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|language=Slovak}}</ref> This planet is tilted on its side in such a way, that its axis lies nearly in level with its path around the sun.<ref>{{cite web |title=Facts About Uranus  |url=http://lifestyle.iloveindia.com/lounge/facts-about-uranus-3487.html |accessdate=July 12, 2015}}</ref><ref>{{cite web |title= Solar System Exploration: Uranus and Moons |url=http://solarsystem.nasa.gov//multimedia/display.cfm?IM_ID=422 |publiihser=NASA |accessdate=July 12, 2015}}</ref> Uranus spins clockwise, or in a retrograde fashion, about its north pole, which is opposite to the prograde spin of Earth and most of the other planets.<ref>{{cite web |title= Uranus |publisher=www.enacademic.com |url=http://universalium.academic.ru/226966/Uranus#sel=  |accessdate=July 12, 2015 |quote= Uranus The planet is estimated to rotate about every 17 hours around an unusual axis that is almost parallel to the ecliptic; from Earth it appears to spin on its side.  Because Uranus's spin axis is not perfectly parallel to the ecliptic, one of its poles is directed above the eclipticand the other below it. (The terms above and below refer to the same sides of the ecliptic as Earth's North and South poles, respectively.) According to international convention, the north pole of a planet is defined as the pole that is above the ecliptic regardless of the direction in which the planet is spinning. In terms of this definition,Uranus spins clockwise, or in a retrograde fashion, about its north pole, which is opposite to the prograde spin of Earth and most of the other planets.  

|language=Slovak}}</ref> This planet is tilted on its side in such a way, that its axis lies nearly in level with its path around the sun.<ref>{{cite web |title=Facts About Uranus  |url=http://lifestyle.iloveindia.com/lounge/facts-about-uranus-3487.html |accessdate=July 12, 2015}}</ref><ref>{{cite web |title= Solar System Exploration: Uranus and Moons |url=http://solarsystem.nasa.gov//multimedia/display.cfm?IM_ID=422 |publiihser=NASA |accessdate=July 12, 2015}}</ref> Uranus spins clockwise, or in a retrograde fashion, about its north pole, which is opposite to the prograde spin of Earth and most of the other planets.<ref>{{cite web |title= Uranus |publisher=www.enacademic.com |url=http://universalium.academic.ru/226966/Uranus#sel=  |accessdate=July 12, 2015 |quote= Uranus The planet is estimated to rotate about every 17 hours around an unusual axis that is almost parallel to the ecliptic; from Earth it appears to spin on its side.  Because Uranus's spin axis is not perfectly parallel to the ecliptic, one of its poles is directed above the eclipticand the other below it. (The terms above and below refer to the same sides of the ecliptic as Earth's North and South poles, respectively.) According to international convention, the north pole of a planet is defined as the pole that is above the ecliptic regardless of the direction in which the planet is spinning. In terms of this definition,Uranus spins clockwise, or in a retrograde fashion, about its north pole, which is opposite to the prograde spin of Earth and most of the other planets.  

When Voyager 2 flew by Uranus in 1986, the north pole was in darkness, and the Sun was almost directly overhead at the south pole. In 42 years, or one-half the Uranian year, the Sun will havemoved to a position nearly overhead at the north pole. The prevailing theory is that the severe tilt arose during thefinal stages of planetary accretion when bodies comparable in size to the present planets collided in a series of violent events that knocked Uranus on its side. An alternate theory is that a Mars-sized moon, orbiting Uranus in a direction opposite to the planet's spin, eventually crashed into the planet and knocked it on its side.

When Voyager 2 flew by Uranus in 1986, the north pole was in darkness, and the Sun was almost directly overhead at the south pole. In 42 years, or one-half the Uranian year, the Sun will havemoved to a position nearly overhead at the north pole. The prevailing theory is that the severe tilt arose during thefinal stages of planetary accretion when bodies comparable in size to the present planets collided in a series of violent events that knocked Uranus on its side. An alternate theory is that a Mars-sized moon, orbiting Uranus in a direction opposite to the planet's spin, eventually crashed into the planet and knocked it on its side.

