Astronomers have been studying asteroids for a long time, but the world community became interested in them only about 10 years ago, after mass media reported the risk of a collision with the celestial body Apophis. This catastrophe would be the death of a quarter of the world's population.
Later, when scientists recalculated the asteroid's trajectory, the panic passed, but interest in celestial pebbles and astronomy remained. Which of the asteroids are the most "visible" and valuable? The TOP 10 included:
Ceres
The size of this asteroid reaches almost 950 kilometers. The discovery of this celestial body took place in 1801, and since then, as soon as it was not called. Initially a full-fledged planet, after an asteroid, and in 2006 it was recognized as a dwarf planet, since Ceres is by far the most powerful object in the asteroid belt.
Ceres looks like a sphere, which is a bit surprising for an asteroid, and its rocky core and crust are made up of minerals and frozen water. Earthlings can not be afraid of a collision with Ceres in the coming millennia, since the point of its orbit is removed from the Earth by as much as 263 million kilometers. Therefore, scientists show exclusively scientific interest.
Pallas
It surprises with its rather big size - 532 kilometers. Pallas is also part of the asteroid belt, and high hopes are placed on it because of the silicon that it is rich in. Perhaps someday Pallas will be a valuable source of silicon for us. Discovered at the beginning of the 20th century, it is now being diligently studied by scientists around the world. There is not much information about the asteroid.
Vesta
The diameter of this asteroid is 530 kilometers. But, even with the smaller size, Vesta has the championship in the “heavyweight” category. The core of the asteroid is heavy metal, and the crust is rock. Due to its differences, Vesta is able to reflect four times more sunlight than other asteroids. It is because of this that it is sometimes possible to see it from Earth. This event happens every three or four years. Therefore, the asteroid was considered an ordinary but unknown planet for a long time.
Hygiea
This asteroid cannot be called small, its diameter is about 400 kilometers. But Hygiea is very dim, so it was discovered later than its colleagues. Hygiea is absolutely typical of the most common type of asteroid and has a carbonaceous content. When Hygiea is as close as possible to the planet Earth, it can be seen armed with binoculars.
Interamnia
An asteroid with a diameter of 326 kilometers, although considered quite large, is still a little-studied celestial object to this day. And the reason is that Interamnia - heavenly body rare spectral type F.
Modern scientists have not yet figured out what astronomical objects of this class consist of, and are also in the dark about their internal structure. What can I say, even Interamnia's form is still a mystery! Today it is the least known celestial object.
Europe
This asteroid was discovered a long time ago, since that time more than one hundred and fifty years have passed. Its diameter is about 302 kilometers. Europa is distinguished by its oblong orbit, which is why the distance from the asteroid to the Sun fluctuates all the time.
If life existed on Europa, it would be inhabited by mutants with increased adaptability. The density of Europa is almost the same as water, so the surface of the asteroid is porous. Reminiscent of flying pumice, spinning in the Great Ring of Asteroids.
David
The diameter of this celestial object is estimated differently, mainly it fluctuates in the range of 270-326 kilometers. Davida owes her name to her discoverer, Raymond Dugan, who dedicated this asteroid to astronomy professor David Todd. Subsequently, "David" was changed into a female name, since then it was customary to give celestial bodies only female names, and tried to take them from Greek mythology.
Silvia
Celestial body with a diameter of 232 kilometers. Sylvia, like Europe, is porous, but for different reasons. The asteroid is made of rubble, which is held only by the force of gravity. Sylvia is also famous for being the first triple asteroid to have as many as two satellites.
Hector
An amazing asteroid that looks like either a peanut or a dumbbell. Due to its strange shape, it has become the cause of controversy about its origin, someone considers it man-made, other scientists prove its natural origin.
Hector has his own, as yet unnamed, moon. Hector is also interesting for his origin. So, it contains rocks and ice. This composition is found in Kuiper belt asteroids, which means that Hector also came from there.
Euphrosyne
A celestial body with a diameter of 248-270 kilometers rotates very quickly. Its density is very high, but scientists explain this by the “largeness” of Euphrosyne. By the way, asteroids never cease to amaze the public! Most recently, the celestial body UW-158 passed at a distance of 2.4 million kilometers from our planet. Surprisingly, its core contains almost 100 million tons of platinum. Such a discovery, according to scientists, will bring many benefits in the future.
