Venus

planet second-closest to the Sun in the Solar System
For the Roman goddess, see Venus (mythology).

Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. It is named after the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows. Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°.

Venus orbits the Sun at an average distance of about 108 million kilometres (about 0.7 AU) and completes an orbit every 224.65 days. Venus is the second planet from the Sun and it revolves round the Sun approximately 1.6 times (yellow trail) in Earth's 365 days (blue trail)


CONTENT : A - F , G - L , M - R , S - Z , See also , External links

Quotes edit

Quotes are arranged alphabetically by author

A - F edit

 
Fair Venus shines
Even in the eye of day ; with sweetest beam
Propitious shines, and shakes a trembling flood
Of softened radiance with her dewy locks.
The shadows spread apace; while meekened Eve,
Her cheek yet warm with blushes, slow retires
Through the Hesperian gardens of the west,
And shuts the gates of day. - Anna Letitia Barbauld.
 
The universe is globe-shaped, either because that is the most perfect shape of all, needing no joint, an integral whole; or because that is the most capacious of shapes, which is most fitting because it is to contain and preserve all...The first and highest of all is the sphere of the fixed stars, which contains itself and all things, and is therefore motionless. It is the location of the universe, to which the motion and position of all the remaining stars is referred.... - Nicolaus Copernicus.
 
Nicolaus Copernicus.
  • The universe is globe-shaped, either because that is the most perfect shape of all, needing no joint, an integral whole; or because that is the most capacious of shapes, which is most fitting because it is to contain and preserve all...The first and highest of all is the sphere of the fixed stars, which contains itself and all things, and is therefore motionless. It is the location of the universe, to which the motion and position of all the remaining stars is referred. For though some consider that it also changes in some respect, we shall assign another cause for its appearing to do so in our deduction of the Earth's motion. There follows Saturn, the first of the wandering stars, which completes its circuit in thirty years. After it comes Jupiter which moves in a twelve-year long revolution. Next is Mars, which goes round biennially. An annual revolution holds the fourth place, in which as we have said is contained the Earth along with the lunar sphere which is like an epicycle. In fifth place Venus returns every nine months. Lastly, Mercury holds the sixth place, making a circuit in the space of eighty days. In the middle of all is the seat of the Sun. For who in this most beautiful of temples would put this lamp in any other or better place than the one from which it can illuminate everything at the same time? Aptly indeed is he named by some the lantern of the universe, by others the mind, by others the ruler. Trismegistus called him the visible God, Sophocles' Electra, the watcher over all things. Thus indeed the Sun as if seated on a royal throne governs his household of Stars as they circle around him. Earth also is by no means cheated of the Moon's attendance, but as Aristotle says in his book On Animals the Moon has the closest affinity with the Earth. Meanwhile the Earth conceives from the Sun, and is made pregnant with annual offspring. We find, then, in this arrangement the marvellous symmetry of the universe, and a sure linking together in harmony of the motion and size of the spheres, such as could be perceived in no other way. For here one may understand, by attentive observation, why Jupiter appears to have a larger progression and retrogression than Saturn, and smaller than Mars, and again why Venus has larger ones than Mercury; why such a doubling back appears more frequently in Saturn than in Jupiter, and still more rarely in Mars and Venus than in Mercury; and furthermore why Saturn, Jupiter and Mars are nearer to the Earth when in opposition than in the region of their occultation by the Sun and re-appearance. Indeed Mars in particular at the time when it is visible throughout the night seems to equal Jupiter in size, though marked out by its reddish colour; yet it is scarcely distinguishable among stars of the second magnitude, though recognized by those who track it with careful attention.
  • We find then in this arrangement an admirable harmony of the world, and a dependable, harmonious interconnexion of the motion and the size of the paths, such as otherwise cannot be discovered. For here the penetrating observer can note why the forward and the retrograde movement of Jupiter appears greater than that of Saturn, and smaller than that of Mars, and again greater with Venus than with Mercury; and why such retrogression appears oftener with Saturn than with Jupiter, less often with Mars and Venus than with Mercury. Moreover, why Saturn, Jupiter, and Mars, when they rise in the evening, appear greater than when they disappear and reappear [with the sun]...And all this results from the same cause, namely the motion of the earth.
 
...The eight (formerly nine) recognized planets that orbit the Sun are, in order of increasing distance, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The first four are called terrestrial planets and the next four giant, or Jovian, planets. - Merriam Webster Dictionary.

