Asteroids. Asteroids (Asteroid), Small Planets

Composite image (on scale) asteroids shot in high resolution. For 2011, these were, from a larger to a smaller: (4) Vesta, (21) Lutection, (253) Matilda, (243) Ida and its satellite Dactyl, (433) Eros, (951) Gaspra, (2867) Steins, (25143) Iokava

Asteroid (common until 2006 synonym - small planet) - relatively small heavenly body moving in orbit around. Asteroids are significantly inferior by weight and sizes, have wrong shape And do not have, although they can be.

Definitions

The comparative dimensions of the asteroid (4) of Vesta, the dwarf planet of Ceres and the Moon. Resolution 20 km on pixel

The term asteroid (from DR. Greek. Ἀστεροειδής - "such a star", from ἀστήρ - "star" and εἶδος - "appearance, appearance, quality") was invented by composer Charles Burney and was introduced by William Gershel based on the fact that these objects with Observation in looked like points - unlike planets, which when observing the telescope looks with discs. The exact definition of the term "asteroid" is still not installed. Until 2006, asteroids were also called small planets.

The main parameter for which classification is performed is the body size. Asteroids are the bodies with a diameter of more than 30 m, smaller bodies are called.

In 2006, the International Astronomical Union was carried away by most asteroids to.

Asteroids in the Solar System

The main belt of asteroids ( white color) and Trojan asteroids of Jupiter (green color)

At the moment, hundreds of thousands of asteroids were detected in the solar system. As of January 11, 2015, there were 670,474 objects in the database, of which the orbits were defined for 422 636 and the official number was assigned, more than 19,000 of them were officially approved names. It is assumed that in a solar system can be from 1.1 to 1.9 million facilities having more than 1 km sizes. Most asteroids known at the moment are focused within the limits located between orbits and.

The largest asteroid in the solar system was considered having a size of approximately 975 × 909 km, however, from August 24, 2006, it received status. The other two largest asteroids (2) pallades and have a diameter of ~ 500 km. (4) Vesta is the only object of the belt of asteroids that can be observed non-equipped eye. Asteroids moving in other orbits can also be observed during the passage near (for example, (99942) Apophis).

The total mass of all the main belt asteroids is estimated at 3.0-3.6 · 10 21 kg, which is only about 4% of the mass. Ceres Mass - 9.5 · 10 20 kg, that is, about 32% of the total, and together with the three largest asteroids (4) of Vesta (9%), (2) pallades (7%), (10) gigia (3% ) - 51%, that is, the absolute majority of asteroids are insignificant in astronomical measurement mass.

Study asteroids

The study of asteroids began after discovery in 1781 by William Gershlem Planet. Its average heliocentric distance was relevant to the rule of Tizius - Bode.

IN late XVIII century Franz Ksaver organized a group of 24 astronomers. Since 1789, this group was engaged in the search for the planet, which, according to Titsius-Bode rule, was to be at a distance of about 2.8 astronomical units from the Sun - between the orbits of Mars and Jupiter. The task was to describe the coordinates of all stars in the field of zodiac constellations at a certain point. In the subsequent nights, the coordinates were checked, and objects were distinguished that shifted to a greater distance. The estimated displacement of the desired planet should have been about 30 angular seconds per hour, which should have been easily noticed.

Ironically, the first asteroid, cerer was found to the Italian Piazzi, who did not participate in this project, by chance, in 1801, on the first night century. Three others - (2) Pallada, (3) Juno and (4) Vesta were found in the next few years - the last, Vesta, in 1807. After 8 years of fruitless search, most astronomers decided that there is nothing else there, and stopped research.

However, Karl Ludwig Henke showed perseverance, and in 1830 resumed the search for new asteroids. Fifteen years later, he discovered an astray, the first new asteroid for 38 years. He also discovered Gebu less than two years. After that, other astronomers joined the search, and further was found at least one new asteroid per year (with the exception of 1945).

In 1891, Max Wolf first used the astrophotography method to search asteroids, in which there were short light lines in photographs with a long period of exposure of the asteroids. This method significantly accelerated the detection of new asteroids compared to previously used visual observation methods: Max Wolf alone found 248 asteroids, starting with (323) Bracia, whereas a little more than 300 was found before it was found, 385 thousand asteroids have The official number, and 18 thousand of them - also the name.

In 2010, two independent groups of astronomers from the USA, Spain and Brazil stated that at the same time discovered the water ice on the surface of one of the largest asteroids of the main belt - themis. This discovery makes it possible to understand the origin of water on Earth. At the beginning of its existence, the earth was too hot to keep a sufficient amount of water. This substance was supposed to arrive later. It was assumed that the water on the ground could be made by comets, but the isotopic composition of earthly water and water in comets does not coincide. Therefore, it can be assumed that the water to the ground was listed in its collision with asteroids. The researchers also discovered complex hydrocarbons on the femide, including molecules - life predecessors.

Naming asteroids

First, asteroids gave the names of the heroes of Roman and greek mythology, Later, the openers received the right to call them anyhow - for example, by their name. Initially, asteroids were predominantly female names, male names received only asteroids having unusual orbits (for example, Icar, approaching the sun closer). Later and this rule stopped observed.

