Our solar system is rich in many interesting phenomena. Dwarf planets deserve special attention. They are objects orbiting the sun, with some similarities to asteroids.
Dwarf planets of our solar system
Our solar system is rich in many interesting phenomena. Among them deserve the greatest attention. All of them are objects orbiting the Sun, with some similarities to asteroids. In this article we will look at what it is in general terms. Then we’ll take a closer look at the dwarf planet Sedna.
Main characteristics of objects
In relation to dwarf planets, there are requirements from the International Astronomical Union. Objects must strictly comply with them. Otherwise, they cannot be called dwarf planets, but must have a different name. So, the objects in question meet the following requirements:
- have a weight that allows them to maintain hydrostatic equilibrium and have a spherical appearance;
- are not able to clear the surroundings of their own orbit from other space objects;
- revolve around the Sun;
- should not be satellites of other planets.
Today, only six dwarf planets are known. These include Sedna, Eris, Makemake, Haumea, Pluto and Ceres. Each of the listed objects differs from the other as much as the “large” planets differ from each other.
It was possible to study only two of the six “dwarfs”. One of NASA's interplanetary stations is still in orbit of one dwarf planet - Ceres. High-quality images of the surface of the celestial body were obtained. Photos taken by AMC Dawn Station. This is an advanced spacecraft. Its engines operate on ion thrust. Therefore, with the help of AMC Dawn, it became possible to study several space objects at once.
It was this device that for the first time in history entered the orbit of an asteroid and collected all the necessary information about it. After which he retired to explore the next celestial body - the dwarf planet Ceres. The use of this automatic station made it possible to make a breakthrough in the study of the main asteroid belt. AMC Dawn has created an accurate and detailed map of the surface of asteroids and dwarf planets.
Two years ago, the New Horizons spacecraft made its first close approach to the largest of the six objects, Pluto. As a result, photographs of its surface were also obtained. The appearance of the remaining dwarf planets is currently unknown to humanity.
The list of objects under consideration may be expanded. Astronomers have about forty candidates for the title of “dwarf planet.” All of them are located outside of Neptune. But there is no clear data about these objects. Therefore, they are not yet officially classified as dwarf planets. There is also an opinion that at least two thousand objects of this type are located in the Kuiper belt, the Oort cloud and the scattered disk.
It is safe to say that extrasolar dwarf planets also exist. But nowadays they are unlikely to be open. Modern telescopes do not provide this opportunity. But science does not stand still. Perhaps in the near future we will learn a lot of interesting things.
Sedna: what do astronomers know?
There is a popular theory according to which the Sun, through its gravity, stole several hundred dwarf planets and asteroids from another star flying nearby. For the most part, this was all considered a wild guess. But these days there is already some confirmation of this hypothesis.
Astronomers have been attracted by the dwarf planet Sedna. It and several neighboring celestial objects move in rather strange orbits. In particular, Sedna is the most distant object in our Solar System. Moreover, the closest point of its orbit is located 76 AU from the star, and the farthest is located at 1007 AU. e. This object has a huge orbital period. It is eleven thousand four hundred and eighty-seven years. It is considered the longest among large celestial bodies.
Scientists tried to figure out the nature of this strange behavior of sednoids. They first tried to do this in 2003. That's when they were discovered. At first, scientists could not find a rational explanation. The theory was then put forward that the orbits of the sednoids were elongated by a passing star about four billion years ago.
Subsequently, computer modeling of the previously described hypothesis was carried out. This happened at the Leiden Observatory. It turned out that the star flying nearby did not affect the orbits of the sednoids. Rather, it was the Sun that attracted them to itself.
During the study, more than ten thousand variations of scenarios were taken into account, which took into account different combinations of distances, speed of passage and masses of stellar systems. The simulation was carried out under the guidance of famous astronomer Lucy Zhilkova.
The calculations carried out allowed us to calculate the most likely scenario. The star passing by was eighty percent larger than the Sun. The maximum convergence indicator was about thirty-four billion kilometers. In this case, the exchange of objects occurred on both sides. Some objects were added to the orbit of the Sun, while others, on the contrary, went to another system. This event apparently occurred about four billion years ago.
The work carried out by Zhilkova received good reviews and recognition from scientists around the world. However, we should not forget that this is just a theory, albeit a highly probable one. It still requires additional confirmation. This can be achieved by performing chemical analysis. If its results differ from data from trans-Neptunian objects, this will mean that the sednoids are of foreign origin. It is not possible to see the results of this analysis in the near future.
