Like others giant planets, Uranus' atmosphere is mainly composed of hydrogen, helium and methane, although their relative contributions are slightly lower compared to Jupiter and Saturn.
The theoretical model of the structure of Uranus is as follows: its surface layer is a gas-liquid shell, under which there is an ice (a mixture of water and ammonia ice) a mantle, and even deeper - a core of hard rocks. Mantle and core mass is about 85-90% of the total mass of Uranus. The zone of solid matter extends to 3/4 of the planet's radius.
The temperature in the center of Uranus is close to 10,000 K at a pressure of 7-8 million atmospheres (one atmosphere roughly corresponds to one bar). At the core boundary, the pressure is about two orders of magnitude lower (about 100 kilobars).
Effective temperature, determined by thermal radiation from the planet's surface, is about 55 K.
Uranus formed from the original solids and various ice(here ice should be understood not only as water ice), it consists of only 15% hydrogen, and there is almost no helium at all (in contrast to Jupiter and Saturn, which, for the most part, are hydrogen). Methane, acetylene and other hydrocarbons exist in much larger quantities than on Jupiter and Saturn. Mid-latitude winds on Uranus move clouds in the same directions as on Earth. These winds blow at a speed of 40 to 160 meters per second; on Earth, fast streams in the atmosphere move at a speed of about 50 meters per second.
Thick layer (haze) - photochemical smog- is found around the sunlit pole. The hemisphere illuminated by the sun also emits more ultraviolet radiation. In the above image of Uranus, the color contrast is artificially enhanced to reveal the difference between the two.
Voyager's instruments found a somewhat colder strip between 15 and 40 degrees latitude, where temperatures are 2-3 K cooler.
Uranus' blue color is the result of the absorption of red light by methane in the upper atmosphere.... There are probably clouds of other colors, but they are hidden from observers by an overlying methane layer. The atmosphere of Uranus (but not Uranus as a whole!) Is about 83% hydrogen, 15% helium and 2% methane. Like others gas planets, Uranus has cloud bands that move very quickly. But they are too poorly distinguishable and are only visible in the high-resolution images taken by Voyager 2. Recent observations with HST have revealed large clouds. There is an assumption that this opportunity appeared in connection with seasonal effects, because it is not difficult to figure out that winter from summer on Uranus varies greatly: the whole hemisphere in winter hides from Suns! However, Uranus receives 370 times less heat from the Sun than the Earth, so there is no hot summer there either. In addition, Uranus emits no more heat than it receives from the Sun, therefore, most likely, it is cold inside.
The depletion of the planet's atmosphere in light gases is a consequence of the insufficient mass of the planet's embryo. In the course of formation, Uranus could not keep near itself a larger amount of hydrogen and helium only because by the time the future Uranus collected a sufficiently massive core, there was little free hydrogen and helium in the solar system. But Uranium contains more water, methane, acetylene.
The planet Uranus owes its discovery to Herschel, who studied the sky in a telescope he designed.
Prior to its discovery, the planet Uranus was repeatedly sighted and mistakenly assigned to the stars. Among the stationary celestial bodies, the English astronomer noticed one moving along a trajectory and differing from the others in color. So, in late XVIII century was discovered new planet... In the chosen name, the discoverer wanted to glorify King George III, but his idea was not successful. A few years later, the German Bonet, who continued to study the unknown body, proposed the name of the Greek god - Uranus, which was recognized by the public.
Location
Uranus managed to remain unnoticed for so long because of its exceptional remoteness from the luminary. The distance from the Sun to the distant giant is 2.8 billion km. This is the seventh planet in our system. Astronomers put it in the group of gas giants. The colossal distance from the source of heat and energy made Uranus the coldest planet among all studied. On the surface of the giant, record low temperatures have been recorded, it drops to -220 degrees Celsius.
Features of the planet
Uranus is unique in its location, with its axis tilted at 98 degrees, which causes the original planet to orbit while lying on its side. In this position, the main flow of solar energy is directed to the area of the poles, but, contrary to logical conclusions, the temperature at the equator has higher rates. The direction of rotation of the ice giant is opposite to that of its orbital motion. Uranus makes one revolution in 84 Earth years, and a day passes in 17 hours, this period is calculated approximately due to the uneven movement of the gaseous surface.
Features of the structure and atmosphere
The mass of the celestial body is 8.68x10 in 25 kg, it is less than the weight of the gas giants located nearby. This is due to the planet's minimum density of 1.27 g / cm3, which is based on light components. Its structure includes a core of iron and stone; mantle - an ice body that makes up most the giant, and the atmosphere. This model was developed theoretically, its basis was the study of the gravitational effect of Uranus on satellites. A spectacular blue glow to the planet is given by the presence of methane particles in the upper layers, its mass fraction is 2%. The basis of the gas envelope is hydrogen - 82% and helium - 15%. The remainder is divided into ammonia and acetylene. The mantle is not an ice shell in the physical sense - it is a modified mixture of water and ammonia. There is no solid surface on the planet, this level is calculated conventionally based on pressure indicators.