Not any asteroid may receive a name, but only one orbit of which is more or less reliably calculated. There were cases when the asteroid received a name after decades after the opening. As long as the orbit is calculated, the asteroid is given a temporary designation, reflecting the date of its discovery, for example, 1950 DA. The numbers denote the year, the first letter - the number of the crescent in the year, in which the asteroid was opened (in the example given the second half of February). The second letter denotes the sequence number of the asteroid in the specified crescent, in our example asteroid was opened first. Since Crescents 24, and english letters - 26, the designation does not use two letters: i (due to the similarity with unit) and Z. If the number of asteroids open for the crescent will exceed 24, return to the beginning of the alphabet, attributing the second letter 2, with the next time return - 3, etc.

After receiving the name, the official naming of the asteroid consists of numbers ( ordinal number) and the names - (1) of the Cerecher, (8) Flora, etc.

Definition of the form and size of the asteroid

Asteroid (951) Gaspra. One of the first images of the asteroid obtained from the spacecraft. Transmitted by the Space Protection "Galileo" during his span by Gaspra in 1991 (colors strengthened)

The first attempts to measure the diameters of asteroids using the method of direct measurement of visible discs using a native micrometer was taken by William Herschel in 1802 and Johann Schreter in 1805. After them in the XIX century in the XIX century, the most vivid asteroids were measured by other astronomers. The main disadvantage of this method was significant differences in the results (for example, the minimum and maximum dimensions Ceres received by different scientists differed ten times).

Modern methods for determining asteroid sizes include polarimetry methods, radar, speckle-interferometry, transit and thermal radiometry.

One of the simplest and qualitative is the transit method. During the way the asteroid relative to the Earth, it sometimes passes against the background of a remote star, this phenomenon is called stars coverage asteroid. Having measured the duration of a reduction in the brightness of this star and knowing the distance to the asteroid, it is possible to determine the size to determine it. This method allows to accurately determine the size of large asteroids, like Pallas.

The polarimetry method is to determine the size based on the brightness of the asteroid. The more asteroid, the more sunlight He reflects. However, the brightness of the asteroid strongly depends on the albedo of the surface of the asteroid, which in turn is determined by the composition of the components of its breeds. For example, an asteroid of Vesta due to a high albedo of its surface reflects 4 times more of the light than Ceres and is the most noticeable asteroid in the sky, which can sometimes be observed by the naked eye.

However, the albedo itself can also be defined quite easily. The fact is that the smaller the brightness of the asteroid, that is, the less he reflects solar radiation In the visible range, the more it absorbs it and, heating, emits it as heat in the infrared range.

The polarimetry method can also be used to determine the form of an asteroid, by registering the change in its gloss in the process of rotation and to determine the period of this rotation, as well as to detect large structures on the surface. In addition, the results obtained by infrared telescopes are used to determine the size of thermal radiometry.

Classification of asteroids

The general classification of asteroids is based on the characteristics of their orbits and the description of the visible spectrum of sunlight, reflected by their surface.

Groups of orbits and families

Asteroids are combined into groups and families based on the characteristics of their orbits. Usually the group is called by the name of the first asteroid, which was discovered in this orbit. Groups are relatively free education, while families are denser formed in the past in the destruction of major asteroids from collisions with other objects.

Spectral classes

In 1975, Clark R. Chapman (Clark R. Chapman), David Morrison (David Morrison) and Ben Cellner (Ben Zellner) developed a system of classification of asteroids based on color indicators, albedo and characteristics of the spectrum of reflected sunlight. Initially, this classification defined only three types of asteroids:

Class C - carbon, 75% of famous asteroids.
Class S - silicate, 17% of famous asteroids.
Class M - metal, most others.

This list was later expanded and the number of types continues to grow as more and more asteroids are studied in detail:

Class A is characterized by a sufficiently high albedo (between 0.17 and 0.35) and a reddish color in the visible part of the spectrum.
Class B - in general refer to class C asteroids, but almost do not absorb the waves below 0.5 μm, and their spectrum is slightly bluish. Albedo is generally higher than that of other carbon asteroids.
Class D - characterized by a very low albedo (0.02-0.05) and an even reddish spectrum without clear absorption lines.
Class E - The surface of these asteroids contains in its composition such a mineral as an enstatient and may be similar to the ahondritis.
Class F - generally similar to class B asteroids, but without traces of "water."
Class G is characterized by a low albedo and almost flat (and colorless) in the visible range of the reflection spectrum, which indicates a strong ultraviolet absorption.
Class P - as well as class D asteroids, are characterized by a rather low albedo, (0.02-0.07) and an even reddish spectrum without clear absorption lines.
Class Q - at a wavelength of 1 μm in the spectrum of these asteroids there are bright and wide lines of olivine and pyroxen and, moreover, features indicating the presence of metal.
The class R is characterized by a relatively high albedo and a reddated reflection spectrum at a length of 0.7 microns.
Class T is characterized by a low albedo and a reddish spectrum (with moderate absorption at a wavelength of 0.85 μm), which is similar to the spectrum of asteroids of P- and D-classes, but by the inclination occupying an intermediate position.
Class V - asteroids of this class are moderately bright and pretty close to a more general class, which also mainly consist of stone, silicates and iron (chondrites), but differ s more high content Pyroxen.
Class J is a class of asteroids formed, presumably, from the inner parts of Vesta. Their spectra are close to the spectra of class asteroids V, but they are distinguished by particularly strong absorption lines at a wavelength of 1 μm.

