer" (whence the element phosphorus; alternately Ēōsphoros (Ἠωσϕόρος), meaning "dawn-bringer"), for the morning star, and Hesperos (Ἕσπερος), meaning "Western one", for the evening star,^[267] both children of dawn Eos and therefore grandchildren of Aphrodite. Though by the Roman era they were recognized as one celestial object, known as "the star of Venus", the traditional two Greek names continued to be used, though usually translated to Latin as Lūcifer and Vesper.^[267][268]

Classical poets such as

Alfred Lord Tennyson and William Wordsworth wrote odes to it.^[270]

In India, Shukra Graha ("the planet Shukra") is named after the powerful saint Shukra.

Bhrgu, preceptor of the Daityas, and guru of the Asuras.^[272]

The word Shukra is also associated with semen, or generation.

Venus is known as Kejora in

Malaysian Malay

.

In Chinese the planet is called Jīn-xīng (金星), the golden planet of the

Five elements.^{[273][274][275][276]}

The

Maya considered Venus to be the most important celestial body after the Sun and Moon. They called it Chac ek,^[277] or Noh Ek', "the Great Star".^[278] The cycles of Venus were important to their calendar and were described in some of their books such as Maya Codex of Mexico and Dresden Codex. The Estrella Solitaria ("Lone Star") Flag of Chile

depicts Venus.

Modern culture

See also: Venus in fiction

The impenetrable Venusian cloud cover gave science fiction writers free rein to speculate on conditions at its surface; all the more so when early observations showed that not only was it similar in size to Earth, it possessed a substantial atmosphere. Closer to the Sun than Earth, the planet was often depicted as warmer, but still habitable by humans.^[279] The genre reached its peak between the 1930s and 1950s, at a time when science had revealed some aspects of Venus, but not yet the harsh reality of its surface conditions. Findings from the first missions to Venus showed reality to be quite different and brought this particular genre to an end.^[280] As scientific knowledge of Venus advanced, science fiction authors tried to keep pace, particularly by conjecturing human attempts to terraform Venus.^[281]

Symbols

Main article:

Venus symbol

The symbol of a circle with a small cross beneath is the so-called

heteronormatively, describing women and men stereotypically as being so different that they can be understood as coming from different planets, an understanding popularized in 1992 by the book titled Men Are from Mars, Women Are from Venus.^[285][286]

The Venus symbol was also used in Western alchemy representing the element copper (like the symbol of Mercury is also the symbol of the element mercury),^[283][284] and since polished copper has been used for mirrors from antiquity the symbol for Venus has sometimes been called Venus mirror, representing the mirror of the goddess, although this origin has been discredited as an unlikely origin.^[283][284]

Besides the Venus symbol, many other symbols have been associated with Venus, other common ones are the crescent or particularly the star, as with the Star of Ishtar.^{[citation needed]}

See also

• Outline of Venus
• Physical properties of planets in the Solar System
• Venus zone

Notes

1. ^ Misstated as "Ganiki Chasma" in the press release and scientific publication.^[121]
2. ^ The equatorial speed of Earth is given as both about 1674.4 km/h and 1669.8 km/h by reliable sources. The simplest way to determine the correct figure is to multiply Earth's radius of 6378137 m (WGS84) and Earth's angular speed, 7.2921150×10⁻⁵ rad/s,^[146] yielding 465.1011 m/s = 1674.364 km/h. The incorrect figure of 1669.8 km/h is obtained by dividing Earth's equatorial circumference by 24 h. But the correct speed must be relative to inertial space, so the stellar day of 86164.098903691 s/3600 = 23.934472 h (23 h 56 m 4.0989 s) must be used.^[147] Thus 2π(6378.137 km)/23.934472 h = 1674.364 km/h.^[148]
3. ^ It is important to be clear about the meaning of "closeness". In the astronomical literature, the term "closest planets" often refers to the two planets that approach each other the most closely. In other words, the orbits of the two planets approach each other most closely. However, this does not mean that the two planets are closest over time. Essentially because Mercury is closer to the Sun than Venus, Mercury spends more time in proximity to Earth; it could, therefore, be said that Mercury is the planet that is "closest to Earth when averaged over time". However, using this time-average definition of "closeness", it turns out that Mercury is the closest planet to all other planets in the solar system. For that reason, arguably, the proximity-definition is not particularly helpful. An episode of the BBC Radio 4 programme "More or Less" explains the different notions of proximity well.^[168]
4. ^ Several claims of transit observations made by mediaeval Islamic astronomers have been shown to be sunspots.^[203] Avicenna did not record the date of his observation. There was a transit of Venus within his lifetime, on 24 May 1032, although it is questionable whether it would have been visible from his location.^[204]
5. atmospheric entry probes
   only briefly signals were received from the surface.

