Which planet is moving on its side? Scientists have explained why Uranus rotates “lying on its side. Why is it colder on the sunny side?

This name is incredible interesting planet received in honor of the father of the Roman god Saturn. It was Uranus that became the first planet to be discovered in modern history. However, at first this planet was classified as a comet in 1781, and only later observations by astronomers proved that Uranus is a real planet. Our review contains interesting and interesting facts about the seventh planet from the Sun, where summer lasts 42 years.

1. Seventh Planet

Uranus is the seventh planet in distance from the Sun, which ranks third in size and fourth in mass in the Solar System. It is not visible to the naked eye, which is why Uranus was the first planet discovered using a telescope.

2. Uranus was discovered in 1781

Uranus was officially discovered by Sir William Herschel in 1781. The name of the planet comes from the ancient Greek deity Uranus, whose sons were giants and titans.

3. Too, too faded...

Uranus is too faint to be seen without special equipment. At first, Herschel thought it was a comet, but a few years later it was confirmed that it was still a planet.

4. The planet lies “on its side”

The planet rotates in reverse direction, opposite to Earth and most other planets. Since the axis of rotation of Uranus is located unusually (the planet lies “on its side” relative to the plane of rotation around the Sun), one of the planet’s poles is in complete darkness for almost a quarter of the year.

5. The smallest of the “giants”

Uranus is the smallest of the four "giants" (which also include Jupiter, Saturn and Neptune), but it is several times larger than Earth. Uranus has an equatorial diameter of 47,150 km, compared to Earth's diameter of 12,760 km.

6. Atmosphere of hydrogen and helium

Like other gas giants, Uranus' atmosphere is composed of hydrogen and helium. Below that is an icy mantle that surrounds a core of rock and ice (which is why Uranus is often called the “ice giant”). The clouds on Uranus are composed of water, ammonia and methane crystals, which give the planet its pale blue color.

7. Uranus helped with Neptune

Since Uranus was first discovered, scientists have noticed that at certain points in its orbit the planet veers further into space. In the nineteenth century, some astronomers suggested that this attraction was due to the gravity of another planet. By making mathematical calculations based on observations of Uranus, two astronomers, Adams and Le Verrier, determined the location of the other planet. It turned out to be Neptune, located at a distance of 10.9 astronomical units from Uranus.

8. 19.2 astronomical units

Distances in the Solar System are measured in astronomical units (AU). The distance of the Earth from the Sun was taken as one astronomical unit. Uranus is located at a distance of 19.2 AU. from the sun.

9. Internal heat of the planet

One more amazing fact about Uranus is that the internal heat of the planet is less than that of other giant planets in the solar system. The reason for this is unknown.

10. Eternal haze of methane

The upper atmosphere of Uranus is a perpetual haze of methane. She hides the storms that rage in the clouds.

11. Two external and eleven internal

Uranus has two sets of very thin, dark-colored rings. The particles that make up the rings are very small: from the size of a grain of sand to small pebbles. There are eleven inner rings and two outer rings, the first of which were discovered in 1977 when Uranus passed in front of the star and astronomers were able to observe the planet using the Hubble Telescope.

12. Titania, Oberon, Miranda, Ariel

Uranus has a total of twenty-seven moons, most of which were named after characters in Shakespeare's A Midsummer Night's Dream. The five main moons are called Titania, Oberon, Miranda, Ariel and Umbriel.

13. Ice canyons and terraces of Miranda

The most interesting satellite of Uranus is Miranda. It has ice canyons, terraces and other strange looking surface areas.

14. Lowest temperature in the solar system

Uranus recorded the lowest temperature on the planets in the solar system - minus 224 ° C. Although such temperatures were not observed on Neptune, this planet is colder on average.

15. Period of revolution around the Sun

A year on Uranus (i.e., the period of revolution around the Sun) lasts 84 Earth years. For about 42 years, each of its poles is in direct sunlight, and the rest of the time it is in complete darkness.

For everyone who is interested in the extraterrestrial topic, we have collected.

The celestial bodies located in our galaxy after Saturn have been little studied - space research probes have practically never visited these places. However, some earthlings about this area solar system learned. For example, we know which planet rotates while lying on its side.