It should be borne in mind that the number of known asteroids attributed to any type is not necessarily true. Some types are quite complex to determine, and the type of a certain asteroid can be changed with more thorough studies.

Problems of spectral classification

Initially, the spectral classification was based on three types of material constituting asteroids:

Class C - carbon (carbonates).
Class S - silicon (silicates).
Class M - metal.

However, there are doubts that such a classification uniquely determines the composition of the asteroid. While the different spectral class of asteroids indicates their different composition, there is no evidence that the asteroids of one spectral class consist of the same materials. As a result, scientists did not adopt a new system, and the implementation of the spectral classification stopped.

Distribution in size

The number of asteroids is noticeably reduced with the growth of their size. Although this is generally consistent with the power law, there are peaks at 5 km and 100 km, where more asteroids, than expected in accordance with the logarithmic distribution.

The formation of asteroids

In July 2015, he was reported to open the chamber of the Decam Telescope named after Victor Blanco of the 11th and 12th Trojan Neptune - 2014 QO441 and 2014 QP441. Thus, the number of Trojans at the Point of L4 Neptune increased to 9. Also, 20 other objects were discovered by this review, which received the center of small planets, including 2013 RF98, which possesses one of the largest periods of circulation.

The objects of this group are given the names of the centaurs of antique mythology.

The first open centaur was Chiron (1977). When it approaches the perihelion, it has a comet comet, so Hiron is considered to be classified simultaneously and comet (95p / chiron), and asteroid (2060 chiron), although it is significantly more typical comet.



Asteroids are relatively small celestial bodies moving in orbit around the sun. They are significantly inferior in size and mass by planets, have an irregular shape and have no atmosphere.

In this section of the site, everyone can learn a lot interesting facts About asteroids. Perhaps some of you are already familiar, others will be new for you. Asteroids are an interesting spectrum of space, and we suggest you familiarize yourself with them as much as possible.

The term "asteroid" was first invented by the famous composer Charles Bernie and was used by William Herscheme based on the fact that these objects when viewing in a telescope look like points of stars, while the planets look disks.

Still no accurate definition The term "asteroid". Asteroids until 2006 was customary with small planets.

The main parameter in which they are classified is the body size. Asteroids include bodies with a diameter of more than 30 m, and bodies having a smaller size are called meteorites.

In 2006, the International Astronomical Union in 2006, in 2006, made the majority of asteroids to the small bodies of our solar system.

To date, hundreds of thousands of asteroids have been identified in the solar system. On January 11, 2015, 670474 facilities are listed in the database, from among those in 422636 orbits are identified, they have the official number, more than 19 thousand of them were official names. According to scientists, in the solar system can be from 1.1 to 1.9 million objects, more than 1 km size. Most asteroids known at the moment are within the belt of asteroids located between the orbits of Jupiter and Mars.

The largest asteroid in the solar system - Ceres, having dimensions of approximately 975x909 km, but from August 24, 2006 it was given to the number of dwarf planets. The remaining two large asteroids (4) of Vesta and (2) pallades have a diameter of about 500 km. Moreover, the (4) Vesta is the only object of the belt of asteroids, which is visible to the naked eye. All asteroids that move through other orbits can be traced during the passage near our planet.

Concerning total weight All asteroids of the main belt, it is estimated at 3.0 - 3.6,021 kg, which is approximately 4% of the weight of the moon. However, the mass of Ceres accounts for about 32% of the entire mass (9.5 1020 kg), and together with three other major asteroids - (10) gigae, (2) pallades, (4) Vesta - 51%, that is, most asteroids differ An insignificant mass on astronomical standards.

Study asteroids

After William Herschel opened Uranian Planet in 1781, the first openings of asteroids began. The average heliocentric distance asteroids corresponds to the Tsyius Bode rule.

Franz Ksaver at the end of the 18th century created a group of twenty-four astronomers. Starting from 1789 this group Specialized in search of the planet, which, according to the rule of Tizius-Bode, should be located at a distance of about 2.8 astronomical units (A.E.) from the Sun, namely between the orbits of Jupiter and Mars. The main task was to describe the coordinates of stars located in the field of zodiac constellations at a particular point. The coordinates were checked in the subsequent nights, objects shifted over long distances. According to their assumption, the displacement of the desired planet should be about thirty angular seconds per hour, which would be very noticeable.

The first asteroid, cerer, was revealed by an Italian piano, which did not participate in this project, completely by chance, on the first night century - 1801. Three other - (2) pallades, (4) Vesta and (3) Juno were discovered in the next few years. The very last (in 1807) was Vesta. After another eight years of meaningless searches, many astronomers decided that there was nothing more to look for, and abandoned any attempts.

But Carl Ludwig Henke revealed perseverance and in 1830 again began to search for new asteroids. After 15 years, he discovered an astray, which was the first asteroid for 38 years. And after 2 years I discovered Gebu. After that, other astronomers were connected to work, and then at least one new asteroid per year was found (except 1945).