There is also a theory that claims the presence of an as yet undiscovered planet, whose orbit is located hundreds of AU. e. from the Sun. It is she who makes adjustments to Sedna’s flight path. Again, this is just a bold assumption that requires serious scientific study.
Results
There are many gaps in the study of dwarf planets. But with the development of new space exploration technologies, all of them will be quickly replenished. Modern scientific stations pay great attention to the study of this issue.
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Introduction
2. Historical background
3. List of dwarf planets
4. Mass restrictions
8. Makemake
Conclusion
Bibliography
Application
Introduction
In this part of my essay, I would like to justify the reasons for my choice of the topic of dwarf planets.
It seemed to me that they [the dwarf planets] are very similar to us, eleventh graders: we are no longer small asteroids moving in orbit around the Sun, but not yet planets with their own gravity. Perhaps such a comparison may seem too romantic to some, but, nevertheless, it was this closeness and similarity that attracted me to this topic.
dwarf planet sign
1. Dwarf planet: term and signs
So what is a dwarf planet?
A dwarf planet, as defined by the International Astronomical Union, is a celestial body that:
Does not dominate its orbit (cannot clear space from other objects).
2. Historical background
The term "dwarf planet" was adopted in 2006 as part of the classification of bodies orbiting the Sun into three categories. Bodies large enough to clear the environs of their orbit are defined as planets, and bodies not large enough to achieve even hydrostatic equilibrium are defined as small solar system bodies or asteroids. Dwarf planets occupy an intermediate position between these two categories. This definition has met with both approval and criticism, and is still disputed by some scientists. For example, as the simplest alternative, they propose a conditional division between planets and dwarf planets based on the size of Mercury or even the Moon: if larger, then it is a planet, if smaller, then it is a planetoid.
In 2006, the IAU officially named three bodies that immediately received the classification of dwarf planets - Ceres, Eris and Pluto. Later, two more objects were declared dwarf planets. The term "dwarf planet" should be distinguished from the concept of "minor planet", which is used to describe asteroids.
3. List of dwarf planets
The International Astronomical Union officially recognizes five dwarf planets: Ceres, Pluto, Haumea, Makemake, Eris; however, it is possible that at least 40 more of the known objects in the Solar System belong to this category. Scientists estimate that up to 200 dwarf planets may be discovered in the Kuiper belt and up to 2,000 dwarf planets beyond it. Because Pluto shares its orbital space with many other objects in the Kuiper Belt - the ring of icy debris beyond Neptune's orbit - it was not included in the list of planets. Thus, Pluto was classified as a dwarf planet. It is interesting that from this list only he [Pluto] was “demoted”, becoming a dwarf planet and losing the status of a planet, while the rest were, on the contrary, “promoted”, ceasing to be just one of the asteroids.
Three large objects in the asteroid belt (Vesta, Pallas and Hygiea) would have to be classified as dwarf planets if it turns out that their shape is determined by hydrostatic equilibrium. To date, this has not been convincingly proven.
4. Mass restrictions
The lower and upper limits for the size and mass of dwarf planets are not specified in the IAU decision. There are no strict restrictions on the upper limits, and an object larger or more massive than Mercury with an unrefined orbital neighborhood can be classified as a dwarf planet.
The lower limit is determined by the concept of a hydrostatically equilibrium shape, but the size and mass of the object that has achieved this shape is unknown. Empirical observations suggest that they may vary greatly depending on the composition and history of the object. The original IAU preliminary decision defining hydrostatic equilibrium applied "to objects with a mass greater than 51,020 kg and a diameter greater than 800 km", but this was not included in the final decision 5A, which was approved.
According to some astronomers, the new definition means the addition of up to 45 new dwarf planets.
Pluto was discovered by Clyde Tombaugh in 1930 during the search for the mysterious Planet X, which was disrupting Neptune's orbit.
Pluto was originally thought to be at least the size of Earth, but it is now known to have a diameter of only 2,352 kilometers - 5 times smaller than Earth's - and a mass only 0.2% of Earth's.
Pluto has an extremely elongated elliptical orbit, which is not in the same plane as the orbits of the eight planets in the solar system. On average, the dwarf planet orbits the Sun at a distance of 5.87 billion kilometers, completing one revolution every 248 years.
Due to its distance from the star, Pluto is one of the coldest places in our system. The temperature on its surface hovers around minus 225 degrees Celsius.