The tilt of the rotation axis of Uranus

Every body planetary type in the Solar System has its own inclination of the rotational axis, which is the angle between the plane of its equator and the ecliptic - the plane in which the body moves around the star.

But Uranus has a record value - almost 98°. It turns out that this body rotates in a “lying on its side” position, as if rolling along its orbital trajectory.

This phenomenon caused a special change in the Uranian seasons of the year and time of day.

At the time of winter or summer solstice:

• one of the planetary poles “looks” at the Sun;
• in this hemisphere the polar day lasts, in the opposite hemisphere there is a polar night;
• in the equatorial region, day and night quickly alternate;
• an observer at the equator sees the star located extremely low above the horizon, approximately the same as in the polar latitudes on our planet;
• standing at the pole, you can see how the Sun rises almost to the zenith along a spiral trajectory over the course of 21 years, and then spirals down below the horizon for the same number of years.

After local 6 months, during which 42 years will pass on Earth, Uranus will turn to the central luminary of the system with the opposite pole, the situation will be reversed.

The planet also has spring and autumn equinoxes. At these moments, the Sun is almost above the equator, and the result is the cycle of day and night familiar to other planets.

The next equinox - autumn in the southern hemisphere and spring in the northern - began here in 2007 and will last until 2028, when it will be replaced by the winter and summer equinoxes, respectively.

There is some disagreement among scientists about which hemisphere of Uranus is considered northern and which is southern. The unusual position of the celestial body does not allow the poles to be accurately identified. As a result of discussions, it was decided to define them in the same way as on other planets - in relation to the north and south poles of the world.

What caused the tilt of Uranus

There are at least 2 versions of why Uranus lies on its side. Some scientists believe that the planet once had a fairly large natural moon that influenced the Uranian axis of rotation.

Subsequently, the moon collapsed or changed its orbit, but the position of the axis did not change. Opponents of the theory object that today the planet's satellites are tilted along with it. It is difficult to imagine an impact that would tilt both Uranus itself and its satellites.

There is an alternative hypothesis: at the very beginning of the formation solar planets Uranus collided with a large celestial body (presumably a young rock-ice protoplanet), which caused such an axial tilt. Such a collision could have happened 2-4 billion years ago.

Some astronomers are confident that the impact came out “grazingly” and not “head-on”, otherwise Uranus would have suffered much more destruction or would have completely ceased to exist in its modern form. Others argue that there were multiple collisions because a single impact would have caused other consequences, such as starting to spin in the other direction, but not such a flip.

Although this theory also does not explain why its moons rotated along with the planet, it was confirmed by the results of an experiment conducted by a group of astronomers from the United States and Great Britain. Researcher J. Kegerray and his assistants simulated the collision of a “correctly” rotating Uranus and a large object moving towards it (its dimensions should have been 2 times larger than those of Earth).

This fact not only led to a change in the position of the rotational axis, but also influenced the structure of the planet. The impact caused a significant loss of its thermal energy - it simply burst out of the Uranian depths and dissolved in space.

A second option is also possible: the debris of the collapsing oncoming object fell onto the planet in the form of a thin shell of rock around an ice layer, which isolated the internal planetary heat and caused the object to freeze. This explains why Uranus is now the coldest planetary body in the solar system.

Uranus is the seventh planet in order from the Sun in the Solar System. It is almost four times the diameter of the Earth. It is very far from the Sun and is relatively poorly lit. Uranus was discovered by the English scientist W. Herschel in 1781. Any details on the surface of Uranus cannot be distinguished due to the small angular dimensions of the planet in the field of view of the telescope. This complicates its research, including the study of rotation patterns. Apparently, Uranus (unlike all other planets) rotates around its axis as if lying on its side. This tilt of the equator creates unusual lighting conditions: at the poles in a certain season Sun rays fall almost vertically, and the polar day and polar night cover (alternately) the entire surface of the planet, except for a narrow strip along the equator. Since Uranus orbits the Sun every 84 years, the polar day at the poles lasts 42 years, then gives way to a polar night of the same duration. Only in the equatorial belt of Uranus the Sun regularly rises and sets with the periodicity of the planet’s uniform axial rotation.