The method of astrophotography for the search for asteroids was first used Max Wolf in 1891, according to which the asteroids were left in the photo with a long period of exposure of the asteroids. This method significantly accelerated the identification of new asteroids compared to visual observation methods used earlier. Alone, Max Wolf was able to detect 248 asteroids, whereas a few managed to find more than 300. Nowadays, 385,000 asteroids have the official number, and 18,000 of them are also the name.

Five years ago, two independent groups of astronomers from Brazil, Spain and the USA said that at the same time revealed water ice on the benemis surface, one of the largest asteroids. Their discovery made it possible to learn the origin of the water on our planet. At the beginning of its existence, it was too hot, unable to keep a large number of water. This substance appeared later. Scientists suggested that the water on the ground was listed comets, but only isotopic composition Water in comets and earthly water do not coincide. Therefore, it can be assumed that she fell on the ground in its collision with asteroids. At the same time, scientists have discovered complex hydrocarbons on the femide, incl. Molecules - predecessors of life.

Name asteroids

Initially, asteroids were given the names of the heroes of Greek and Roman mythology, later the openers could call them how they would like, up to their own behalf. First, the asteroids almost always gave female names, the men also received only those asteroids who had unusual orbits. Over time this rule Observe stopped.

It is worth noting that not any asteroid can get a name, but only one orbit of which is reliably calculated. Often there have been cases when the asteroid was called many years after the opening. While the orbit was not calculated, the asteroid was given only a temporary designation that displays the date of its discovery, for example, 1950 DA. The first letter means the number of the crescent a year (in the example, as you can see, this is the second half of February), respectively, the second indicates its sequence number in the specified crescent (as you can see, this asteroid was opened first). Figures, as easy to guess, designate a year. Since the English letters 26, and the Crescents 24, two letters were never used in the designation: Z and I. In the event that the number of asteroids opened for a crescent will be more than 24, scientists returned to the beginning of the alphabet, namely, prescribing the second letter - 2, respectively, the next return - 3, etc.

The name of the asteroid after receiving the name consists of a sequence number (number) and the names - (8) Flora, (1) of Cerecher, etc.

Determination of the size and shape of asteroids

The first attempts to measure the diameters of asteroids, applying the method of direct measurement of visible discs by means of a native micrometer, was taken by Johann Schretcher and William Herschel in 1805. Then in the 19th century, other astronomers in exactly the same method were measured by the brightest asteroids. The main disadvantage of this method is a significant difference in the results (for example, the maximum and minimum sizes of Ceres, which were obtained by astronomers, differed 10 times).

Modern methods for determining the size of asteroids consist of methods of polarimetry, thermal and transit radiometry, speckle interferometry, radar method.

One of the highest quality and simple - transit method. When the asteroid movement relative to the Earth, it can pass on the background of the separated star. This phenomenon was called "coating asteroids". Having measured the duration of a reduction in the brightness of the star and having data on the distance to the asteroid, you can accurately determine its size. Thanks to this method, you can accurately calculate the size of large asteroids, by the type of Pallad.

The polarimetry method itself consists in determining the size of the brightness of the asteroid. The amount of sunlight, which it reflect depends on the asteroid value. But in many respects, the brightness of the asteroid depends on the albedo of the asteroid, which is determined by the composition from which the surface of the asteroid consists. For example, due to the high albedo, the asteroid Vesta reflects four times more of the world compared to the cherry and is considered the most noticeable asteroid, which can often be seen even with the naked eye.

However, the albedo itself is also very easily determined. The smaller the brightness of the asteroid, that is, it is less reflecting in the visible range of solar radiation, that, accordingly, it absorbs it, after it is heated, radiates it in the form of heat in the infrared range.

It can also be used to calculate the form of the asteroid by registering the change of its shine during rotation and to determine the period of this rotation, as well as to identify the largest structures on the surface. In addition, the results obtained by infrared telescopes are used to determine the size by means of thermal radiometry.

Asteroids and their classification

The general classification of asteroids is the characteristics of their orbits, as well as a description of the visible spectrum of sunlight, which is reflected by their surface.

Asteroids are made to unite in groups and families, relying on the characteristics of their orbits. Most often, the asteroid group is called by the very first asteroid detected in this orbit. Groups are relatively free education, while families are more dense, formed in the past when the larger asteroids are destroyed as a result of a collision with other objects.

Spectral classes

Ben Cherler, David Morrison, Clark R. Campen in 1975 developed general System The classification of asteroids, which relied on the albedo indicators, the colors and characteristics of the spectrum of reflected sunlight. At the very beginning, this classification was determined exclusively 3 types of asteroids, namely:

Class C - carbon (most of the famous asteroids).

Class S - silicate (about 17% of famous asteroids).

Class M - metal.

This list as an increasing number of asteroids has been expanded. The following classes appeared:

Class A - differ in high albedto and reddish color in the visible part of the spectrum.

Class B - belong to the class C asteroids, only they do not absorb the waves below 0.5 microns, and their spectrum is a bit blue. In general, the albedo is higher compared to other carbon asteroids.

Class D - have a low albedo and a smooth reddish spectrum.

Class E - the surface of these asteroids contains an enstatate in its composition and has similarities with ahondritis.

Class F - similar to asteroids b class, but do not have traces of "water".

Class G - have a low albedo and almost flat spectrum of reflection in the visible range, which indicates a strong UV absorption.