G - L edit

 
The orbit of the earth is a circle; round the spheres to which this circle belongs describe a dodecahedron; the spheres including this will give the orbit of Mars. Round Mars describe a tetrahedron; the circle including this will be orbit of Jupiter. Describe a cube round Jupiter’s orbit; the circle including this will be Saturn. Now, inscribe in the earth’s orbit, an icosahedron, the circle inscribed in it will be the orbit of Venus: inscribe an octahedron in the orbit of Venus: the circle inscribed in it will be Mercury’s orbit. This is the reason of number of planets.- Kepler.
  • But what exceeds all wonders, I have discovered four new planets and observed their proper and particular motions, different among themselves and from the motions of all the other stars; and these new planets move about another very large star [Jupiter] like Venus and Mercury, and perchance the other known planets, move about the Sun. As soon as this tract, which I shall send to all the philosophers and mathematicians as an announcement, is finished, I shall send a copy to the Most Serene Grand Duke, together with an excellent spyglass, so that he can verify all these truths.
  • I therefore concluded, and decided unhesitatingly, that there are three stars in the heavens moving about Jupiter, as Venus and Mercury about the Sun; which at length was established as clear as daylight by numerous other observations. These observations also established that there are not only three, but four, erratic sidereal bodies performing their revolutions round Jupiter.
  • A similar situation occurred in astronomy, where the Newtonian law of gravitation had been found to predict the orbits of the outer planets with great accuracy, but had failed with the orbits of Mercury and Venus. The relativity theory of gravitation had provided the necessary modification of Newton's law, and in working out the details of the new theory, Einstein had utilized the fact that Newtonian law gave the right result at great distances from the sun. Heisenberg, confronted with a similar problem, was able to avail himself of the fact that the classical mechanics gave the right result at great distances from the atomic nucleus. Here, and here alone Heisenberg's theory made contact with the world of the older physics.
  • The orbit of the earth is a circle; round the spheres to which this circle belongs describe a dodecahedron; the spheres including this will give the orbit of Mars. Round Mars describe a tetrahedron; the circle including this will be orbit of Jupiter. Describe a cube round Jupiter’s orbit; the circle including this will be Saturn. Now, inscribe in the earth’s orbit, an icosahedron, the circle inscribed in it will be the orbit of Venus: inscribe an octahedron in the orbit of Venus: the circle inscribed in it will be Mercury’s orbit. This is the reason of number of planets.

M - R edit

 
...Neither Venus nor Mars has such a magnetic field, although the two planets are similar to Earth in many other ways.
Venus, unlike the earth has a hellish temperature. Venus is farther from the Sun than Mercury but is even hotter. The high temperature is due to an extreme greenhouse effect, the process by which the atmospheric gases raise the temperature by absorbing outward flowing heat. Earth’s atmosphere may once have contained large amounts of carbon dioxide, the way Venus’s atmosphere does now. But on earth, the oceans absorbed much of carbon dioxide, so that gas could not trap as much heat in the atmosphere as it does on Venus...
  • Mercury is a small world of extreme temperatures, with a global magnetic field like Earth’s, but much weaker. Neither Venus nor Mars has such a magnetic field, although the two planets are similar to Earth in many other ways.
    Venus, unlike the earth has a hellish temperature. Venus is farther from the Sun than Mercury but is even hotter. The high temperature is due to an extreme greenhouse effect, the process by which the atmospheric gases raise the temperature by absorbing outward flowing heat. Earth’s atmosphere may once have contained large amounts of carbon dioxide, the way Venus’s atmosphere does now. But on earth, the oceans absorbed much of carbon dioxide, so that gas could not trap as much heat in the atmosphere as it does on Venus.
    The three large terrestrial planets are like the bowls of cereals in the child’s story of Goldilocks. Venus is too hot, Mars is too cold, but Earth is just right to support liquid water and life as we know it…
    Venus is earth’s “evil twin”. It’s about the same size as earth, but with deadly heat and pressure, an unbreathable atmosphere, and highly acid rain
 