Asteroids are relatively small celestial bodies that orbit around the sun. They are significantly inferior in size and mass to the planets, have irregular shape and have no atmosphere.
In this section of the site, the site everyone can learn a lot interesting facts about asteroids. You may already be familiar with some, others will be new to you. Asteroids are an interesting spectrum of the Cosmos, and we invite you to familiarize yourself with them in as much detail as possible.
The term "asteroid" was first coined by the famous composer Charles Burney and used by William Herschel on the basis that these objects, when viewed through a telescope, look like dots of stars, while the planets look like disks.
There is still no exact definition of the term "asteroid". Until 2006, asteroids were called minor planets.
The main parameter by which they are classified is body size. Asteroids include bodies with a diameter of more than 30 m, and bodies with a smaller size are called meteorites.
In 2006, the International Astronomical Union classified most asteroids as small bodies of ours. solar system.
To date, hundreds of thousands of asteroids have been identified in the solar system. As of January 11, 2015, the database contains 670474 objects, of which 422636 have orbits, they have an official number, more than 19 thousand of them had official names. According to scientists, in the solar system there can be from 1.1 to 1.9 million objects larger than 1 km. Most of the asteroids known so far are within the asteroid belt between the orbits of Jupiter and Mars.
Most big asteroid in the solar system - Ceres, which has dimensions of approximately 975x909 km, but since August 24, 2006, it has been classified as a dwarf planet. The remaining two large asteroids (4) Vesta and (2) Pallas have a diameter of about 500 km. Moreover, (4) Vesta is the only object of the asteroid belt that is visible to the naked eye. All asteroids that move in other orbits can be traced during the period of passage near our planet.
As for the total weight of all asteroids in the main belt, it is estimated at 3.0 - 3.6 1021 kg, which is approximately 4% of the weight of the moon. However, the mass of Ceres accounts for about 32% of the total mass (9.5 1020 kg), and together with three other large asteroids - (10) Hygiea, (2) Pallas, (4) Vesta - 51%, that is, most asteroids differ negligible by astronomical standards.
Exploring asteroids
After William Herschel discovered the planet Uranus in 1781, the first discoveries of asteroids began. The average heliocentric distance of asteroids corresponds to the Titius-Bode rule.
Franz Xaver created a group of twenty-four astronomers at the end of the 18th century. Beginning in 1789, this group specialized in searching for a planet that, according to the Titius-Bode rule, should be located at a distance of about 2.8 astronomical units (AU) from the Sun, namely between the orbits of Jupiter and Mars. The main task was to describe the coordinates of the stars located in the area of the zodiac constellations at a particular moment. The coordinates were checked on subsequent nights, objects moving over long distances were identified. According to their assumption, the displacement of the desired planet should be about thirty arc seconds per hour, which would be very noticeable.
The first asteroid, Ceres, was discovered by the Italian Piacio, who was not involved in this project, quite by accident, on the very first night of the century - 1801. The other three - (2) Pallas, (4) Vesta and (3) Juno - were discovered in the next few years. The most recent (in 1807) was Vesta. After another eight years of meaningless searching, many astronomers decided that there was nothing more to look for, and gave up any attempt.
But Karl Ludwig Henke showed perseverance and in 1830 he again began to search for new asteroids. After 15 years, he discovered Astrea, which was the first asteroid in 38 years. And after 2 years I discovered Hebe. After that, other astronomers joined the work, and then at least one new asteroid was discovered per year (except for 1945).
The method of astrophotography for searching for asteroids was first used by Max Wolf in 1891, according to which asteroids left light short lines in a photo with a long exposure period. This method significantly accelerated the detection of new asteroids compared to the methods of visual observation used previously. Max Wolf single-handedly discovered 248 asteroids, while few before him managed to find more than 300. Nowadays, 385,000 asteroids have an official number, and 18,000 of them also have a name.