The lower atmosphere is dynamic and prone to hurricane winds. Above it is the tropopause with clouds of ammonia and hydrogen sulfide. Seasons on Uranus last for several years, during this period one hemisphere is devoid of sunlight. The planet's magnetic field is powerful and complex, its axis is offset from the axis of rotation by 60 degrees.
Rings of uranus
The planet is surrounded by its own, consisting of particles of various diameters. Having a dark color, they do not stand out and are poorly visible. They were considered only in 1977. There are 13 rings - 11 inner and 2 outer, with a colored spectrum.
Satellites
Uranus is not alone in space, its company is divided by 27 large and small satellites. Two of them were discovered in 1787 by William Herschel, 80 years later they discovered the next pair. The last of the five large satellites was spotted almost a century later. These space objects are in the shape of a ball, their bodies are made of ice and stone. Each of them has its own characteristics: - the moon closest to Uranus, - has a very dark surface, - the youngest and lightest, - cut with craters, traces of past volcanic activity. similar in size and appearance to Oberon are the two largest satellites. 22 objects were discovered later, with the help of powerful telescopes and apparatus "". For titles, it is customary to use the names of the characters in the works of Shakespeare and Pope.
The main parameters of the planet
Weight: 86.832 x 10 * 24 kg
Volume: 6833 x 10 * 10 km3
Average radius: 25362 km
Average diameter: 50,724 km
Average density 1.270 g / cm 3
The first space speed: 21.3 km / s
Acceleration of gravity: 8.87 m / s 2
Natural satellites: 27
The presence of rings - yes
Semi-major axis: 2872460000 km
Orbital period: 30685.4 days
Perihelion: 2,741,300,000 km
Aphelios: 3003,620,000 km
Average orbital speed: 6.81 km / s
Orbit inclination: 0.772 °
Orbital eccentricity: 0.0457
Sidereal period of rotation: 17.24 hours
Length of a Day: 17.24 hours
Axial tilt: 97.77 °
Opening date: 13 March 1781
Minimum distance from Earth: 2,581,900,000 km
Maximum distance from Earth: 3,157,300,000 km
Maximum apparent diameter from Earth: 4.1 arc seconds
Minimum apparent diameter from Earth: 3.3 arc seconds
Maximum magnitude: 5.32
Uranus is located at a distance of about 2.88 billion km or 19.2 astronomical units (AU) from the Sun. Since the planet follows an elliptical orbit around the Sun, the numbers above represent the average distance between the planet and the Sun. At the closest point to the Sun, also known as the perihelion position, Uranus is located at 2.75 billion km, or 18.4 AU. e. from the Sun. At the aphelion position or at the most distant point, Uranus moves away from the Sun by 3 billion km, or 20.1 AU. e.
What is the distance between Uranus and Earth?
The distance from Uranus to Earth is constantly changing depending on the movements of both planets in their orbits. The closest distance between the two planets is 2.57 billion km, and the farthest distance is 3.15 billion km.
Who Discovered Uranus?
Sir William Herschel, an astronomer from Britain, observed Uranus on March 13, 1781. He left notes of what he saw in the garden of his home in Somerset, England, and reported the discovery on April 26, 1781, but he mistook the planet for a comet.
How did Uranus get its name?
The planet received its name directly from the name of the deity of the sky from Greek mythology- Uranus.
What is Uranus' density?
The density of Uranus is 1.27 g per cm³, which is the second lowest density indicator among the planets in the solar system.
What is the diameter of Uranus?
The diameter of Uranus is 51,118 km, which is more than 4 times the diameter of our planet.
How many Earths can Uranus contain?
The total volume of Uranus is 6.833 × 1013 km3 and, therefore, it is capable of accommodating 63 of our Earths!
What is Uranus made of?
Uranus is the second least dense planet in the solar system after Saturn. This fact gives an idea of its composition. The planet is a collection of frozen methane, ammonia and water. The exact mass of the ices of Uranus is unknown and is believed to be between 9.3 and 13.5 Earth masses. Hydrogen and helium make up the rest of the planet's mass. Uranus consists of three main layers: the inner one is a rocky core, the middle one is a mantle of ice and an outer gaseous layer that includes hydrogen and helium.
How many rings does Uranus have?
Uranus is surrounded by 13 known rings, ranging from about 38,000 km to about 98,000 km. They are formed, as a rule, from relatively large bodies with a diameter of 0.2-20 m.