Class P - just like the asteroids of the D-class, are distinguished by a low albedo and a flat reddish spectrum that does not have clear lines Absorption.

Class Q - have wide and bright pyroxen lines and olivine at the wavelength of 1 microns and features that spelling the presence of metal.

Class R - differ in relatively high albedo and at a length of 0.7 microns have a reddish spectrum of reflection.

Class T - differ in a reddish spectrum and low albedo. The spectrum is similar to asteroids D and P classes, but occupies an intermediate position by the slope.

Class V is characterized by moderate bright and similar to a more general s-class, which also consist of a greater degree of silicates, stone and iron, but differ in high pyroxen content.

Class J - the class of asteroids, which were formed presumably from the inner parts of Vesta. Despite the fact that their spectra are close to the spectra of class V asteroids, on the wavelength of 1 microns they are distinguished by strong absorption lines.

It should be borne in mind that the number of known asteroids, which relate to a certain type, optionally corresponds to reality. Many types are complex to determine, the type of some asteroid may vary with more detailed studies.

Distribution of asteroids in size

With the growth of the size of asteroids, their number was noticeably decreased. Despite the fact that in general it corresponds to a power law, there are peaks at 5 and 100 kilometers, where more asteroids than predicted in accordance with the logarithmic distribution.

As asteroids were formed

Scientists believe that the planetsimali asteroids were evolved in the same way as in other areas of solar nebula before the planet Jupiter reached its current mass, after which, as a result of orbital resonances with Jupiter from a belt, 99% of the planezimals were thrown. Simulation and jumps of spectral properties and distributions of rotational speeds show that asteroids having a diameter of more than 120 kilometers were formed as a result of accretion in this early era, while smaller bodies are fragments from collisions between different asteroids after or during the dispersion by gravitation of Jupiter of the initial belt . Lead and ceres purchased overall size for gravitational differentiation, during which heavy metals Immersed to the kernel, and from relatively rocky rocks the bark was formed. As for the model of Nice, the set of objects of the Koiper belt were formed in the outer belt of asteroids, at a distance of more than 2.6 astronomical units. Moreover, most of them were thrown out by the gravity of Jupiter, but those that remained may relate to class D asteroids, including Ceres.

Threat and danger from asteroids

Despite the fact that our planet is substantially greater than all asteroids, a collision with a body having a size of more than 3 kilometers may cause the destruction of civilization. If the size is smaller, but more than 50 m in diameter, then it can lead to giant economic damage, including numerous sacrifices.

The harder and more asteroid, the, respectively, it is a great danger, but also to reveal it in this case much easier. At the moment, the most dangerous is the asteroid of Apophis, the diameter of which is about 300 meters, when a collision can be destroyed as a whole city. But, according to scientists, in general, he does not carry any threat to humanity in a collision with the Earth.

The 1998 QE2 asteroid approached the planet on June 1, 2013 at the closest distance (5.8 million km) over the past two hundred years.

Ranat for a couple of sleepless nights the story about how they was called and called asteroids. IMHO, interesting story Both in terms of the development of astronomy, and in terms of demonstration of the fact that even in such an accurate and noble science is not smoothly.

To begin with, I remind basic things. Asteroids (the term introduced William Herschel in 1802) or small planets are called small bodies of the solar system (not large enough to consider the planet, but more than thirty meters, smaller objects are called meteoroids), applying around the Sun and are not comets (for comets are characterized by gas-forming activity When approaching the Sun; In this case, individual asteroids are, in fact, "degenerating", "extinct" comets).

The first open asteroid was Cercher (it was opened on January 1, 1801). At first, it was considered a full-fledged planet (occupying the position between Mars and Jupiter), then it became clear that it was only one of the representatives of the large group of heavenly bodies, and in 2006 it was reclassified as a dwarf planet. Subsequent asteroids were opened in 1802 (Pallada), 1804 (Juno) and 1807 (Vesta) for years. Then there was a break until 1845 (as Astrey was opened), and since 1847, asteroids began to open several per year. By the beginning of the 20th century, more than four and a half hundred asteroids were already known; It is clear that in the future the frequency of their discoveries constantly increased, at the end of the XX century this growth became explosive. As of July 9, 2017, 734274 asteroids are known, of which 496815 have permanent numbers (that is, their orbit is considered reliably calculated), while only 21009 asteroids have their own names (infa from the center of small planets).

The image is taken from here: https://commons.wikimedia.org/wiki/file:minor_planet_count.svg

It is clear that the designation and naming of asteroids is a rather serious problem (since the number of asteroids is so great). I will try to tell about solutions to this problem. The main part of the text is based on the book. Schmadel, Lutz D. Dictionary of Minor Planet Names. - Fifth Revised and Enlarged Edition. - B., Heidelberg, N. Y.: Springer, 2003. - P. 298. - ISBN 3-540-00238-3 (not a translation, and free retelling), plus information was attracted from Wikipedia. Who is interested - read on.