References

1. ^ "Venusian". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 23 March 2020.
   "Venusian". Merriam-Webster.com Dictionary.
2. ^ "Cytherean". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
3. ^ "Venerean, Venerian". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
4. ^ ^{a b c d e f g h i j k l} Williams, David R. (25 November 2020). "Venus Fact Sheet". NASA Goddard Space Flight Center. Archived from the original on 11 May 2018. Retrieved 15 April 2021.
5. J2000
   epoch.
6. ^
   Bibcode:1994A&A...282..663S
   .
7. doi:10.1051/0004-6361/201219011
   . A133.
8. ^
   doi:10.1007/s10569-007-9072-y
   .
9. doi:10.1006/icar.1999.6086. Archived from the original
   (PDF) on 26 May 2010.
10. ^ "Planets and Pluto: Physical Characteristics". NASA. 5 November 2008. Archived from the original on 7 September 2006. Retrieved 26 August 2015.
11. ^ ^{a b} "Planetary Facts". The Planetary Society. Archived from the original on 11 May 2012. Retrieved 20 January 2016.
12. S2CID 232092194
    .
13. ^ "Report on the IAU/IAG Working Group on cartographic coordinates and rotational elements of the planets and satellites". International Astronomical Union. 2000. Archived from the original on 12 May 2020. Retrieved 12 April 2007.
14. S2CID 119307693
    .
15. doi:10.1016/j.icarus.2016.02.048. Archived
    (PDF) from the original on 22 September 2017. Retrieved 25 June 2019.
16. ^ "Atmospheres and Planetary Temperatures". American Chemical Society. 18 July 2013. Archived from the original on 27 January 2023. Retrieved 3 January 2023.
17. ^
    S2CID 208513344. Archived
    from the original on 5 December 2021. Retrieved 20 November 2021.
18. ^
    S2CID 69912809
    .
19. ^ "Encyclopedia – the brightest bodies". IMCCE. Archived from the original on 24 July 2023. Retrieved 29 May 2023.
20. ^ Andrews, Roy George (27 May 2024). "Rivers of Lava on Venus Reveal a More Volcanically Active Planet - New software let scientists re-examine old radar images, providing some of the strongest evidence yet that volcanoes continue to reshape the hellish planet". The New York Times. Archived from the original on 27 May 2024. Retrieved 28 May 2024.
21. doi:10.1038/s41550-024-02272-1. Archived
    from the original on 27 May 2024. Retrieved 28 May 2024.
22. ^ "Moons". NASA Solar System Exploration. Archived from the original on 19 October 2019. Retrieved 26 August 2019.
23. ^ ^{a b} Chang, Kenneth (26 October 2023). "Billions of Years Ago, Venus May Have Had a Key Earthlike Feature – A new study makes the case that the solar system's hellish second planet once may have had plate tectonics that could have made it more hospitable to life". The New York Times. Archived from the original on 26 October 2023. Retrieved 27 October 2023.
24. ^
    S2CID 264530764. Archived
    from the original on 27 October 2023. Retrieved 27 October 2023.
25. OCLC 39464951
    .
26. ^
    S2CID 45474562
    .
27. ^ Shiga, David (10 October 2007). "Did Venus's ancient oceans incubate life?". New Scientist. Archived from the original on 24 March 2009. Retrieved 17 September 2017.
28. ^ Lawrence, Pete (2005). "In Search of the Venusian Shadow". Digitalsky.org.uk. Archived from the original on 11 June 2012. Retrieved 13 June 2012.
29. ^ Walker, John. "Viewing Venus in Broad Daylight". Fourmilab Switzerland. Archived from the original on 29 March 2017. Retrieved 19 April 2017.
30. ^ ^{a b} Newitz, Annalee (11 December 2013). "Here's Carl Sagan's original essay on the dangers of climate change". Gizmodo. Archived from the original on 3 September 2021. Retrieved 3 September 2021.
31. ^ ^{a b} Dorminey, Bruce (31 December 2018). "Galaxy May Be Littered With Dead Aliens Blindsided By Natural Climate Change". Forbes. Archived from the original on 21 April 2023. Retrieved 21 April 2023.
32. ISBN 978-3-540-00431-8
    .
33. Squyres, Steven W. (2016). "Venus". Encyclopædia Britannica Online. Archived
    from the original on 28 April 2014. Retrieved 7 January 2016.
34. ^ Darling, David. "Venus". Encyclopedia of Science. Dundee, Scotland. Archived from the original on 31 October 2021. Retrieved 24 March 2022.
35. ^
    S2CID 133864520. Archived
    (PDF) from the original on 4 May 2019. Retrieved 11 August 2023.
36. ISBN 978-0-12-415845-0. Archived
    from the original on 29 September 2021. Retrieved 12 January 2016.
37. ^ "Venus: Facts & Figures". NASA. Archived from the original on 29 September 2006. Retrieved 12 April 2007.