Five years ago, two independent teams of astronomers from Brazil, Spain and the US announced that they had simultaneously detected water ice on the surface of Themis, one of the largest asteroids. Their discovery made it possible to find out the origin of water on our planet. At the beginning of its existence, it was too hot, unable to hold a large amount of water. This substance appeared later. Scientists have suggested that comets brought water to Earth, but only the isotopic compositions of water in comets and terrestrial water do not match. Therefore, it can be assumed that it hit the Earth during its collision with asteroids. At the same time, scientists discovered complex hydrocarbons on Themis, incl. molecules are the precursors of life.
Name of asteroids
Initially, asteroids were given the names of the heroes of Greek and Roman mythology, later the discoverers could call them whatever they wanted, up to their own name. At first, asteroids were almost always given female names, while only those asteroids that had unusual orbits. Over time, this rule has ceased to be respected.
It is worth noting that not every asteroid can get a name, but only one whose orbit is reliably calculated. Often there were cases when the asteroid was named many years after the discovery. Until the orbit was calculated, the asteroid was given only a temporary designation representing the date of its discovery, such as 1950 DA. The first letter means the number of the crescent in the year (in the example, as you can see, this is the second half of February), respectively, the second one indicates its serial number in the indicated crescent (as you can see, this asteroid was discovered first). The numbers, as you might guess, represent the year. Because the English letters 26, and 24 crescents, two letters were never used in the designation: Z and I. In the event that the number of asteroids discovered during the crescent is more than 24, scientists returned to the beginning of the alphabet, namely, writing the second letter - 2, respectively , on the next return - 3, and so on.
The name of the asteroid after receiving the name consists of a serial number (number) and the name - (8) Flora, (1) Ceres, etc.
Determining the size and shape of asteroids
The first attempts to measure the diameters of asteroids, using the method of direct measurement of visible disks with a thread micrometer, were made by Johann Schroeter and William Herschel in 1805. Then, in the 19th century, other astronomers measured the brightest asteroids in exactly the same way. The main disadvantage of this method is significant discrepancies in the results (for example, the maximum and minimum dimensions Ceres, which were obtained by astronomers, differed by 10 times).
Modern methods for determining the size of asteroids consist of polarimetry, thermal and transit radiometry, speckle interferometry, and the radar method.
One of the highest quality and simplest is the transit method. When an asteroid moves relative to the Earth, it can pass against the background of a separated star. This phenomenon is known as asteroid occultation of stars. By measuring the duration of the star's dimming and having data on the distance to the asteroid, one can accurately determine its size. Thanks to this method, it is possible to accurately calculate the size of large asteroids, like Pallas.
The polarimetry method itself consists in determining the size based on the brightness of the asteroid. The amount of sunlight that it reflects depends on the size of the asteroid. But in many ways, the brightness of the asteroid depends on the albedo of the asteroid, which is determined by the composition that makes up the surface of the asteroid. For example, due to its high albedo, the asteroid Vesta reflects four times as much light as Ceres and is considered the most visible asteroid, which can often be seen even with the naked eye.
However, the albedo itself is also very easy to determine. The lower the brightness of the asteroid, that is, the less it reflects in the visible range solar radiation, the more it absorbs it, respectively, after it heats up, it radiates it in the form of heat in the infrared range.
It can also be used to calculate the shape of an asteroid by registering the change in its brightness during rotation, and to determine the period of this rotation, as well as to identify the largest structures on the surface. In addition, results from infrared telescopes are used to determine dimensions through thermal radiometry.
Asteroids and their classification
At the core general classification asteroids are the characteristics of their orbits, as well as a description of the visible spectrum of sunlight that is reflected by their surface.
Asteroids are usually combined into groups and families based on the characteristics of their orbits. Most often, a group of asteroids is named after the very first asteroid discovered in a given orbit. Groups - comparatively free education, while the families are denser, formed in the past during the destruction of large asteroids as a result of collisions with other objects.
Spectral classes
Ben Zellner, David Morrison, Clark R. Champin in 1975 developed common system classification of asteroids, which was based on the albedo, color and spectral characteristics of the reflected sunlight. At the very beginning, this classification defined only 3 types of asteroids, namely:
Class C - carbon (most known asteroids).
Class S - silicate (about 17% of known asteroids).
Class M - metal.
This list as you study everything more asteroids has been expanded. The following classes have appeared:
Class A - have a high albedo and a reddish color in the visible part of the spectrum.