Formal symbols asteroids

Until the middle of the XIX century, the nomenclature problem in relation to asteroids did not exist. Ceres, Pallada, Junon and Vesta (first open asteroids) were simply mentioned by name. The problem arose only about the 1850s due to the significant increase in the number of open asteroids. At first it seemed possible to just give each asteroid given name And create a separate astronomical symbol for each of them (that is, to act just as previously received with large planets). However, the practice of awarding characters quickly showed its inconsistency. The use of these symbols turned out to be both difficult from the point of view of book publishing equipment and completely impractical from the point of view of the load on the memory (to mention all these symbols, given the further growth of their number, it seemed impossible). Most likely, the last astronomer who assigned a separate symbol asteroid (namely asteroid (32) Fides), was Carl Theodore Robert Luther (Luther, 1855).

Instead of using the characters, a system of sequence numbers was introduced. For the first time, a similar idea (with the place of the sequence number of the asteroid in a circle) expressed Johann Franz Enke (Enke, 1851) on the pages "Berliner Astronomisches Jahrbuch" (hereinafter - Baj.). First practical use This system belongs to the American Astronoma James Ferguson (Ferguson, 1852), which marked the psyche as ⑯ Psyche (The asteroid Psyche was opened in 1852; Currently, the sequence number of the asteroid is placed in parentheses - (16) Psyche). The sequence number was awarded the editor of the magazine "Astronomische Nachrichten" (hereinafter - AN.) Accordingly, the date of the first publication on the opening of a new asteroid, which soon led to unpleasant contradictions: so, in early October 1857, Ferguson opened Asteroid Virginia, who was assigned to the sequence number 50, while the asteroid, open Goldshmidt in September of the same year (Melta) The sequence number 56 was assigned. The astronomical community concluded that the appointment of the Astroides of his own name could and move back for a certain period, while the tradition of awarding ordinal numbers strictly in accordance with the chronology of discoveries should be observed strictly.

The questions of the names and awarding of the ordinal numbers were additionally complicated by the fact that it was difficult to judge who exactly to the discoverer and who exactly had the right to give the name to the new asteroid. Wolf Rudolph (Wolf, 1859) belongs to the following remark: "The opening of uranium cannot be attributed to the Flemstad, the opening of Neptune cannot be attributed to Loland, just as the opening of the asteroid-56 cannot be attributed to Goldshmidt: the planet's discoverer is not the one who first saw her or Purpose, and the one who first recognized the new heavenly object in it. " Cases when the first observer did not realize the nature of the observed object, and the main role in the opening belonged to the person for the first time to the orbit of the new body, was already frequent. Issues related to these details remain relevant to this day.

Picture of Ceres in natural color made spacecraft "Dawn" May 4, 2015.

The rapid increase in the number of discoveries of new asteroids made the editorial board of BAJ and AN magazines award sequence numbers as soon as possible, respectively, opening dates. Despite the fact that the idea of \u200b\u200bstrict accordance between the ordinal numbers and chronology of discoveries did not cause objections, the rapid increase in the number of newly open asteroids soon gave rise to new difficulties. A significant number of new asteroids was observed only sporadically, without confident calculation and confirmation of their orbits - how did they follow with them? Avoid any sequence numbers or not? Adalbert Kruger (Kruger, 1892) suggested the following system: "From now on, the editor An will award each new planet [implied asteroids] in the following designation of the following type: 18xx a, b, c ... according to the date of registration [Opening Messages] in the Central Bureau of Astronomical Telegrams. The final serial number will be awarded only later by the editor of Baj. This will eliminate the giving the ordinal numbers of those planets [t. e., asteroids], whose orbital elements cannot be calculated due to lack of data. " That is, the first asteroid, allegedly open in 1893, received a permanent designation 1893 A, the second one open in the same year - 1893 B, and so on. However, after a year, in 1893, it became clear that only the capital letters would not be enough, in connection with which it was decided to expand this system by doubling the letters: so, the asteroid 1893 AA was due to the Asteroid 1893 Z, after it - 1893 AB, and so on. The system was accepted into use, but it should be noted that during the First World War, individual "unofficial" systems were also used; In particular, astronomers of the Simesis Observatory (this is the one that in our Crimea), who worked for some time without reliable communication with the rest astronomical worldThey were forced to introduce their own system of vcr-numeration of new asteroids.

In 1924 (taking into account the increasing number of newly open asteroids) was proposed new system During the opening year, there is a year of discoveries first, and after the gap Latin letter, denoting the opening crescent (A - for the first half of January, B - for the second half of January, C - for the first half of February, and so on, excluding the letter I, since it can confuse with one); It joins another Latin letter, denoting the discovery of the discovery in the corresponding crescent (again, excluding the letter I). So, for example, the designation 1926 AD means that the asteroid was opened by the fourth in the first half of January 1926, and the designation 1927 DG is that the asteroid was opened by the seventh in the second half of February 1927. Almost immediately (Kopff, 1924) this system was further expanded to the current state (" on that incredible case (SIC !!!) - As August Copoff himself wrote - if more than 25 asteroids are open for the crescent"): Now, if more than 25 small planets are open for the crescent (26 letters of the Latin alphabet minus one, i is not used), then a digital index is added to the designation, which shows how many times the alphabetic sequence in the second position was used (thus the number of discoveries In this half of the month, it is determined by multiplying the index by 25 plus the sequence number of the second letter in the designation of the asteroid). That is, the twenty-fifth asteroid, open in the first half of January 1950, will receive the designation of 1950 AZ, while the next (26th) will receive the designation 1950 AA 1, 27th - 1950 AB 1, 51st - 1950 AA 2 and etc. Check out your intelligence and answer the question: in which crescent and how in order in this crescent, the celestial body 2003 VB 12 was opened? I will give the right answer at the very end of the record :).