38. ^ "Venus". Case Western Reserve University. 13 September 2006. Archived from the original on 26 April 2012. Retrieved 21 December 2011.
39. ISBN 978-0-12-446744-6
    .
40. S2CID 17893191. Archived from the original
    (PDF) on 20 September 2019. Retrieved 27 July 2009.
41. ^ "The Planet Venus". Archived from the original on 7 August 2021. Retrieved 17 August 2021.
42. ISSN 0016-7037. Archived
    from the original on 29 September 2021. Retrieved 14 July 2020.
43. S2CID 4357750. Archived
    from the original on 29 September 2021. Retrieved 14 July 2020.
44. ISSN 0019-1035
    .
45. ISSN 2156-2202
    .
46. ISSN 0019-1035
    .
47. ^ Ernst, Richard (3 November 2022). "Venus was once more Earth-like, but climate change made it uninhabitable". The Conversation. Archived from the original on 21 April 2023. Retrieved 21 April 2023.
48. ISSN 2169-9097
    .
49. PMID 28408771
    .
50. Bibcode:2007DPS....39.6109G
    .
51. ^ Steigerwald, Bill (2 November 2022). "NASA Study: Massive Volcanism May Have Altered Ancient Venus' Climate". NASA. Archived from the original on 10 May 2023. Retrieved 5 May 2023.
52. PMID 11538226. Archived
    from the original on 7 December 2019. Retrieved 25 June 2019.
53. ^ Tillman, Nola Taylor (18 October 2018). "Venus' Atmosphere: Composition, Climate and Weather". Space.com. Archived from the original on 9 May 2023. Retrieved 9 May 2023.
54. ^ Mullen, Leslie (13 November 2002). "Venusian Cloud Colonies". Astrobiology Magazine. Archived from the original on 16 August 2014.
55. Bibcode:2003JBIS...56..250L. NASA/TM—2003-212310. Archived from the original
    (PDF) on 7 August 2011.
56. doi:10.1016/S0032-0633(99)00036-7
    .
57. ^
    S2CID 244168415
    .
58. ^
    S2CID 208513344
    .
59. ^ ^{a b} Drake, Nadia (14 September 2020). "Possible sign of life on Venus stirs up heated debate". National Geographic. Archived from the original on 14 September 2020. Retrieved 14 September 2020.
60. ^
    S2CID 221655755. Archived
    from the original on 14 September 2020. Retrieved 14 September 2020.
61. S2CID 231699227
    .
62. S2CID 229020261. Archived
    from the original on 26 December 2021. Retrieved 29 January 2023.
63. S2CID 224803085. Archived
    from the original on 16 January 2022. Retrieved 29 January 2023.
64. Bibcode:1979CosRe..17..232M
    .
65. ^
    S2CID 4369293
    .
66. doi:10.1016/j.pss.2006.04.019
    .
67. ^ Siegel, Ethan (14 July 2021). "This Is Why Venus Is The Brightest, Most Extreme Planet We Can See". Forbes. Archived from the original on 11 June 2023. Retrieved 11 June 2023.
68. ^ Davis, Margaret (14 July 2021). "Why Is Venus So Bright? Here's How Its Proximity to Earth, Highly Reflected Clouds Affects It". Science Times. Archived from the original on 13 December 2022. Retrieved 11 June 2023.
69. ^ "Venus and Earth: worlds apart – Transit of Venus blog". ESA Blog Navigator – Navigator page for active ESA blogs. 31 May 2012. Archived from the original on 11 June 2023. Retrieved 11 June 2023.
70. JSTOR 3960800
    . 100 watts per square meter ... 14,000 lux ... corresponds to ... daytime with overcast clouds
71. ISSN 1520-0469
    .
72. PMID 20448159
    .
73. S2CID 15670045. Archived
    (PDF) from the original on 3 October 2018. Retrieved 21 August 2007.
74. ^ "Interplanetary Seasons". NASA Science. NASA. 19 June 2000. Archived from the original on 14 April 2021. Retrieved 14 April 2021.
75. S2CID 13338382. Archived
    from the original on 29 September 2021. Retrieved 2 December 2019.
76. ISBN 978-0-521-76573-2. Archived
    from the original on 23 June 2016. Retrieved 18 October 2015.
77. ^ Otten, Carolyn Jones (2004). ""Heavy metal" snow on Venus is lead sulfide". Washington University in St. Louis. Archived from the original on 15 April 2008. Retrieved 21 August 2007.
78. ^
    S2CID 198179774
    .
79. ^
    ISSN 2197-4284
    .
80. Bibcode:1980CosRe..18..325K
    .
81. ^
    doi:10.1016/0273-1177(90)90174-X. Archived
    from the original on 8 December 2015. Retrieved 10 September 2015.
82. National Space Science Data Center. NASA. Archived
    from the original on 23 May 2019. Retrieved 10 September 2015.
83. S2CID 4418778. Archived from the original
    (PDF) on 4 March 2016. Retrieved 10 September 2015.
84. S2CID 129514118
    .
85. ^ Staff (28 November 2007). "Venus offers Earth climate clues". BBC News. Archived from the original on 11 January 2009. Retrieved 29 November 2007.
86. ^ "ESA finds that Venus has an ozone layer too". European Space Agency. 6 October 2011. Archived from the original on 27 January 2012. Retrieved 25 December 2011.