Class B - belong to class C asteroids, only they do not absorb waves below 0.5 microns, and their spectrum is slightly bluish. In general, the albedo is higher compared to other carbon asteroids.
Class D - have a low albedo and an even reddish spectrum.
Class E - the surface of these asteroids contains enstatite and is similar to achondrites.
Class F - similar to class B asteroids, but do not have traces of "water".
Class G - have a low albedo and an almost flat reflectance spectrum in the visible range, which indicates strong UV absorption.
Class P - just like D-class asteroids, they are distinguished by low albedo and a smooth reddish spectrum that does not have clear absorption lines.
Class Q - have wide and bright lines of pyroxene and olivine at a wavelength of 1 micron and features that indicate the presence of metal.
Class R - have a relatively high albedo and have a reddish reflection spectrum at a length of 0.7 microns.
Class T - characterized by a reddish spectrum and low albedo. The spectrum is similar to class D and P asteroids, but is intermediate in slope.
Class V - characterized by moderate bright and similar to the more general S-class, which are also more composed of silicates, stone and iron, but differ high content pyroxene.
Class J is a class of asteroids that were formed presumably from internal parts Vesta. Despite the fact that their spectra are close to those of class V asteroids, at a wavelength of 1 micron they are distinguished by strong absorption lines.
It should be borne in mind that the number of known asteroids that belong to a certain type does not necessarily correspond to reality. Many types are difficult to determine, the type of an asteroid can change with more detailed studies.
Asteroid size distribution
With the growth of the size of asteroids, their number noticeably decreased. Although this generally follows a power law, there are peaks at 5 and 100 kilometers where there are more asteroids than predicted by the logarithmic distribution.
How asteroids were formed
Scientists believe that in the asteroid belt, planetesimals evolved in exactly the same way as in other areas of the solar nebula until the planet Jupiter reached its current mass, after which, as a result of orbital resonances with Jupiter, 99% of the planetesimals were ejected from the belt. Modeling and jumps in spectral properties and rotational velocity distributions show that asteroids larger than 120 kilometers in diameter were formed by accretion during this early epoch, while smaller bodies are fragments from collisions between different asteroids after or during Jupiter's gravitational dissipation of the primordial belt . Vesti and Ceres acquired an overall size for gravitational differentiation, during which heavy metals plunged to the core, and a crust was formed from relatively rocky rocks. As for the Nice model, many Kuiper belt objects formed in the outer asteroid belt, at a distance of more than 2.6 astronomical units. And later, most of them were thrown out by the gravity of Jupiter, but those that survived may belong to class D asteroids, including Ceres.
Threat and danger from asteroids
Despite the fact that our planet is significantly larger than all asteroids, a collision with a body larger than 3 kilometers can cause the destruction of civilization. If the size is smaller, but more than 50 m in diameter, then it can lead to gigantic economic damage, including numerous victims.
The heavier and larger the asteroid, the more dangerous it is, respectively, but to identify it in this case much easier. At the moment, the most dangerous is the asteroid Apophis, whose diameter is about 300 meters, in a collision with it, an entire city can be destroyed. But, according to scientists, in general, it does not pose any threat to humanity when it collides with the Earth.
Asteroid 1998 QE2 approached the planet on June 1, 2013 at its closest distance (5.8 million km) in the last two hundred years.
Asteroids are also often referred to as small planets, because they are quite impressive in size. Previously, few people were interested in them, but ten years ago the planet was threatened with a collision with one of them. A space body called Apophis was rapidly approaching the Earth. Meeting with him would have killed more than a quarter of the population, but the re-calculation of the trajectory showed that he would pass by. The panic, although it turned out to be false, was remembered for a long time and since then much more attention has been paid to asteroids.
The largest asteroids and their movement can be tracked by tuning the telescope to the main asteroid belt. A significant outer space filled with these not the largest objects is located between Mars and Jupiter. It is worth considering that there are much more massive asteroids in the universe, because the total mass of those that are in our solar system is no more than 5% of the mass of the moon. Most of it is completely occupied by individual hulks, the largest of which was considered Ceres. It could be called the largest asteroid in the solar system, but scientists recently recognized Ceres as a dwarf planet, so the title of true giant passed to the next three - Vesta, Pallas and Hygiea.