Atmosphere of Uranus
Uranus has a unique atmosphere made up of three layers: the troposphere, stratosphere, and thermosphere. The planet's atmosphere is considered the coldest in the solar system and can cool down to temperatures of -224º C. The lower atmosphere is rich in volatile substances such as methane, water and ammonia. The upper atmosphere is mostly hydrogen and helium.
How many satellites does Uranus have?
Uranus has 27 natural satellites. However, the moons of Uranus are the smallest among the moons of the others. Uranus' largest satellite, Titania, has a radius of 788.9 km, making it the eighth largest satellite in the solar system. Satellites usually consist of rock and ice in a ratio of about 1: 1.
What is the temperature of Uranus?
Uranus is one of the. The temperature near the cloud tops of the planet can drop to -216 ° C. The lowest temperature recorded in the tropopause of Uranus is -224 ° C.
Can Uranus Support Life?
It is rather difficult to answer the question of whether Uranus will be able to support life, since there are conditions on the planet that both promote and also hinder the survival of living organisms. Uranus is abundant in methane, which is a key biosignature. There is a possibility that a liquid ocean made of water is present near the planet's core. The bad news, though, is that there is tremendous pressure in the heart of the planet that no life form we know can withstand. In addition, Uranus has the coldest atmosphere in the solar system. Thus, no earthly life cannot survive in such extreme conditions, but specially adapted extraterrestrial life can be used.
How long is one day on Uranus?
A day on Uranus is shorter than on Earth and lasts 17 hours, 14 minutes and 24 seconds.
What is the length of a year on Uranus?
It takes Uranus 84 Earth years to orbit the Sun.
Is Uranus an Inner or Outer Planet?
Uranus is the outer planet of the solar system, which is determined by its distance from the sun.
The seventh planet of the solar system - Uranus - was discovered only in 1781 and was named after the ancient Greek god who was the father of Kronos. This planet is classified as one of the gaseous giant planets, along with Jupiter, Saturn and Neptune.
Ulyam Herschel, who discovered Uranus, first mistook it for a comet. He watched the constellation Taurus, and drew attention to the celestial body, which was in that place, which should have been empty, judging by the star charts of that time. The object was clear enough and moved slowly relative to the stars.
He shared his observation with fellow astronomers, mathematicians and other scientists. European astronomers began to study the object, its distance, mass, orbit and other characteristics. Russian scientist Andrey Leksel, determined the distance between the Sun and Uranus, it was as much as 18 AU. e. (2.8 billion km). So, after 2 months, after many hours of daily observations, scientists were convinced that Herschel had discovered not a comet, but a distant seventh planet. For his discovery, he was awarded a lifetime monetary payment of 200 pounds sterling and was awarded the order. This was the first planet discovered in modern times. Uranus has expanded the boundaries of the solar system in the eyes of man since Antiquity.
The structure of Uranus
As observations from satellites show, an iron-stone core with a temperature of about 7000 K is present on Uranus, but rivers and oceans cannot be observed. The absence of metallic hydrogen reduces the amount of heat emitted by the planet by up to 30%, therefore Uranus receives 70% of its thermal energy from the Sun. A dense, very dense atmosphere immediately begins behind the core, about 8 thousand km thick. Chemical composition the atmosphere of Uranus is as follows: 83% hydrogen (H2), 15% helium (He) and about 2% methane (CH4). Methane, like hydrogen, takes an active part in the absorption of solar radiation, and, consequently, infrared and red spectra. This explains the blue-green color of the planet. Winds in the middle layers, moving at a speed of 250 m / s.
Uranus axis tilt
Uranus is a unique planet in the solar system. The tilt of the axis of rotation is about 98 °, which means that the planet is practically heaped on its side. For clarity: if all the planets look like a spinning top, then Uranus is more like a rolling bowling ball. Due to such an unusual situation, the change of day and night and seasons on the planet, the flow, to put it mildly, non-standard. It turns out that 42 years, one pole is in darkness, the sun shines on the other, and then they change. Scientists explain such a strange position of the planet, a collision with another celestial body(possibly with another planet) that happened millions of years ago.
Moons of Uranus
At the beginning of the third millennium, 27 satellites of the planet Uranus were discovered and explored. The main ones are the 5 largest satellites. The largest satellite, Titania, has a diameter of only 1570 km, which is very small compared to the satellites of other planets. Oberon is the second largest satellite of Uranus. He and Titania were discovered by the same Herschel, who discovered the planet itself. Then there are even smaller satellites: Umbriel, Ariel and Miranda. An interesting fact is that the names of all the moons of Uranus were given in honor of the heroes of the immortal works of William Shakespeare.