Figure of the heavenly bodies — An illustration of the Ptolemaic geocentric system - The Greek philosopher, Plato, in the fourth century B.C. asked his students if they could devise a theory or explanation to explain this erratic planetary motion using some form of circular motion. Being keen observers, the Greeks came up with the most logical and obvious conclusions; namely, that the earth was the center about which the sun, the moon, planets, and the stars rotated. This model of the universe is called a geocentric or earth-centered model.... -O.P.Puri
  • The Greek philosopher, Plato, in the fourth century B.C. asked his students if they could devise a theory or explanation to explain this erratic planetary motion using some form of circular motion. Being keen observers, the Greeks came up with the most logical and obvious conclusions; namely, that the earth was the center about which the sun, the moon, planets, and the stars rotated. This model of the universe is called a geocentric or earth-centered model. It satisfactorily explained the daily motion of the stars and sun by assuming that they were attached to invisible crystalline spheres that rotated about the earth. The axis of the sphere of the sun was tilted with respect to that of the stars to account for the variation of the sun's height at zenith with the various seasons. Since the sun appears to move through the stars and was brighter, it was assumed to be nearer to the earth than the stars. The spheres of the Moon, Mercury, and Venus were placed within the sphere of the sun while those of Mars, Jupiter, and Saturn were placed outside the sphere of the sun but within the sphere of the stars.
    • Quoted by O.P.Puri in: "Concepts in Physical Science", p. 7.
  • Why should Venus and Mercury have no satellites, and by what, when they exist, were they formed? The Astronomers 'do not know.' Because, we say, science has only one key — the key of matter — to open the mysteries of nature withal, while occult philosophy has seven keys and explains that which science fails to see. Mercury and Venus have no satellites, but they had 'parents' just as the Earth had. Both are far older than the Earth, and, before the latter reaches her seventh Round, her mother Moon will have dissolved into thin air, as the 'Moons' of the other planets have, or have not, as the case may be, since there are planets which have several moons — a mystery again which no Oedipus of astronomy has solved...
    • Helena Roerich, Letters of Helena Roerich Volume II: 1935-1939, 16 November 1935

S - Z edit

 
Some scientists believe that until about 500 million years ago the Venus surface was almost entirely devoid of landforms. Streams and oceans of molten rock were relentlessly pouring out of the interior filling in and covering over any relief that had managed to form. - Carl Sagan, Ann Druyan.
 
...Draw the curtain back for Venus, ere my vision grows too weak:
It is strange the pearly planet should look red as fiery Mars,--
God will mercifully guide me on my way amongst the stars. - Sarah Williams
 
The Venus transit is not a spectacle the way a total solar eclipse is a spectacle. - Neil deGrasse Tyson.
  • Venus has about 90 times more air than Earth. It isn't mainly oxygen and nitrogen as here—it's carbon dioxide. But carbon dioxide doesn't absorb visible light either. What would the sky look like from the surface of Venus if Venus had no clouds? With so much atmosphere in the way, not only are violet and blue waves scattered, but all other colours as well - green, yellow, orange, red. The air is so thick, though, that hardly any blue light makes it to the ground; it’s scattered back to space by successive bounces higher up. Thus the light that does reach the ground should be strongly reddened – like an Earth sunset all over the sky. Further sulfur in the high clouds will strain the sky yellow. Pictures taken by the Soviet Venera landers confirm that the skies of Venus are a kind of yellow-orange.
  • Those who are skeptical about carbon dioxide greenhouse warming might profitably note the massive greenhouse effect on Venus. No one proposes that Venus's greenhouse effect derives from imprudent Venusians who burned too much coal, drove fuel-inefficient autos, and cut down their forests.
  • There are certain calculations I should like to make with you,
    To be sure that your deductions will be logical and true;
    And remember, 'Patience, Patience,' is the watchword of a sage,
    Not to-day nor yet to-morrow can complete a perfect age.
    I have sown, like Tycho Brahe, that a greater man may reap;
    But if none should do my reaping, 'twill disturb me in my sleep
    So be careful and be faithful, though, like me, you leave no name;
    See, my boy, that nothing turn you to the mere pursuit of fame.
    I must say Good-bye, my pupil, for I cannot longer speak;
    Draw the curtain back for Venus, ere my vision grows too weak:
    It is strange the pearly planet should look red as fiery Mars,--
    God will mercifully guide me on my way amongst the stars.
  • To be sure, we do not have no absolute proof that Mars is inhabited [...] Personally, I have my faith on the feeble planetary electrical disturbances which I discovered in the summer of 1899, and which according to my investigations, could not have originated from the Sun, the Moon, or Venus. Further study since has satisfied me they must have emanated from Mars.
  • During my experiments here [Colorodo Springs 1899] Mars was at a relatively small distance from us, and in that dry and rarified air, Venus appeared as large and bright that it might have been mistaken for one of those military signaling lights...I came to the conclusion that Mars was sufficient to exert a noticeable influence on a delicate receiver of the kind I was perfecting...my ear barely caught signals coming in regular succession which could not have been produced on earth, caused by any solar or lunar action or by the influence of Venus, and the possibility that they might have come from Mars flashed upon my mind.
    • Nikola Tesla recounting his experiences in 1899 with the electrical disturbances he had received in: "Electrical Signals of Primary Origin".
  • Deserts are not confined to earth. The atmospheric circulation patterns of other terrestrial planets with gaseous envelopes also depend on the rotation of those planets, the tilts of their axes, their distances from the Sun and the composition and density of their atmospheres. Except for the poles the entire surface of Mars is a desert. Venus may also support deserts.