Vesta, according to the research of scientists, is the most massive and overall asteroid. Pallas, which for a long time was considered larger, turned out to be a little smaller, and Hygiea is inferior to both of them. This celestial body was generally discovered later than even those that are half or even three times smaller than it in size, and this is due to the fact that Hygiea itself is very dim and it is extremely difficult to see it.
The diameter of Vesta is 526 kilometers, it is also considered the brightest asteroid of all, because it is visible even to the naked eye. That is why the giant celestial body was discovered in 1807 by the German astronomer Heinrich Olbers, and named after the Roman goddess of home comfort.
If it were not for the asymmetry of forms, Vesta could, according to all accepted rules, be attributed to dwarf planets. This is also accompanied by its composition, which was discovered only with the advent of the Hubble telescope. He helped to examine it in all its glory, demonstrating, in addition to rocks, a crater with a diameter of over 500 kilometers. No other cosmic body in the solar system has a funnel of this size. Scientists are still wondering how Vesta managed to stay intact, withstanding such a powerful blow, because the crater goes as far as 25 kilometers deep.
There is only one, yet unconfirmed theory that explains this cosmic phenomenon. It lies in the fact that, according to some astronomers, most of the asteroids that are assigned class V are in fact only fragments of one large comic body. It did not manage to survive the powerful collision in integrity and now it is extremely difficult to determine what sizes and shapes it was at the very beginning.
The science
Our quest for knowledge of the universe is still in its infancy, and we are constantly surprised by any new discoveries.
There are still many mysteries that we have to solve, even in our small corner of the universe called the solar system.
Here are some interesting facts about most high mountain, the largest asteroid, the largest object and other cr secrets of our solar system.
1. The highest mountain
Mount Olympus- the famous Martian mountain, in comparison with which Everest seems like a small hill. At height 21,900 meters, this volcanic mountain has long been considered the highest in the entire solar system.
Mount Olympus on Mars
However, a recently discovered peak located on Vesta, one of the largest asteroids in the solar system, overthrew Olympus from the first place. The height of the peak, named Rheasilvia, is 22 km. m, which is 100 meters higher than Olympus.
Since these measurements are not absolutely accurate, and the difference between these peaks is not so big, it cannot be said with certainty that one is higher than the other.
Rheasilvia on the asteroid Vesta
When the Dawn spacecraft studied Vesta in 2011, it discovered that Rheasilvia is the central mountain in a giant crater 505 km in diameter, almost as long as the entire asteroid.
2. The largest asteroid
Pallas considered the largest asteroid in the solar system, but under certain circumstances.
Comparison of large asteroids
To begin with, it is worth noting Ceres - the first asteroid discovered, and by far the largest. It contains almost a third of the total mass of the asteroid belt. That is, technically Ceres can be considered the largest asteroid, but its upgraded to dwarf planet status.
Besides asteroid Vesta actually heavier than Pallas, but the latter is larger in volume.
It is possible that Pallas will not hold the title of the largest asteroid for long, since according to the latest Hubble images, it is dynamic. protoplanet.
In other words, this is not just a giant ball of stone and ice, but it undergoes internal changes with the change of dark and light areas. Perhaps in the near future it will become a candidate for dwarf planets.
3. The largest impact crater
At the moment there are three candidates claiming the title of the largest impact crater, and they are all on Mars.
Hellas Plain on Mars
The first and smallest of the three candidates is Hellas plain, whose diameter is 2300 km. However, it is the only one we know to have formed as a result of the impact.
The second largest crater is much larger than the previous one and is called Utopia plain. However, most likely, both of them look tiny compared to the largest crater in our solar system.
Great Northern Plain on Mars (center)
Diameter Great Northern Plain is 8500 km, and it is almost three times the size of the plain of Utopia.
However, it remains to be confirmed that it is an impact crater. If so, it must have been the result of a very large impact, and its formation will help us learn more about the formation of Mars as a planet.
4. The most volcanically active body
Volcanic activity is not as common in the solar system as one might think. Although many space bodies, such as Mars and the Moon show signs of volcanic activity, while there are four other bodies in which it is also observed.
Volcanic activity on Jupiter's moon Io.