Uranus characteristics
Weight: 8.69 * 1025 kg (14 times more earth)
Diameter at equator: 51,118 km (4 times the size of Earth)
Pole diameter: 49,946 km
Axis tilt: 98 °
Density: 1.27 g / cm³
Top layer temperature: about –220 ° C
Period of revolution around the axis (day): 17 hours 15 minutes
Distance from the Sun (average): 19 AU. e. or 2.87 billion km
Orbital period of the Sun (year): 84.5 years
Orbital speed: 6.8 km / s
Orbital eccentricity: e = 0.044
Orbital inclination to ecliptic: i = 0.773 °
Free fall acceleration: about 9 m / s²
Satellites: there are 27
General information about Uranus
Uranus is the seventh planet in the distance from the Sun (the seventh planet in the solar system).
Uranus belongs to the ice giants and is named after the Greek god of the sky, Uranus.
Uranus currently has 27 natural satellites.
Uranus' neighbors are Jupiter and Neptune, behind which the Kuiper belt begins.
Just like the gas giants in the solar system, Uranus has a magnetosphere.
The orientation of Uranus in space differs from the rest of the planets of the solar system. Its axis of rotation lies "on its side" at an angle of 97.86˚ relative to the plane of the planet's orbit.
The Standard Model of Uranus assumes that it consists of three parts: in the center - a rocky core, in the middle - an ice shell, outside - a hydrogen-helium atmosphere.
Uranus has a faint ring system composed of very dark particles ranging in diameter from micrometers to fractions of a meter.
Orbit of Uranus
The average distance from Uranus to the Sun is 2.8 billion kilometers (19.1914 astronomical units).
Perihelion (orbital point closest to the Sun): 2.749 billion kilometers (18.38 AU)
Aphelios (orbital point farthest from the Sun): 3.004 billion kilometers (20.08 AU).
The average speed of movement of Uranus in orbit is about 6.81 kilometers per second.
The planet makes one revolution around the Sun in about 84 Earth years.
A year on the planet is 369.66 Uranian days.
The distance from Uranus to Earth ranges from 2.6 to 3.15 billion kilometers.
3D model of Uranus
Physical characteristics of Uranus
Uranus is the third largest planet in the solar system and fourth by mass.
Uranus is the coldest planet in the solar system with a minimum temperature of -224 ° C.
The average radius of Uranus is 25 362 ± 7 kilometers, that is, about 4 Earth radii.
The surface area of Uranus is 8.1156 billion square kilometers.
The average density of Uranus is 1.27 grams per cubic centimeter.
The acceleration due to gravity on Uranus is 8.87 meters per second squared (0.886 g).
The mass of Uranus is 8.6832 x 10 25 kilograms, which is about 14.6 Earth masses.
Voyager 2 discovered a specific magnetic field in Uranus, which is 1/3 of the planet's radius displaced from its geometric center and tilted by 59˚ relative to the axis of rotation.
Comparative sizes of Uranus and Earth
Atmosphere of Uranus
The atmosphere of Uranus is conventionally divided into 3 parts: troposphere, stratosphere and thermosphere / atmospheric corona. The mesosphere is missing.
The main components of Uranus' atmosphere are hydrogen (about 83 ± 3%), helium (15 ± 3%) and methane (2.3%).
Winds on Uranus can reach 900 kilometers per hour.
Due to the tilt of the axis (97.86˚), the polar regions of Uranus receive more solar energy during the year than the equatorial ones. However, Uranus is warmer in the equatorial regions than in the polar regions. The mechanism causing such a redistribution of energy remains unknown.
Uranus shows signs of seasonal changes and weather activity caused by the planet's approach to the equinox.
Exploration of Uranus
Uranus was discovered on March 13, 1781 by the English astronomer William Herschel, up to this point it was observed 21 times, but astronomers mistook it for a star.
In 1789, William Herschel claimed to have seen rings on Uranus, but the ring system was unambiguously confirmed only in 1977, and their reddish tint only in 2006.
The only visit to the vicinity of Uranus in the history of astronautics in 1986 was made by the American spacecraft Voyager 2. He transmitted close-up images of Uranus to Earth in the visible spectrum, showing a "featureless" planet without cloud stripes and atmospheric storms.
Uranus is the least massive of all the giant planets in the solar system.
Each pole of Uranus is in darkness for 42 Earth years, and for the next 42 years it is bathed in sunlight.
With a clear dark sky, Uranus in opposition is visible to the naked eye, and with binoculars it can be observed even in a city.
Uranus became the first planet discovered with a telescope.
Uranus is the only large planet in the solar system whose name does not come from Roman, but from Greek mythology.
The Uranus satellite system is the least massive among satellite systems gas giants. Even the total mass of the largest five satellites will not be even half the mass of Triton, the satellite of Neptune.
The names of the moons of Uranus are chosen from the names of the characters in the works of William Shakespeare and Alexander Pope.