   Uranus's rotation period of 17.24 hours was inferred when Voyager 2 detected radio wave emissions with thatperiod coming from charged particles trapped in the planet's magnetic field. Subsequent direct measurements ofthe field showed that it is tilted at an angle of 58.6° relative to the rotation axis and that it turns with the same 17.24-hour period.}}</ref> This makes assumptions on the common direction of rotational motion of all planets coming from parental spinning disk hardly maintainable. Hypothesis was also criticised by British physicist [[James Clerk Maxwell]] <ref name="Maxwell">{{cite web |title=James Clerk Maxwell Revolutionary Contributions to Electromagnetism and the Kinetic Theory of Gases |publisher=Electro.Patent-Invent.com |url=http://www.patent-invent.com/electricity/inventors/james_maxwell.html |accessdate=12 July 2015 |quote=Astrophysics of Gaseous Nebulae: Maxwell published in 1859 his outstanding essay, On the Stability of Saturn's Rings, in which he concluded that Saturn rings could not be completely solid or fluid. Maxwell showed that the rings' stability could be achieved only on the condition that the rings consisted a large number of small solid particles. In this essay he also disproved mathematically the nebular hypothesis of his time which stated that the solar system was formed through the condensation of a purely gaseous nebula without any solid particles present. For this, Maxwell was awarded the Adams prize the same year in Cambridge.}}</ref> and British mathematician and astrophysicist James Jeans.<ref name="CMIonNebula"/> Maxwell was awarded the Adams prize in Cambridge for his outstanding 1859 essay ''"On the Stability of Saturn's Rings"'', where he i.a. mathematically disproved the nebular hypothesis of his time which stated that the solar system was formed through the condensation of a purely gaseous nebula without any solid particles present.<ref name="Maxwell"/> Jeans calculated how massive a cloud must be so that gravity can overcome the tendency for gas to expand and found out that no star could have formed this way.<ref name="CMIonNebula"/>  

   Uranus's rotation period of 17.24 hours was inferred when Voyager 2 detected radio wave emissions with thatperiod coming from charged particles trapped in the planet's magnetic field. Subsequent direct measurements ofthe field showed that it is tilted at an angle of 58.6° relative to the rotation axis and that it turns with the same 17.24-hour period.}}</ref> This makes assumptions on the common direction of rotational motion of all planets coming from parental spinning disk hardly maintainable.{{#tag:ref|Previously [[Buffon]] has suggested that the curious fact that the by-then-known planets all move "from west to east" and their orbits all lie within the plane of the ecliptic should be interpreted as "confirmation" of his hypothesis that a comet inveted by him had detached pieces of the sun, sending these fragments into planetary orbits. His theory of the origin of the solar system was explicitly meant to replace Newton's view that God had imparted inertial motion to the planets.<ref name="Rappaport1997">{{cite book |title=When Geologists Where Historians, 1665-1750 |author=Rhoda Rappaport |publisher=Cornell University Press |place=Ithaca and London |year=1997 |pages=242 |isbn=978-0801-433863 |url=http://books.google.com/books?id=30U3W2kI7foC}}</ref>|group=note}} Hypothesis was also criticised by British physicist [[James Clerk Maxwell]] <ref name="Maxwell">{{cite web |title=James Clerk Maxwell Revolutionary Contributions to Electromagnetism and the Kinetic Theory of Gases |publisher=Electro.Patent-Invent.com |url=http://www.patent-invent.com/electricity/inventors/james_maxwell.html |accessdate=12 July 2015 |quote=Astrophysics of Gaseous Nebulae: Maxwell published in 1859 his outstanding essay, On the Stability of Saturn's Rings, in which he concluded that Saturn rings could not be completely solid or fluid. Maxwell showed that the rings' stability could be achieved only on the condition that the rings consisted a large number of small solid particles. In this essay he also disproved mathematically the nebular hypothesis of his time which stated that the solar system was formed through the condensation of a purely gaseous nebula without any solid particles present. For this, Maxwell was awarded the Adams prize the same year in Cambridge.}}</ref> and British mathematician and astrophysicist James Jeans.<ref name="CMIonNebula"/> Maxwell was awarded the Adams prize in Cambridge for his outstanding 1859 essay ''"On the Stability of Saturn's Rings"'', where he i.a. mathematically disproved the nebular hypothesis of his time which stated that the solar system was formed through the condensation of a purely gaseous nebula without any solid particles present.<ref name="Maxwell"/> Jeans calculated how massive a cloud must be so that gravity can overcome the tendency for gas to expand and found out that no star could have formed this way.<ref name="CMIonNebula"/>  

Furthermore, Kant-Laplace theory maintains that at the time of separation from ancestral solar nebula, our Earth was a hot molten gaseous sphere. This ball again, by virtue of centrifugal force, ejected a ring that rolled up into another sphere thus forming Earth’s Moon. By means of radiating energy into surrounding cold space, the Earth gradually cooled and contracted more and more thus turning into some kind of lava, and, at the end, thickened at the surface into solid crust covering hot Earth’s interior until the present day. On the cooling Earth’s surface, hot vapors and gases condensed into water, and atmosphere also originated as by product of this process.   

Furthermore, Kant-Laplace theory maintains that at the time of separation from ancestral solar nebula, our Earth was a hot molten gaseous sphere. This ball again, by virtue of centrifugal force, ejected a ring that rolled up into another sphere thus forming Earth’s Moon. By means of radiating energy into surrounding cold space, the Earth gradually cooled and contracted more and more thus turning into some kind of lava, and, at the end, thickened at the surface into solid crust covering hot Earth’s interior until the present day. On the cooling Earth’s surface, hot vapors and gases condensed into water, and atmosphere also originated as by product of this process.   

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==References==