Venus Revealed: A New Look Below the Clouds of Our Mysterious Twin Planet edit

 
For me Venus holds special fascination because of it many close connections to Earth, and the important role it has played in our changing ideas about the universe and our place in it...
 
... A knowledge of close coincidence between the cycles of Venus and human pregnancy may have contributed to the persistent, but nonexclusive of female characteristic to Venus. Western attributes The Venus de Milo and Botticelli's birth of Venus (popularly known as Venus on the Half Shell) are icons of this imagery in Western culture.
 
Nowhere in recorded history has an awareness of the short-and long-term Earth-sky polyrhythms been as advanced and integrated into cultural life as in the knowledge and beliefs of the ancient Mesoamericans, and in particular the classic Maya of Central America, who flourished between AD 300 and 900. Maya felt that we owed our existence to Venus who they called Kukulcan and their astronomer-priests repaid the debt with the blood of human sacrifice....
 
...The planet is completely shrouded in clouds that reflect nearly 80 percent of the Sun’s light back into space, making Venus the brightest of worlds.

Robert Hunter in Terrapin Station quoted in : David Harry Grinspoon Venus Revealed: A New Look Below the Clouds of Our Mysterious Twin Planet, Basic Books, 1998

  • For me Venus holds special fascination because of it many close connections to Earth, and the important role it has played in our changing ideas about the universe and our place in it. It is brightest thing in our night sky, after the full moon, and has long attracted human worship, fear, and calculation. A slightly twin to our planet in size and weight, Venus ( as we have learnt recently) is also currently active planet with a churning interior, young surface and continually recycling atmosphere. It is in many ways the most Earth like of other planets and a natural laboratory for studying some of the most crucial environmental tests facing us.
    • In:p.xiii.
  • As Venus moves up and down through our twilight skies, the farthest it gets from the Sun is an angle of about 47 degrees. (This is "maximum elongation")
    • In:p.9.
  • You can feel when you are locked in resonance in a circle of drummers playing parts complimentary to yours. Venus and Earth have been locked in this same way, beating five against eight, for billions of years. There is no accepted physical explanation for the Venus-Earth five/eight polyrhythm. Some regard it as merely a coincidence, noting that the correspondence is not exact (it is actually off by two days of 2,820). But I suspect that this close rhythmic connection between the orbits of Venus and Earth goes back to the time when the planets were being formed from collisions between smaller “planetesimals”.
    • On the noted aspect of music in planetary orbits in: p. 11.
  • Nowhere in recorded history has an awareness of the short-and long-term Earth-sky polyrhythms been as advanced and integrated into cultural life as in the knowledge and beliefs of the ancient Mesoamericans, and in particular the classic Maya of Central America, who flourished between AD 300 and 900. Maya felt that we owed our existence to Venus who they called Kukulcan and their astronomer-priests repaid the debt with the blood of human sacrifice. Unfortunately, almost everything we know about the Maya’s sophisticated and complex system of Venus observations/ computations/prediction/worship comes from only four books that escaped the book-burning frenzy of the invading Christians. Included in this meticulously painted bark paper books is an abundance of astronomical information, including table of solar and lunar motions and table of Venus ephemeris, or table of motions, which is accurate for over a hundred years. The entire Mayan calendar, as were those of all Mesoamerican civilizations, was based on the 260-days Venus appearance interval. The 260-day Mayan calendar is still in use today in many areas of Guatemala. The 260-day Venus interval and the 365-day year come into phase every 18,980 days, or 53 years.
    • In:p.19.
  • But first let's trace the origin and history of the popular vision of Venus as Earth's soggy twin. The striking brilliance that makes Venus such a noticeable presence in our sky results paradoxically from the same feature that long kept her cloaked in mystery. The planet is completely shrouded in clouds that reflect nearly 80 percent of the Sun’s light back into space, making Venus the brightest of worlds.
    • In:p.32.
  • Venus, all you need to do is identify some feature or mark and note the time it takes to reappear, as it rotates around the globe. Beginning in 1666, Cassini made the first attempt to do this. He found a rotation period of 23 hours and 21 minutes. In 1789, Schroder refined this estimate to 23 hours , 21 minutes, and 19 seconds.
    • In:p.45.
  • For Venus is (as was well known by early telescopic observers) literally right next door. The closest planet to Earth, at every inferior conjunction she swings to within one hundred times the Moon's distance.
    • In:p.50.
  • In 1956, passive radio observations had allowed a startling discovery that led to the first serious challenge to the fantasies of a warm, wet Venus. Mysteriously, the planet was emitting very large amounts of microwave radiation. Further observations in the 1960s confirmed its brightness when viewed with microwave eyes.
    • In:p.63.
  • As long as Venus remained an object of distant observation in our sky, there was no way to be sure, and science fiction writers were free to populate Venus with ocean-dwelling beasts and evil dictators (news of the problematical microwaves was first published the same year that Zsa Zsa was thrilling audiences with her Venusian antics). We had to go there to demand some answers. This is where the rockets enter the story... the cold-war “space race” was on, science was along for the ride, onward to the planets.
    • In:p.63.
 