Since 1952, according to the proposal of American astronomer Paul Hergeta, the permanent (final) ordinal numbers began to be awarded only in the case of a number of conditions (Herget, 1952). The orbital parameters of these objects were to be calculated:
a) on the basis of observations in at least two confrontations (this requirement can be excluded if the perihelial distance in the observed body is less than 1.67 a. e.);
b) taking into account the perturbations;
c) satisfying all the Donna observations.

After time, the requirements for the assignment of a permanent sequence number were even more tightened: with the exception of objects with rather unusual orbits or mighty to get closer to the land for assigning a permanent number it was necessary to carefully observe the object in at least three confrontations. In 1991, American astronomer Brian Marsden (who was then the head of the center of small planets - the central to today, the organization engaged in the systematization of data on new open bodies of the Solar System) put forward the requirement even about four or more observations in the confrontation for assigning a permanent order number (excluding objects convergent With earth or constantly observed).

Development of traditions on the name of asteroids

The names of the first asteroids (Ceres, Pallada, Juno and Vesta) followed the classical tradition, in which heavenly bodies were called the names of ancient (Greek and Roman) gods or mythological characters. At first, it seemed that this tradition would be unshakable, but the name had already twelve asteroid Victoria (opened in 1850; formally the name corresponded to the Roman goddess of victory, but the astronomical community had serious suspicions that the discoverer, Briton John Russell Heind, gave this name in The honor of Queen Victoria) gave rise to discussions about whether to call asteroids in honor of the existing rulers. One of the most active wards for exclusively "classic" names was the German astronomer Carl Theodore Robert Luther (Luther, 1861), who postulated the following: "Since we consider it necessary to give our own names to the stars, comets, satellites of Saturn and Uranus and even the mountains on the moon, It seems reasonable to prefer the name from classical mythology. Non-class names are unreasonable from the point of view of long-term use, it is better to use only numbering. "

Such a dogmatic approach immediately ran into harsh criticism. Karl Augusta Steingeil (Steinheil, 1861) Polemized with Luther: "What is the advantage of using only classic names? Really new planets should only remind us that we once visited a classic school? Is Astronomy really obliged philology to remember all these names? "

Picture of Vesti (the brightest of asteroids), performed by the "DAWN" spacecraft in 2012.

Despite the fact that Luther's categorical approach met a lot of objections, the tendency to assign the names from Greco-Roman mythology with newly open asteroids for quite a long time. Of course, there were a lot of exceptions: asteroid can serve as the most striking example (45) Eugene, Opened in 1857 and named after the French Empress Evgenia de Montiho, Napoleon III spouse (the first case, as an asteroid was assigned a name in honor of another person). Asteroid (51) Nemause (Opened in 1858) was named the Latin name of the French city of him. Asteroid (77) Frygga (opened in 1862) was named after Frigg, his wife Odin and the Supreme Goddess in german-Scandinavian Mythology. Asteroid (89) Julia (Opened in 1866) was named after the Christian Holy Julia Corsican, who died in the V century. Asteroid (88) fesby It was named after the heroine of the Babylonian Legendary (Pirs and Fisba - the Babylonian analogue of Romeo and Juliet). Both, etc. Nevertheless, we note that even the names that did not have a direct relationship to Greco-Roman mythology, they still translated into the form of a female genus according to tradition.

The struggle for exclusively "classic" names, however, continued. The same Luther in 1878 declared: "The current names of asteroids have become more than a diverse mixture. It seems very advisable to return to old preferences, to classic mythological names. Any hints should be avoided - for the sake of honor of our science. " He ends Henry Bruns (Bruhns, 1878): " Better decision Any names causing associations with living people and current events seems to be avoided. Only classic names will receive universal recognition. "

When the number of open asteroids exceeded four hundred, to support the "mythological" tradition became even more difficult than earlier. Unofficial, but the rule-wide recognition, the rule in relation to the naming of new asteroids was only reduced to the requirement to use exclusively female names. Julius Bausinger (Bauschinger, 1899; He, by the way, was a consultant of the doctoral dissertation of Alfred Vegener, who later put forward the theory of the drift of the continents) into being the director of Astronomisches Rechen-Institut, even almost threatened: "There are reasons to ask for the discovers not to deviate from tradition to use women's names Since this rule was violated - insensitive - only once in relation to asteroid (433) Eros. The male names of asteroids will not be accepted by Baj. " Heinrich Kreitsa fully agreed with Baushinger (Kreutz, 1899), who was then the editor An, who said that male names would not be considered by the editors of AN. It should be clarified that asteroid (433) Erosworked in 1898 by Karl Witt, really became the first asteroid with a classic male name, but then it was "forgiven" for the fact that his orbit was extremely unusual for the then ideas: if the "classic asteroids" apply only between the orbits of Mars and Jupiter, That Eros became the first open body from the group of "near-earth asteroids", the perigels of his orbit lies inside the orbit of Mars.