Pluto has 4 known moons: Charon, Nyx, Hydra, and a recently discovered tiny moon called P4 (the final name will probably be Cerberus). Nyx, Hydra and P4 are relatively small, Charon is only half the size of Pluto itself, and the center of mass around which they orbit is outside their bodies. For this reason, most astronomers call them a double dwarf planet.
Although Pluto is difficult to study due to its remoteness, scientists have been able to calculate its approximate composition: it is 70% rock and 30% ice. The dwarf planet's surface is covered mostly with frozen nitrogen. There is a very thin atmosphere, extending 3,000 kilometers into space and consisting mostly of nitrogen, methane and carbon monoxide.
In a few years, Pluto will finally get a good look: NASA's New Horizons probe will fly by the dwarf planet in July 2015, showing such a cold and distant world for the first time in history.
Caltech astronomer Mike Brown led the team that discovered Eris in 2005. The search was stimulated by the IAU's intention to classify Pluto into the newly created category of dwarf planets, which happened a year later.
The decision to give this dwarf planet such a name remains controversial. Eris is the Greek goddess of discord and hostility, who caused envy and jealousy among the goddesses, which led to the Trojan War. The only known moon of Eris was named after the daughter of the goddess, Dysnomia, who “worked” in the Pantheon as the spirit of lawlessness.
Eris is almost the same size as Pluto, but 25% more massive than it, which is explained by its higher content of rock and less ice. However, its surface also consists mainly of nitrogen ice.
Like Pluto, Eris has a highly elliptical orbit. Eris is even more distant from the sun, its orbit is at an average distance of 10.1 billion kilometers from the sun. One Eridanian year is 557 years.
Huamea was discovered in the Kuiper Belt near the orbit of Pluto in late 2004 by Brown's team, and has become one of the strangest objects in the solar system.
This dwarf planet is 1,930 kilometers across, almost the size of Pluto, but three times lighter. This is mainly due to its non-spherical shape. Most of all, Huamea resembles an American football.
This dwarf planet makes one revolution around its axis in just 4 hours, which makes it one of the fastest rotating bodies in our system. This ultra-high rotation speed is responsible for the dwarf planet's elongated shape.
Huamea, named after the Hawaiian goddess of childbirth, has two satellites named for her daughters: Hi'iaka and Namaka.
It was recently discovered that 75% of Huamea's surface is covered with crystallized water ice, similar to the ice in a refrigerator freezer. It takes energy for ice to maintain this structured shape. Astronomers speculate that the energy may come from the decay of radioactive elements within Haumea, as well as from heat generated by tidal forces in gravitational interaction with its moons. Huamea completes a revolution around the Sun in 283 years.
8. Makemake
Brown's team also discovered Makemake in 2005. Astronomers have not yet established the exact size of this dwarf planet; it is approximately three-quarters the size of Pluto. This makes this object the third largest dwarf planet after Pluto and Eris.
Makemake is the second brightest Kuiper Belt object after Pluto and can be seen even with a good amateur telescope. Like Huamea, Makemake is named after a Polynesian deity - this time after the name of the creator of mankind and the god of fertility in the Rapa Nui pantheon - the indigenous inhabitants of Easter Island.
Like Pluto and Eris, Makemake appears reddish in the visible spectrum. Scientists believe that the surface of the dwarf planet is covered with frozen methane. Makemake has no moons discovered, which is unique among dwarf planets.
Ceres is the only dwarf planet not in the Kuiper belt. Its orbit passes through the asteroid belt between the orbits of Mars and Jupiter, making one revolution every 4.6 years.
Ceres is the largest object in the asteroid belt, and contains about a third of the belt's total mass. Meanwhile, being only 950 kilometers across, it is the smallest known dwarf planet. Ceres is the goddess of fertility and motherhood in ancient Roman mythology.
This dwarf planet was discovered much earlier than others due to its proximity. Italian astronomer Giuseppe Piazzi discovered it in 1801. For the next half century, astronomers considered it a real planet, until it became clear that it was just one of many objects in the asteroid belt.
Today, most astronomers classify Ceres as a protoplanet, believing that it could have grown into a full-fledged planet like Mars or Earth if Jupiter had not interrupted this process with its powerful gravity in ancient times.
Scientists believe that Ceres consists of a rocky core surrounded by a thick mantle of water ice. Some researchers even suggest the existence of an ocean of liquid water under a layer of ice.
In a few years, the whole world will be able to learn a lot about this dwarf planet - in February 2015, NASA's Down spacecraft, currently orbiting the asteroid Vesta, will arrive at Ceres to study it in detail.