87. ^ "When A Planet Behaves Like A Comet". European Space Agency. 29 January 2013. Archived from the original on 2 May 2019. Retrieved 31 January 2013.
88. ^ Kramer, Miriam (30 January 2013). "Venus Can Have 'Comet-Like' Atmosphere". Space.com. Archived from the original on 3 May 2019. Retrieved 31 January 2013.
89. doi:10.1038/ngeo2873
    .
90. ^ Rincon, Paul (16 January 2017). "Venus wave may be Solar System's biggest". BBC News. Archived from the original on 17 January 2017. Retrieved 17 January 2017.
91. ^ Chang, Kenneth (16 January 2017). "Venus Smiled, With a Mysterious Wave Across Its Atmosphere". The New York Times. Archived from the original on 15 July 2017. Retrieved 17 January 2017.
92. ISBN 978-0-12-415845-0. Archived
    from the original on 29 September 2021. Retrieved 12 January 2016.
93. S2CID 12832924
    .
94. doi:10.1006/icar.2000.6570. Archived from the original
    (PDF) on 23 October 2003.
95. S2CID 21736261
    .
96. ISBN 978-1-4262-0121-9. Archived
    from the original on 16 July 2017. Retrieved 20 April 2017.
97. ISBN 978-0-7167-2379-0
    .
98. ^ National Geographic (2024) Venus is volcanically alive
99. ^ The New York Times (27 May 2024) Rivers of Lava on Venus Reveal a More Volcanically Active Planet
100. ^
     S2CID 862354
     .
101. ^
     S2CID 127759323. Archived
     from the original on 16 September 2020. Retrieved 25 June 2019.
102. ^
     ISBN 978-0-521-47770-3
     . Retrieved 30 January 2023.
103. Bibcode:1991pggp.rept..490B. Archived
     (PDF) from the original on 13 May 2011. Retrieved 12 July 2009.
104. ^ ^{a b} Young, Carolynn, ed. (1 August 1990). The Magellan Venus Explorer's Guide. California: Jet Propulsion Laboratory. p. 93. Archived from the original on 4 December 2016. Retrieved 13 January 2016.
105. S2CID 189850694
     .
106. doi:10.1007/s10569-007-9072-y
     .
107. ^ Young, Carolynn, ed. (1 August 1990). The Magellan Venus Explorer's Guide. California: Jet Propulsion Laboratory. pp. 99–100. Archived from the original on 4 December 2016. Retrieved 13 January 2016.
108. ISSN 1944-8007
     .
109. ^ Petkowski, Janusz; Seager, Sara (18 November 2021). "Did Venus ever have oceans?". Venus Cloud Life – MIT. Archived from the original on 13 April 2023. Retrieved 13 April 2023.
110. S2CID 126225959
     .
111. ^ "A new catalog pinpoints volcanic cones in the best available surface images of Venus – those gathered 30 years ago by NASA's Magellan spacecraft". skyandtelescope.org. Archived from the original on 16 April 2023. Retrieved 16 April 2023.
112. S2CID 257745255
     . With the Magellan synthetic-aperture radar full-resolution radar map left- and right-look global mosaics at 75 m-per-pixel resolution, we developed a global catalogue of volcanoes on Venus that contains ~85,000 edifices, ~99% of which are <5 km in diameter. We find that Venus hosts far more volcanoes than previously mapped, and that although they are distributed across virtually the entire planet, size–frequency distribution analysis reveals a relative lack of edifices in the 20–100 km diameter range, which could be related to magma availability and eruption rate.
113. ISBN 978-3-540-34143-7
     . Retrieved 30 January 2023.
114. ^ Bauer, Markus (3 December 2012). "Have Venusian volcanoes been caught in the act?". European Space Agency. Archived from the original on 14 April 2021. Retrieved 14 April 2021.
115. doi:10.1029/1998JE000619
     .
116. S2CID 59323909
     .
117. ^ Hall, Sannon (9 January 2020). "Volcanoes on Venus Might Still Be Smoking - Planetary science experiments on Earth suggest that the sun's second planet might have ongoing volcanic activity". The New York Times. Archived from the original on 9 January 2020. Retrieved 10 January 2020.
118. PMID 31922004
     .
119. ^ "Early, Energetic Collisions Could Have Fueled Venus Volcanism: Study | Sci.News". 20 July 2023. Archived from the original on 21 July 2023. Retrieved 21 July 2023.
120. USGS Astrogeology Science Center. Archived
     from the original on 13 October 2018. Retrieved 14 April 2021.
121. ^ ^{a b} Lakdawalla, Emily (18 June 2015). "Transient hot spots on Venus: Best evidence yet for active volcanism". The Planetary Society. Archived from the original on 20 June 2015. Retrieved 20 June 2015.
122. ^ "Hot lava flows discovered on Venus". European Space Agency. 18 June 2015. Archived from the original on 19 June 2015. Retrieved 20 June 2015.
123. S2CID 16309185
     .