Even in those areas where the Sun is at its zenith, the temperature on Uranus (more precisely on the visible surface of the clouds) is about -215 5o C. Under such conditions, some gases freeze. According to spectroscopic observations, hydrogen and a small admixture of methane were found in the composition of the atmosphere of Uranus. There is, according to indirect evidence, helium in relatively large quantities. Like other giant planets, Uranus has this composition, probably almost all the way to the center. However, the average density of Uranus (1.58 g/cm 53 0) is slightly greater than the density of Saturn and Jupiter, although the matter in the depths of these giants is much more compressed than on Uranus. This density of Uranus can be explained by the assumption of an increased helium content or the existence of a core of heavy elements in the depths of Uranus.

Planetologists spoke about the probable reason for the unusual position of Uranus. According to experts, in the past, Uranus collided with a protoplanetary body larger than Earth. Scientists presented research data in the Astrophysical Journal.

The magnetic poles of Uranus, according to astrophysicists, are shifted relative to the geographic ones by 60 degrees. Every Earth day they change places, and the planet’s rotation axis lies in the orbital plane. Specialists from the University of Durham (UK) have developed a computer model of the solar system in the era of its inception. Scientists tried to find out what processes influenced the location of Uranus' axis.

Scientists have suggested that Uranus collided with a large celestial body. As a result, the gas giant “lay down” on its side, and the other space object dissolved in its atmosphere. This process was accompanied by the ejection of large fragments of crust. They subsequently became the basis of the rings of the planet and its satellites.

According to the assumptions of planetary scientists, the asymmetry point in the bowels of Uranus was created by the remains of a celestial body. This affected the location of the magnetic field.

Each of the 8 planets in our solar system has its own unique characteristics. Some have a dense atmosphere of carbon dioxide or extensive rings, while others orbit the Sun “lying on its side.” We will talk about Uranus and its unusual position, which haunts scientists.

Uranus is the 7th planet in the solar system and belongs to the giant planets. Its average radius is 25,362 kilometers. It is believed that the planet consists mainly of ice: methane, water and ammonia. Hydrogen and helium are present in small quantities, and the planet’s atmosphere consists of them. Uranus has a ring system that is not as pronounced as Saturn's, but is still observable. On this moment 27 satellites of the planet were discovered.

Uranus makes one revolution around our star in 84 Earth years, and the period of rotation of the planet around its axis is 17 hours 14 minutes. But the position of this axis of rotation is very unusual. The plane of the planet's equator is inclined to the orbital plane at an angle of 97.86º, that is, it turns out that the planet rotates as if lying on its side and seems to be rolling in its orbit around the Sun.

This unusual location has led to the fact that the change of seasons on Uranus proceeds in a completely special way. At the moment of the solstice, one of the poles of Uranus faces the Sun, and at the equator there is a rapid change of day and night. After six months (that is, after 42 Earth years), the other pole turns towards the Sun. Despite the fact that the polar regions face the Sun for half a year, and the Sun shines very low at the equator, it turned out that the temperature at the equator is higher than at the poles during the “polar day”. Astronomers have not yet been able to figure out what is causing this temperature anomaly.

In addition, scientists have long pondered how it happened that Uranus has such a strange position. There are several versions of how this could have happened. Perhaps Uranus once had a fairly large satellite, under the influence of which its rotation axis underwent such changes. The satellite was lost over time, but the position of the axis remained unchanged. According to another version, at the dawn of the formation of the Solar system, a large celestial body collided with Uranus, which led to the tilt of the rotation axis.

A group of Anglo-American scientists led by astronomer Jacob Kegerray adheres to the same version. They simulated the collision of Uranus with a large object and presented the results of their experiment. Scientists believe that the collision could have occurred about 2-3 billion years ago, at the time of the formation of the planet, when it did not yet have satellites. According to astronomers, the size of the celestial body that collided with Uranus was 2 times greater than the size of our Earth. The impact could lead to a change in the position of the axis, and also affected the structure of the planet itself. As a result of the collision, Uranus lost part of the thermal energy contained in the bowels of the planet, and this can explain the fact that today Uranus is the coldest planet in our solar system. The temperature on its surface drops to minus 224ºС.