In conclusion, I would like to summarize the most important information about dwarf planets:
A dwarf planet is a celestial body that:
Orbits the Sun;
Has sufficient mass to maintain hydrostatic equilibrium under the influence of gravity and have a close to round shape;
Not a satellite of the planet;
Does not dominate its orbit (cannot clear space from other objects);
The International Astronomical Union officially recognizes five dwarf planets: Ceres, Pluto, Haumea, Makemake, and Eris. Because Pluto shares its orbital space with many other objects in the Kuiper Belt - the ring of icy debris beyond Neptune's orbit - it was not included in the list of planets. Thus, Pluto was classified as a dwarf planet.
I hope that this essay was educational and useful for all readers. After all, space is one of the most mysterious, unknown and interesting topics for discussion. Moreover, as Fred Hoyle wrote, space is only an hour away if your car could drive vertically.
Bibliography
1. http://ru.wikipedia.org/wiki/Dwarf_planet
2. http://scienceevents.ru/posts/3689-dwarf-planets-solar-system/
3. http://www.lassy.ru/news/karlikovye_planety/2011-08-23-159
Application
Fig.1 Arrangement order of dwarf planets
Fig.2 Dwarf planets compared to Earth
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Review of dwarf planets: Pluto, Eris, Makemake, Haumea, Ceres
Our Solar System is under the constant attention of not only astronomers, but also simply those who like to keep abreast of space events and news. And if such cosmic bodies as Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune are always in the public eye and everyone knows about them, then dwarf planets have become the object of everyone’s attention quite recently.
Pluto
Once a planet, Pluto lost it in 2006 when the International Astronomical Union first defined the term "planet." At the moment it is considered the largest dwarf planet in the solar system. However, the head of the New Horizons mission, Alan Stern, under whose careful supervision the probe made a successful flight over the surface of Pluto, recently made a very impressive statement. He reported that Pluto is a planet.
To justify his statement, he cited two facts. First, he pointed out that Pluto's shape is completely consistent with mass, and second, he pointed out that this world is incredibly active, with hydrocarbon rain and seismic activity and nitrogen glaciers. The scientist believes that this cosmic body cannot be considered simply a stationary object, the surface of which is covered with rocks and ice. It is very likely that according to his arguments, the status of Pluto may be changed in the near future.
His words were confirmed by recent images taken by the Lorry camera of the New Horizons spacecraft, which indicated that the heart-shaped plain on Pluto has at its very center huge deposits of ice that are in constant dynamics. This indicates the complex geological structure of the dwarf planet. It turned out that the movement of glaciers on the surface is carried out in the same way as on Earth. Recent studies indicate that the chemical composition of this glacier includes nitrogen, methane and carbon dioxide.
But Pluto is far from the only dwarf planet in our solar system discovered to date. We invite you to get acquainted with the lesser-known, but no less interesting dwarf worlds known today.
Eris
The dwarf planet Eris is to some extent responsible for Pluto's "downgrading" to a dwarf planet in 2006. This is a small world that moves in a strange elliptical path around the Sun, it was discovered by astronomer Mike Brown in 2003.
When Eris was first discovered, scientists thought it might actually be even larger than Pluto. Such findings caused controversy among astronomers who wanted the classification of cosmic bodies in the solar system to be revised, which is what happened. But it turned out that its size is smaller and now Eridu has the status of the second largest dwarf planet in the solar system.
Because Eris is so far from Earth and from the Sun (10.18 billion km), makes it a difficult planet to study. Thus, difficulties arose in determining its size. The reason for this is Eris's strong brightness, which can cause its albedo to be inflated. Taking into account the absolute magnitude of the cosmic body, its diameter should be at least 2300 km.
Makemake
Discovered in 2005, the dwarf planet Makemake lies in the Kuiper Belt. This tiny world takes 310 Earth years to complete one revolution around the Sun.
Scientists believe that the dwarf planet is actually reddish-brown in color. And at first glance, this is the dominant color in this part of the space. However, data obtained from the New Horizons probe confirmed that Pluto has a reddish tint, and therefore other objects in the Kuiper Belt also have a predominantly red tint.
According to NASA representatives, signs of frozen nitrogen have been found on the surface of this dwarf planet. In addition, the chemical composition of the cosmic body includes frozen ethane and methane. According to scientists, methane is present on the surface in the form of granules, the diameter of which is at least one centimeter.