124. ^ Kluger, Jeffrey (17 March 2023). "Why the Discovery of an Active Volcano on Venus Matters". Time. Archived from the original on 19 March 2023. Retrieved 19 March 2023.
125. doi:10.1016/j.icarus.2009.03.036. Archived
     (PDF) from the original on 19 December 2019. Retrieved 15 December 2018.
126. doi:10.1006/icar.1994.1180
     .
127. ISBN 978-0-8053-8734-6
     .
128. Bibcode:1982LPSC...12.1507G
     .
129. ISBN 978-1-4020-5233-0
     .
130. ^
     S2CID 134766723. Archived
     (PDF) from the original on 9 May 2020. Retrieved 3 May 2021.
131. doi:10.1016/j.icarus.2012.01.007. Archived
     from the original on 29 September 2021. Retrieved 17 January 2016.
132. ^ O'Callaghan, Jonathan (29 April 2021). "We've measured the size of Venus's planetary core for the first time". New Scientist. Archived from the original on 2 May 2021. Retrieved 2 May 2021.
133. S2CID 13293506
     .
134. Bibcode:1969CosRe...7..675D
     .
135. ISBN 978-0-521-45714-9
     .
136. ISBN 978-1-4020-4520-2. Archived
     from the original on 14 July 2010. Retrieved 19 July 2006.
137. doi:10.1016/S0012-821X(02)01126-3. Archived
     (PDF) from the original on 16 August 2017. Retrieved 6 November 2018.
138. ^
     ISSN 0091-7613. Archived
     (PDF) from the original on 1 October 2018. Retrieved 28 June 2009.
139. doi:10.1029/96GL01589
     .
140. S2CID 119487513
     .
141. S2CID 1242297
     .
142. Bibcode:2019EGUGA..2118876O
     . 18876.
143. S2CID 36740141
     .
144. doi:10.3847/PSJ/abae63
     .
145. ^ "The length of a day on Venus is always changing – Space". EarthSky. 5 May 2021. Archived from the original on 28 April 2023. Retrieved 28 April 2023.
146. ^ Petit, Gérard; Luzum, Brian (eds.). "IERS Conventions (2010)". IERS. p. 19. Archived from the original on 30 September 2019. Retrieved 16 April 2021.
147. IERS (13 March 2021). "Useful Constants". L'Observatoire de Paris. Archived
     from the original on 11 March 2019. Retrieved 16 April 2021.
148. ^ Earl, Michael A. "Rotation Speed". Canadian Astronomy, Satellite Tracking and Optical Research (CASTOR). Archived from the original on 17 July 2019. Retrieved 16 April 2021.
149. ISBN 978-0-521-63280-5
     . Retrieved 31 January 2023.
150. ^ "Could Venus Be Shifting Gear?". Venus Express. European Space Agency. 10 February 2012. Archived from the original on 24 January 2016. Retrieved 7 January 2016.
151. ^ ^{a b} "Space Topics: Compare the Planets". The Planetary Society. Archived from the original on 18 February 2006. Retrieved 12 January 2016.
152. ISBN 978-0-521-80724-1. Archived
     from the original on 3 August 2020. Retrieved 17 September 2017.
153. doi:10.1016/S0019-1035(03)00042-3. Archived
     (PDF) from the original on 27 September 2019. Retrieved 9 September 2006.
154. doi:10.1016/S0019-1035(03)00043-5. Archived
     (PDF) from the original on 2 May 2019. Retrieved 9 September 2006.
155. doi:10.1016/0019-1035(69)90068-2
     .
156. doi:10.1086/182975
     .
157. ^
     S2CID 15252548
     .
158. doi:10.1111/j.1365-2966.2004.07994.x
     .
159. S2CID 118535095
     .
160. S2CID 118661720
     .
161. ^ Musser, George (10 October 2006). "Double Impact May Explain Why Venus Has No Moon". Scientific American. Archived from the original on 26 September 2007. Retrieved 7 January 2016.
162. ^ Tytell, David (10 October 2006). "Why Doesn't Venus Have a Moon?". Sky & Telescope. Archived from the original on 24 October 2016. Retrieved 7 January 2016.
163. ^ Frazier, Sarah (16 April 2021). "NASA's Parker Solar Probe Sees Venus Orbital Dust Ring". NASA. Archived from the original on 22 August 2022. Retrieved 21 January 2023.
164. ^ Garner, Rob (12 March 2019). "What Scientists Found After Sifting Through Dust in the Solar System". NASA. Archived from the original on 1 January 2023. Retrieved 21 January 2023.
165. ^ Rehm, Jeremy (15 April 2021). "Parker Solar Probe Captures First Complete View of Venus Orbital Dust Ring". JHUAPL. Archived from the original on 21 January 2023. Retrieved 21 January 2023.
166. S2CID 117795811
     .
167. ^ Ottewell, Guy (7 January 2022). "The 5 petals of Venus and its 8-year cycle". EarthSky. Archived from the original on 22 February 2022. Retrieved 17 March 2022.
168. ^
     David A. Rothery
     , professor of planetary geosciences at the Open University.
169. ^ "Venus Close Approaches to Earth as predicted by Solex 11". Archived from the original on 9 August 2012. Retrieved 19 March 2009. Numbers generated by Solex
170. S2CID 241077611
     .
171. doi:10.1063/PT.6.3.20190312a
     .
172. ISSN 0022-4650
     .