In addition to the Earth, there are three volcanic satellites in the solar system: Triton(satellite of Neptune) And about(moon of Jupiter), and Enceladus(Saturn's moon).
Of all of them Io is the most active. On satellite images, they counted about 150 volcanoes, and astronomers believe that their total number is about 400. It is surprising that there is any volcanic activity here at all, given its icy surface and distance from the Sun.
According to one of the theories explaining how a hot interior is preserved in such a cold place, Io's volcanic activity is caused by internal friction .
Volcano on Io
The moon is constantly deforming internally due to the outward thrust of Jupiter and the two large moons of Ganymede and Europa. The backlash creates internal tides that cause friction and generate heat to keep volcanoes active.
5. The largest object in the solar system
Sun, which represents 99 percent of the mass of the solar system, is its largest object. However, in 2007, for a short period, the comet became larger than the Sun.
Rather, we are talking about the comet's coma - a cloudy region that surrounds the comet and consists of ice and dust. Comet 17P/Holmes was discovered in 1892 and was named after the astronomer who discovered it - Edwin Holmes.
Comparison of Comet 17P/Holmes and the Sun
Since then, scientists have tried to trace her, despite losing her for nearly 60 years between 1906 and 1964.
Although it is not typical for a comet to experience bursts of brightness, on October 23, 2007, Comet Holmes suddenly increased its brightness to nearly half a million.
It was the strongest comet flare which was visible to the naked eye.
Over the next month, the comet continued to expand until it reached diameter 1.4 million kilometers, officially becoming larger than the Sun.
We still do not know why this outbreak occurred, and in the future it may surprise astronomers more than once.
6. The longest channel
In 1989, the Magelan spacecraft was launched to Venus, which carried out the largest mapping of its surface. Also in 1991, he discovered the longest known riverbed in our solar system.
It was named Baltis Valley, whose length was 6800 km. Subsequently, many similar channels were discovered on the surface of Venus, but none could compare with the Baltis Valley.
But what surprises astronomers the most is how these channels could have come about, given that Venus is known for its harsh environment.
superficial the pressure there is 90 times greater than the earth, and the temperature can reach 462 degrees Celsius.
According to some assumptions, these channels appeared due to molten lava after volcanic eruptions. These lava beds are unlike anything we have on Earth, although perhaps similar characteristics were on our planet billions of years ago.
7. The largest lava lake
As mentioned earlier, Jupiter's moon Io is one of the few bodies in the solar system that is still volcanically active, and quite strong. All molten lava must go somewhere, and often this leads to the formation of lava lakes.
Patera Loki on Jupiter's moon Io
One of them Patera Loki is the largest lava lake in the entire solar system.
Although something similar is observed on Earth, none of these lakes is active. The biggest - Nyiragongo volcano in the Democratic Republic of the Congo reaches about 700 meters in diameter.
Volcano Nyiragongo on Earth
However, there is evidence indicating that masaya volcano in Nicaragua in the past formed an even larger lava lake, reaching 1 km in diameter.
Masaya Volcano on Earth
All this allows you to look at Patera Loki from the outside, whose diameter was 200 km. Given that its total surface area is not directly proportional, since the lake has an unusual U-shape, it is very large.
The lake is almost twice as big Pateri Gish Bar- the second largest lava lake on Io with a diameter of 106 km.
8 Ancient Asteroids
Despite all the research that has been done, we still cannot say with 100 percent certainty how asteroids are formed.
There are currently two main theories: they formed like the planets(pieces of material collide with other pieces and get bigger and bigger), or they could be ancient planets between Mars and Jupiter, whose destruction led to the creation of the asteroid belt.
Our understanding of asteroid formation advanced in 2008 when researchers at the Mauna Kea Observatory in Hawaii discovered the oldest known asteroids in our solar system.
Asteroids whose age was 4.55 billion years, were older than any meteorites that fell to Earth, and close to the age of the solar system itself.
Their age was determined by analyzing the composition, and found that all three asteroids contain large amounts of aluminum and calcium, which is more than any other space rock ever found.
9 Longest Comet Tail
Comet Hyakutake or Big Comet 1996 known for the longest tail in history.