Haumea
Haumea moves very quickly. The dwarf planet rotates at such a speed that it completes a full rotation on its axis every four hours. Scientists believe that rotation gave this planet an elongated shape. The dwarf planet—discovered in 2003—also in the Kuiper Belt, orbits the Sun every 285 Earth years, and is not much smaller than Pluto.
Astronomers believe that the surface of Haumea is covered with rocks with an icy crust. Haumea is named after the Hawaiian goddess of fertility.
Ceres
The dwarf planet Ceres is truly a strange and mysterious cosmic body. The small, cratered world is not part of the Kuiper Belt, but that doesn't stop it from orbiting the Sun.
Ceres was discovered in 1801. However, detailed information about it was obtained thanks to data received from NASA's spacecraft Dawn, which has been studying the small world since March 2015. The probe discovered a number of craters with bright spots inside them. Scientists representing the mission are currently unable to provide precise information about the composition of these light-reflecting areas. More accurate data will be obtained when the Rassvet spacecraft enters a lower orbit of Ceres.
“We are now comparing the spots with the reflective properties of salt, but there is no concrete result yet,” Chris Russell, the mission’s principal investigator, said about the nature of the spots. “We look forward to new data and high-resolution photographs following the next orbital phase of the mission.”
And the rest...
NASA scientists believe there may be up to several dozen dwarf planets orbiting the Sun.
They place certain hopes on the New Horizons probe, which is capable of exploring another large area of space. Perhaps in four or five years, he will be able to detect one or more objects in the Kuiper Belt. At the moment, there is a question about funding the mission, but if it receives support from NASA, then perhaps humanity will be able to see more than one new dwarf world in our solar system.
Translation: Nevalenaya T.
Editor: Kolupaev D.
The vast majority of people don't know that Pluto is now a dwarf planet in the solar system. If you don't know, there are now several of them. Of the five officially recognized, Pluto is not even the largest. There are many interesting facts about them that can be found below.
This group of celestial bodies remains the least studied so far due to their distance from the center of our system, but thanks to the constant development of technology, astronomers are constantly filling gaps in their knowledge. The years 2003-2005 were quite fruitful for openings. Modern technology allows you to see even the most distant object.
Pluto
One of the smallest objects in the solar system, with a radius of only 1153 km. The orbital period around the Sun is 90,613 days (about 248 years), and a revolution around its axis takes 6.4 Earth days. For several decades since its discovery in 1930, it was considered the ninth planet, until in 2006 astronomers came to the conclusion that it should still be classified as a dwarf planet in the Kuiper belt, which received its name after the discovery of several similar objects in 2005.
There are currently 5 known satellites accompanying it - the largest of them are Kerberos, Nikta, Styx and Hydra. The orbit of this dwarf planet is elliptical, quite elongated .
Only a few years ago, scientists were able to measure the temperature on the surface of this celestial body. On July 14, 2015, the New Horizons spacecraft made a close flyby of Pluto and transmitted a wealth of data and photographs about it.
Haumea
The fastest rotating of all the planets known today in our system - one revolution around its own axis takes only 4 hours, while a complete flight around the Sun takes 102937 days (almost 282 years). One of the smallest objects, the average radius is only 718 km, and, unlike other celestial bodies, it has an irregular, seemingly flattened shape. At the same time, there are 2 satellites - Hiiaka and Namaka.
Makemake
The size of the third largest is still not known exactly. The average radius is assumed to be approximately 740 to within 17 km. But the length of the year on it was able to be established quite accurately - 111867 days (which is approximately equal to 306 years). No satellites were found in its orbit.
Eris
One of the largest Kuiper belt objects is only slightly larger than Pluto - 1163 km. A revolution around the Sun takes 205,029 days (slightly more than 561 years).
The scientists who discovered it in 2005 were initially confident that they had discovered the 10th planet of the solar system, but it was later recognized as a dwarf planet.
The discovery of this celestial body can be said to mark the beginning of a new era for astronomy, since it was the fact of its discovery that began numerous disputes about the status of Pluto.
Ceres
It is notable for the fact that until quite recently it was in the category of asteroids and ranked first among them in size. The length of the year, compared to other distant dwarf planets, is ridiculous, only 4.6 years.
Compared to others, its diameter is not so impressive and is 975 × 909 km. The period of rotation around the axis lasts about 0.3781 days. No satellites were detected.
Classification
They have their own classification, which does not exist very much and it can be revised in the future based on new scientific discoveries.