173. ^ Taylor, Chris (9 July 2020). "Welcome to Cloud City: The case for going to Venus, not Mars". Mashable. Archived from the original on 21 October 2022. Retrieved 21 October 2022.
174. ^ "Interplanetary Low Tide". Science Mission Directorate. 3 May 2000. Archived from the original on 4 June 2023. Retrieved 25 June 2023.
175. ISBN 978-1-55209-302-3. Archived
     from the original on 29 September 2021. Retrieved 12 January 2016.
176. ^ Mallama, A. (2011). "Planetary magnitudes". Sky & Telescope. 121 (1): 51–56.
177. ^ Flanders, Tony (25 February 2011). "See Venus in Broad Daylight!". Sky & Telescope. Archived from the original on 11 September 2012. Retrieved 11 January 2016.
178. ^ ^{a b} Espenak, Fred (1996). "Venus: Twelve year planetary ephemeris, 1995–2006". NASA Reference Publication 1349. NASA/Goddard Space Flight Center. Archived from the original on 17 August 2000. Retrieved 20 June 2006.
179. ^ "Identifying UFOs". Night Sky Network. Astronomical Society of the Pacific. Archived from the original on 10 April 2021. Retrieved 10 April 2021.
180. ^ Goines, David Lance (18 October 1995). "Inferential Evidence for the Pre-telescopic Sighting of the Crescent Venus". Goines.net. Archived from the original on 4 May 2021. Retrieved 19 April 2017.
181. ^ "Viewing Venus in Broad Daylight". www.fourmilab.ch. Archived from the original on 15 November 2021. Retrieved 17 July 2023.
182. ^ Chatfield, Chris (2010). "The Solar System with the naked eye". The Gallery of Natural Phenomena. Archived from the original on 13 June 2015. Retrieved 19 April 2017.
183. ^ Gaherty, Geoff (26 March 2012). "Planet Venus Visible in Daytime Sky Today: How to See It". Space.com. Archived from the original on 19 April 2017. Retrieved 19 April 2017.
184. ^ "2004 and 2012 Transits of Venus". NASA. 8 June 2004. Archived from the original on 2 May 2023. Retrieved 2 May 2023.
185. ^ Kollerstrom, Nicholas (1998). "Horrocks and the Dawn of British Astronomy". University College London. Archived from the original on 26 June 2013. Retrieved 11 May 2012.
186. S2CID 186212060. Archived
     from the original on 9 May 2019. Retrieved 8 January 2008.
187. S2CID 59314888
     .
188. ^ Boyle, Alan (5 June 2012). "Venus transit: A last-minute guide". NBC News. Archived from the original on 18 June 2013. Retrieved 11 January 2016.
189. ^ Espenak, Fred (2004). "Transits of Venus, Six Millennium Catalog: 2000 BCE to 4000 CE". Transits of the Sun. NASA. Archived from the original on 19 March 2012. Retrieved 14 May 2009.
190. Bibcode:2000JBAA..110..325B
     .
191. ^
     ISSN 1971-8608. Archived
     from the original on 24 December 2019. Retrieved 28 December 2017.
192. S2CID 121539390
     .
193. ^ Hobson, Russell (2009). The Exact Transmission of Texts in the First Millennium B.C.E. (PDF) (Ph.D.). University of Sydney, Department of Hebrew, Biblical and Jewish Studies. Archived (PDF) from the original on 29 February 2012. Retrieved 26 December 2015.
194. ^ Enn Kasak, Raul Veede. Understanding Planets in Ancient Mesopotamia. Folklore Vol. 16. Mare Kõiva & Andres Kuperjanov, Eds. ISSN 1406-0957
195. ^ Heimpel, W. (1982). "A catalogue of Near Eastern Venus deities". Syro-Mesopotamian Studies. 4 (3). Undena Publications: 9–22.
196. ISBN 978-0-521-05801-8
     .
197. ^ Pliny the Elder (1991). Natural History II:36–37. Translated by Healy, John F. Harmondsworth, Middlesex, UK: Penguin. pp. 15–16.
198. ISBN 978-0-674-53918-1. Archived
     from the original on 9 June 2016. Retrieved 28 December 2015.
199. JSTOR 4433390
     .
200. S2CID 120700705
     .
201. ^ "AVICENNA viii. Mathematics and Physical Sciences". Encyclopædia Iranica. Archived from the original on 20 February 2020. Retrieved 4 March 2016.
202. ISBN 978-1-4020-0657-9
     .
203. ISBN 978-0-387-92790-9. Archived
     from the original on 26 November 2016. Retrieved 18 May 2016.
204. ISBN 978-1-329-00342-2. Archived
     from the original on 25 November 2016. Retrieved 18 May 2016.
205. S2CID 117985979
     .
206. ISBN 978-0-08-043751-4
     .
207. S2CID 162838538. Archived
     (PDF) from the original on 19 May 2016. Retrieved 10 May 2012.
208. doi:10.1017/S1743921305001390
     .
209. ^ "Mikhail Vasilyevich Lomonosov". Encyclopædia Britannica Online. Archived from the original on 25 July 2008. Retrieved 12 July 2009.
210. S2CID 123671250
     .
211. doi:10.1093/mnras/2.11.78d. Archived
     from the original on 11 July 2020. Retrieved 25 August 2019.
212. doi:10.1002/asna.19031630303. Archived
     from the original on 27 October 2020. Retrieved 4 May 2020.
213. doi:10.1086/143130