On Earth, only dust and pebbles get snuffed (making "shooting stars"), but on Venus you don't get any craters smaller than about two miles across. We expected this. In fact, the small size cutoff of craters conforms so closely to pre-Magellan predictions that it was a confidence booster for our models of the passage of small bodies through planetary atmospheres.
 
Artist's depiction of Magellan at Venus. - We are just starting to think about how similar feed backs between the surface and atmosphere may be affecting the climate on Venus. Although the Magellan mission was mostly about the surface, it has caused us to rethink much of what we thought we knew about the atmosphere.
  • ...throughout the 60s, 70s, and 80s our understanding of Venus slowly increased in depth and sophistication. But still the clouds did not clear, and major mysteries remained. The early Soviet efforts produced a string of failures...[[w:Venera 3|Venera 3 –actually reached Venus only to crash into the planet on March 1, 1966... the first successful mission Venera 4, reached Venus in October 1967 ---first planetary probe to enter the atmosphere of another planet, do direct experiments and radio home the results...During its brief (ninety-four –minute) decent by parachute, the spacecraft measured conditions in and below the clouds, confirming that the atmosphere of Venus is mostly carbon dioxide and recording increasing temperatures and pressure... at an altitude of more than sixteen miles.
    • In:p.75.
  • On Earth, only dust and pebbles get snuffed (making "shooting stars"), but on Venus you don't get any craters smaller than about two miles across. We expected this. In fact, the small size cutoff of craters conforms so closely to pre-Magellan predictions that it was a confidence booster for our models of the passage of small bodies through planetary atmospheres.
    • In: p. 254.
  • But on Venus you can't tell, so the hypothesis is consistent with the way all the craters sit atop the "paint job" of planet wide lava flows. Unfortunately, this scenario is only slightly more plausible than crater-worshiping.
    • In: p. 258.
  • Venus should have a similar overall heat production, and it has to be losing this heat somehow. It can't be holding it inside because the whole planet would just be molten. It is not enough to simply pronounce that Venus looks different from Earth so it does not have plate tectonics. We have to find some cooling mechanism.
    • In: p. 264.
  • We are just starting to think about how similar feed backs between the surface and atmosphere may be affecting the climate on Venus. Although the Magellan mission was mostly about the surface, it has caused us to rethink much of what we thought we knew about the atmosphere.
    • In: p. 281.
  • Mars is the most Earthlike of the other planets in its surface conditions, but Venus may be the most Earthlike in its activity. All three planets started out young and restless, with warm, churning interiors and water flowing on their surfaces. But they have gone their separate ways. Mars cooled off...Venus, too, lost its ocean, but it retains an active churning interior and a surface that has been reworked many times by processes that are apparently still ongoing.
    • In: p. 314.

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