Hyakutake or Big Comet 1996
When Hyakutake flew by in 1996, it was closer than any comet as it approached Earth. The comet became very bright and was visible to the naked eye.
> The largest asteroids
Explore the largest asteroids in the rating of the solar system: the first place of Ceres, description and characteristics of objects, discovery, distance, orbit, mass.
List of largest asteroids
Giuseppe Piazzi discovered it in 1801, but at first it was considered the eighth planet. Then were not found and. This is the first asteroid ever found. Ceres still remains the largest asteroid today with its polar diameter of 909 km. This is the only asteroid that is considered a dwarf planet, although very, very small. Its shape suggests that its developed topography is similar to that of Earth. Ceres may have large reserves of water ice under the crust because its density is quite low.
It is possible that Ceres may have more water than all the reserves. fresh water on the ground. Ceres contains almost a third of the mass of the entire Asteroid Belt. Planetary astronomers generally believe that Ceres evolved like it did in the early days of the formation of the solar system, but stopped merging with other protoplanets like Earth did. Its orbit around is approximately 2.5468 astronomical units. It will take 4.6 years for it to make a complete revolution around the Sun.
Discovered after Ceres in 1807. It is the second largest and second largest asteroid. Her body has an elongated shape: 580 km by 460 km. The mass is about 9% of the total mass of the main belt asteroids. In the past billions of years, Vesta has suffered catastrophic collisions. They left a crater on her south pole, which is approximately 460 km across. About 1% of its total mass in space was ejected. The remaining fragments, which in total number about 235 pieces, together with Vesta itself form the Vesta group of asteroids. Some fragments are considered to be the source of meteorites. Many of them have found their way to Earth. Its eccentric orbit is between 2.151 and 2.572 astronomical units from the Sun. It will take 3.63 years for it to make a complete revolution around the Sun.
It was discovered in 1802. Its diameter, which varies from 580 to 500 km (average 544 km), makes it comparable in size to Vesta, but Pallas is significantly lighter - about 7% of the total mass of asteroids. Its eccentric orbit around the Sun ranges from 2.132 to 3.412 astronomical units. The object is significantly deviated from the main plane by almost 35°.
10 Hygeia
Discovered in 1849. It is the fourth largest among asteroids, its body also has an elongated shape: 530 x 407 x 370 km (average 431 km). The orbit is located at a distance of 2.77 to 3.507 astronomical units. Hygiea makes a complete revolution around the Sun every 5.56 years. This is the largest asteroid in the Hygiea family, as it makes up 90% of the entire family mass.
704 Interamnia
Interamnia measures approximately 350.3 by 303.6 km with an average diameter of 326 km. It makes up approximately 1.2% of the total mass of asteroids in the main belt. Its orbit is moderately eccentric and ranges from 2.601 to 3.522 astronomical units. Interamnia makes a complete revolution around the Sun every 5.36 years.
511 David
David is an elongated asteroid measuring 357 x 294 x 231 km. Its orbit is moderately eccentric and ranges from 2.58 to 3.754 astronomical units. 511 David makes a complete revolution around the Sun in 5.64 years. It is believed that there is a massive crater on its surface, the size of which is about 150 km in diameter.
87 Sylvia
Sylvia has a very low density and an elongated shape of approximately 384 x 262 x 232 km. Its orbit is moderately eccentric and ranges from 3.213 to 3.768 astronomical units. 87 Sylvia takes about 6.52 years to complete one revolution around the Sun. The asteroid has two small moons called Romulus and Remus. Romulus is about 18 km in diameter and is located at a distance of 1356 km from the asteroid, making a complete revolution every 87.59 hours. Remus is 7 km in diameter and is located at a distance of 706 km, making a complete revolution around the asteroid in 33.09 hours.
65 Cybele
The asteroid Cybele measures about 302 x 290 x 232 km. Its orbit is moderately eccentric and ranges from 3.073 to 3.794 astronomical units. 65 Cybele makes a full revolution around the Sun every 6.36 years.
15 Eunomia
Eunomia is an elongated asteroid measuring about 357 x 255 x 212 km. Its orbit is moderately eccentric and ranges from 2.149 to 33.138 astronomical units. Eunomia makes a complete revolution around the Sun every 4.3 years.