     .
214. Bibcode:1934PA.....42..165M
     .
215. ^ Mitchell, Don (2003). "Inventing The Interplanetary Probe". The Soviet Exploration of Venus. Archived from the original on 12 October 2018. Retrieved 27 December 2007.
216. doi:10.1086/146433
     .
217. ^ Jet Propulsion Laboratory (1962). Mariner-Venus 1962 Final Project Report (PDF) (Report). SP-59. NASA. Archived (PDF) from the original on 11 February 2014. Retrieved 7 July 2017.
218. S2CID 21133097
     .
219. ^ Mitchell, Don (2003). "Plumbing the Atmosphere of Venus". The Soviet Exploration of Venus. Archived from the original on 30 September 2018. Retrieved 27 December 2007.
220. ^ "Report on the Activities of the COSPAR Working Group VII". Preliminary Report, COSPAR Twelfth Plenary Meeting and Tenth International Space Science Symposium. Prague, Czechoslovakia: National Academy of Sciences. 11–24 May 1969. p. 94.
221. ^ "Science: Onward from Venus". Time. 8 February 1971. Archived from the original on 21 December 2008. Retrieved 2 January 2013.
222. S2CID 32590584
     .
223. S2CID 122107496
     .
224. ^ Williams, David R. (6 January 2005). "Pioneer Venus Project Information". NASA/Goddard Space Flight Center. Archived from the original on 15 May 2019. Retrieved 19 July 2009.
225. ISBN 978-0-521-03373-2. Archived
     from the original on 29 September 2021. Retrieved 19 July 2009.
226. ^ "Welcome to the Galileo Orbiter Archive Page". PDS Atmospheres Node. 18 October 1989. Archived from the original on 11 April 2023. Retrieved 11 April 2023.
227. ^ Howell, Elizabeth (16 December 2014). "Venus Express Out Of Gas; Mission Concludes, Spacecraft On Death Watch". Universe Today. Archived from the original on 22 April 2021. Retrieved 22 April 2021.
228. ^ Hatfield, Miles (9 February 2022). "Parker Solar Probe Captures Visible Light Images of Venus' Surface". NASA. Archived from the original on 14 April 2022. Retrieved 29 April 2022.
229. PMID 35864851
     .
230. S2CID 256599851
     .
231. ^ Clark, Stuart (26 September 2003). "Acidic clouds of Venus could harbour life". New Scientist. Archived from the original on 16 May 2015. Retrieved 30 December 2015.
232. ^ Redfern, Martin (25 May 2004). "Venus clouds 'might harbour life'". BBC News. Archived from the original on 16 September 2020. Retrieved 30 December 2015.
233. doi:10.1016/j.icarus.2015.05.006
     .
234. S2CID 11784372. Archived
     from the original on 17 September 2020. Retrieved 17 September 2020.
235. ^ Anderson, Paul (3 September 2019). "Could microbes be affecting Venus' climate?". Earth & Sky. Archived from the original on 3 September 2019. Retrieved 3 September 2019.
236. S2CID 221655331
     .
237. ^ Perkins, Sid (14 September 2020). "Curious and unexplained". Science. Archived from the original on 14 September 2020. Retrieved 14 September 2020.
238. S2CID 221127006
     .
239. ^ Sample, Ian (14 September 2020). "Scientists find gas linked to life in atmosphere of Venus". The Guardian. Archived from the original on 5 February 2021. Retrieved 16 September 2020.
240. ^ Kooser, Amanda (14 September 2020). "NASA chief calls for prioritizing Venus after surprise find hints at alien life". CNet. Archived from the original on 15 September 2020. Retrieved 14 September 2020.
241. ^ @JimBridenstine (14 September 2020). "Life on Venus?" (Tweet) – via Twitter.
242. ^ Plait, Phil (26 October 2020). "Update: Life Above Hell? Serious doubt cast on Venus phosphine finding". Syfy.com. Syfy. Archived from the original on 29 October 2020. Retrieved 26 October 2020.
243. S2CID 224803085
     .
244. doi:10.1093/mnrasl/slaa187
     .
245. S2CID 236090264
     .
246. ^ "Rocket Lab Probe". Venus Cloud Life – MIT. 7 March 2023. Archived from the original on 8 February 2024. Retrieved 13 May 2023.
247. ISBN 978-0-309-10150-9. Archived
     from the original on 17 July 2015. Retrieved 19 January 2021.
248. ^ Frazier, Sarah (19 February 2021). "Parker Solar Probe Primed for Fourth Venus Flyby". NASA. Archived from the original on 22 April 2021. Retrieved 22 April 2021.
249. ^ Kolirin, Lianne (18 September 2020). "Venus is a Russian planet—say the Russians". CNN. Archived from the original on 20 September 2020. Retrieved 21 September 2020.
250. ^ Leman, Jennifer (18 September 2020). "Venus Is a Russian Planet ... Says Russia". Popular Mechanics. Archived from the original on 20 September 2020. Retrieved 21 September 2020.
251. ^ Rao, Rahul (7 July 2020). "Astronauts bound for Mars should swing by Venus first, scientists say". Space.com. Archived from the original on 24 April 2023. Retrieved 24 April 2023.