> Dwarf planets
All information about dwarf planets Solar system for children: what it is, sizes, list of dwarf planets with photos, large Pluto and Ceres, distance.
Begin explanation for children parents or teachers At school They can do so because the dwarf planets of the Solar System are small worlds, whose size does not allow them to become full-fledged planets. However, they are too large to be moved to another category.
Can explain to the children situation using the example of Pluto. At one time he made a lot of noise, and even now debates about his status continue. It no longer plays the role of the ninth planet and has shifted to the position of dwarf planets.
For the little ones It will be interesting to know that at the moment there may be up to 200 dwarf planets. But not all children and even parents understand the difference between a dwarf and a full-fledged planet. Next, you will learn many interesting facts about the dwarf planets of the solar system, get acquainted with the description of worlds like Pluto and Eris, and also be able to see them in photos, drawings, pictures and diagrams. It is also interesting to understand where the names came from and what the orbits of dwarf planets look like.
Dwarf planets - explanation for children
The basic definition is given by the International Astronomical Union (IAU). According to him, the planet must revolve around the Sun, have sufficient gravity to become a sphere and clear the orbit of small objects. The last requirement will be especially important. Gravity attracts or repels other objects in its orbit. Dwarfs don't have enough of it to match.
As of 2015, the IAU recognizes and lists 5 dwarf planets: Ceres, Pluto, Eris, Haumea and Makemake. There are also candidates (Sedna and Quavare), located beyond the orbit of Pluto, and the object 2012 VP113, which has one of the most distant orbits. NASA believes there are at least 100 more dwarfs waiting to be discovered.
But the debate about Pluto's status is heating up every year. Moreover, the New Horizons mission can play a major role in this.
Many consider the requirement to “clear the orbit” to be something absurd and incorrect. Scientist Alan Stern also stood up for Pluto. At the end of 2014, Harvard-Smithsonian University broadcast “What is a Planet?”, after which the audience voted on Pluto’s planetary status.
Begin explanation for children It is worth noting that Ceres is the earliest and smallest dwarf planet. It was discovered by Italian astronomer Giuseppe Piazzi in 1801. It has a diameter of 950 km, and its mass reaches only 0.015% of the Earth's.
It is so tiny that it is classified as both a dwarf and an asteroid. It makes up ¼ of the mass of all asteroids, but is smaller in size than Pluto. It has an almost round body and a rocky composition with the possibility of water ice. In 2014, an emission of water vapor was observed from two areas of the dwarf.
Pluto is the most famous and popularly discussed dwarf. It was discovered in 1930, and survived as a planet until 2006. Its orbit is unusual because it periodically becomes closer to the Sun than Neptune.
Although it reaches only 0.2% of the Earth's mass and 10% of the mass of our Moon, its gravity is enough to hold 5 satellites. Contact with the huge moon Charon leads scientists to consider them as a binary system because they rotate around a point between themselves.
Eris was once considered the largest dwarf (27% larger than the mass of Pluto) with a diameter of 2300-2400 km. It was she who forced the IAU to take a fresh look at the definition of planets. Its orbit is unstable, so Eris crosses the path of Pluto and even Neptune. It takes 557 years to complete its orbital path. At its farthest point it extends beyond the Kuiper Belt.
They were recently given names. Haumea attracts attention with its shape - an ellipsoid, which is one of the planetary criteria. Due to its rapid rotation, it is elongated, and its mass is three times less than Pluto. The axial rotation takes 4 hours, which may be explained by an early collision. It also has a red spot and a layer of crystalline ice. It is the only object in the Kuiper Belt (not counting Pluto) that has multiple moons.
Makemake is also interesting because it has no companion. Because of this, it is difficult to determine its mass, although its diameter is 2/3 smaller than that of Pluto. Interestingly, if new requirements from the IAU had not appeared, Makemake could have been considered a planet.
Plutoids
Pluto, Haumea, Eris and Makemake are called plutoids. This is a subdivision of dwarfs with orbits beyond Neptune. Sometimes they are also called ice dwarfs due to the frost on the surface and their small size. The outer planets demonstrate their contact with the plutoids. For example, Neptune's largest moon Triton may turn out to be a plutoid.
If you want to supplement the characteristics of dwarf planets, you can always use the 3D model of the Solar System on the website and look at maps of dwarf planets, the features of their surface and their orbital motion around the Sun. It would also be interesting for children to look at the worlds through an online telescope in real time, but they are too small and far away for such observation. Therefore, consider photos, pictures and images from spacecraft.
Objects beyond the orbit of Neptune.