252. S2CID 219558707
     .
253. ^ "Архив фантастики". Архив фантастики (in Russian). Archived from the original on 2 September 2021. Retrieved 2 September 2021.
254. ISBN 978-3-319-19568-1
     .
255. ^
     doi:10.1063/1.1541418. Archived from the original
     on 11 July 2012.
256. ^ Tickle, Glen (5 March 2015). "A Look Into Whether Humans Should Try to Colonize Venus Instead of Mars". Laughing Squid. Archived from the original on 1 September 2021. Retrieved 1 September 2021.
257. ^ Warmflash, David (14 March 2017). "Colonization of the Venusian Clouds: Is 'Surfacism' Clouding Our Judgement?". Vision Learning. Archived from the original on 11 December 2019. Retrieved 20 September 2019.
258. doi:10.1111/j.1467-8365.1986.tb00206.x
     .
259. ^ Boime, Albert (December 1984). "Van Gogh's Starry Night: A History of Matter and a Matter of History" (PDF). Arts Magazine: 88. Archived (PDF) from the original on 23 November 2018. Retrieved 28 July 2018.
260. ^ "Aphrodite and the Gods of Love: Roman Venus (Getty Villa Exhibitions)". Getty. Archived from the original on 12 April 2023. Retrieved 15 April 2023.
261. ^
     ISBN 978-0-313-29497-6
     . Retrieved 2 February 2023.
262. ^
     ISBN 978-0-7141-1705-8. Archived
     from the original on 20 November 2020. Retrieved 23 August 2020.
263. ISSN 1971-8608. Archived
     from the original on 24 December 2019. Retrieved 28 December 2017.
264. ^
     S2CID 120565237
     .
265. ^
     ISBN 978-0-19-064792-6
     .
266. ISBN 978-0-521-49652-0
     .
267. ^ ^{a b} "Lucifer". Encyclopædia Britannica Online. 24 January 2020. Archived from the original on 24 January 2020. Retrieved 3 February 2023.
268. ^ Cicero, Marcus Tullius (12 September 2005). De Natura Deorum. Archived from the original on 12 September 2005. Retrieved 3 February 2023..
269. ^ Atsma, Aaron J. "Eospheros & Hespheros". Theoi.com. Archived from the original on 14 July 2019. Retrieved 15 January 2016.
270. ISBN 978-0-14-200116-5
     .
271. ISBN 978-81-223-0902-7
     .
272. ISBN 978-0-940985-51-3
     .
273. ^ De Groot, Jan Jakob Maria (1912). Religion in China: universism. a key to the study of Taoism and Confucianism. American lectures on the history of religions. Vol. 10. G. P. Putnam's Sons. p. 300. Archived from the original on 22 July 2011. Retrieved 8 January 2010.
274. ISBN 978-0-415-05609-0
     .
275. ^ Hulbert, Homer Bezaleel (1909). The passing of Korea. Doubleday, Page & company. p. 426. Retrieved 8 January 2010.
276. ^ "Sao Kim – VOER". Vietnam Open Educational Resources. Archived from the original on 26 December 2022. Retrieved 26 December 2022.
277. ISBN 978-0-89412-244-6
     .
278. ISBN 978-0-292-79793-2
     .
279. ISBN 978-0-7613-2359-4
     .
280. ISBN 978-0-521-79912-6
     .
281. ISBN 978-1-4051-1218-5
     . Retrieved 3 February 2023.
282. PMID 16373733
     .
283. ^ ^{a b c} Stearn, William T. (17 August 1961). "The Male and Female Symbols of Biology". New Scientist (248): 412–413. Archived from the original on 23 November 2021.
284. ^
     S2CID 87030547
     .
285. ^ Brammer, John Paul (10 February 2020). "Love/Hate Reads: 'Men Are From Mars, Women Are From Venus,' Revisited". VICE. Archived from the original on 17 April 2023. Retrieved 17 April 2023.
286. ^ Morin, Amy (19 August 2016). "Why The Mars And Venus Conversations Must End: The Truth About Gender Differences In The Workplace". Forbes. Archived from the original on 17 April 2023. Retrieved 17 April 2023.

External links

Wikisource has several original texts related to Venus.

• Venus profile at NASA's Solar System Exploration site
• Missions to Venus and Image catalogue at the
  National Space Science Data Center
• Soviet Exploration of Venus and Image catalogue at Mentallandscape.com
• Image catalogue from the Venera missions
• Venus page at The Nine Planets
• Transits of Venus at NASA.gov
• Geody Venus, a search engine for surface features
• Interactive 3D gravity simulation of the pentagram that the orbit of Venus traces when Earth is held fixed at the centre of the coordinate system

Cartographic resources

• Map-a-Planet: Venus by the
  U.S. Geological Survey
• Gazetteer of Planetary Nomenclature: Venus by the International Astronomical Union
• Venus crater database by the Lunar and Planetary Institute
• Map of Venus by Eötvös Loránd University
• Google Venus 3D, interactive map of the planet

Retrieved from "https://en.wikipedia.org/w/index.php?title=Venus&oldid=1226361837"