Asteroid Eros (a series of photos performed by NEAR spacecraft in 2000 demonstrates its rotation).

The tradition of the name of asteroids is only women's names (even if female name It was created only artificially by adding endings. -a. or -ia.) It lasted for quite a long time - about the end of the Second World War (although it was repeatedly broken). For example, according to this tradition, asteroid 449 (opened in 1899 and called in honor of Hamburg) received a name Hamburg, asteroid 662 (opened in 1908 and called Newton's city from Massachusetts) received a name Newtonian, and asteroid 932, opened in 1920 and named after Herbert Hoover, got a name Guverly., etc., many examples. The final departure from this tradition was declared in the center of the center of small planets at number 837 (1952): "The tradition of giving women's endings to male names Already has many exceptions. From now on, the proposed names will not turn or modify if they have a male form. "

Current preferences Regarding the naming of asteroids (it is difficult to call them directly with rigid rules) were formulated in 1985. Now The following procedure works:
1. First, the newly open body gives a vpmentless alphanumeric designation (see above).
2. When the orbit of the new body is defined quite confidently (as a rule, this requires observation of the object in four or more confrontations), the center of small planets awards it a permanent number.
3. After the permanent sequence number is awarded, the discoverer is proposed to give the body its own name. The discoverer must accompany his name with a brief explanation of the reasons why he considers this name worthy of choice.
4. The proposed names are considered and approved by the Working Group of the International Astronomical Union on the Nomenclature of Small Tel.

The following formal requirements are presented to the proposed names (not always observed, but still extremely desirable):
1. The name should not consist of more than 16 letters.
2. It is very desirable that it consists of one word.
3. The word must be pronounced and make sense at least in some language (that is, just a random set of letters like Azzzxwfhu.Most likely, will be rejected).
4. The name should not be offensive or cause unpleasant associations.
5. The new name should not be too similar to the already available names of other solar system objects.
6. Pet's nicknames are not approved (although there were precedents when the asteroids received names in honor of the lover's pets).
7. Names of commercial type ( trade marks etc.) are not allowed.
8. Names based on policy names or related to any military actions are allowed to consider only if after the death of the character or events has passed 100 years.
9. Unlike comet, asteroids are not called automatically in honor of their discovers (however, often the discoverers called different asteroids in honor of each other). However, there is an exception: astold (96747) Cherbodasilva It was named after his discrepure, Lucy d'Escoffier Crespo da Silva, who ended up with him shortly after his discovery of 22 years.

For naming individual groups of asteroids (characterized by certain properties), more stringent traditions are still adhered. For example, the so-called Trojan asteroids (in resonance 1: 1 with Jupiter) receive names in honor of the heroes Trojan War; Transneptunional objects with stable and long-lived orbits receive mythological names, one way or another associated with the creation of the world, etc.

The name becomes official after its publication in the circular center of small planets. International Astronomical Soyuz Does not amend the name for money.

As of July 9, 2017, from 734274 well-known asteroids, the final numbers were assigned 496815 asteroids, while their own names are available only in 21009 of them (that is, only four percent of total asteroids with regular numbers). Most of the icons of asteroids consists of seven letters (information for 2003). The rule that the length of the name should not exceed 16 characters, was broken once in the case of an asteroid (4015) Wilson-Harrington.

Interesting Facts

The first asteroid with the name not related to antique mythology, became (20) Mass (open in 1852 and called greek name Marseille city).

The first asteroid called in honor of the living person became (45) Eugene (Opened in 1857 and named after Wife Napoleon III Evgenia de Montijo).

The first man, in honor of which an asteroid was named, became Alexander von Humboldt: In his honor, an asteroid was named (54) Alexander, Opened in 1858 (it can be seen that the asteroid named was made a female form; In addition, it was possible that the name was given in honor of Alexandra, the daughter of the mythological king Priama, but the intention of the discoverer was in the name of the asteroid in honor of Humboldt).

Although the names of domestic pets are now considered "forbidden", the precedents of this kind are still available. So, asteroids (482) Petrina and (483) Seppin Named in honor of the dogs (Peter and Sepp) of the discoverer M. F. Wulf (both asteroids were opened in 1902). The asteroid opened in 1971 was called (2309) Mr. Spock In honor of the Cot for the discoverer (the cat, in turn, received his nickname in honor of the character of the television series "Star Path").

Among the names of asteroids can be found and so unusual as (4321) Zero (named after the nickname of the American comedy actor Samuel Joel "Zero" Mosella), (6042) Cheshire Cat (named after the character "Alice in Wonderland"), (9007) James Bond (here played on hand the sequence number of the asteroid), (13579) Military (in original - AllODD., the sequence number of Astroide consists of often numbersgoing on in the increasing order) (24680) Complete (in original - Alleven.).

Photo of the Asteroid of Gaspra (named after the Crimean village), which became the first asteroid examined by the spacecraft (Galileo, 1991).

The names of asteroids are often adapted in separate national languages. Thus, the very first open asteroid (now considered a dwarf planet) we call Cercher, whereas many Western languages \u200b\u200bcall it Ceres, and the Greeks are also a demeter (Δήμητρα). Juno Greeks call the hero, Vesta - Gestius, etc., according to the analogies between Greek and Roman mythology. In Chinese, the classic names of asteroids end in the hieroglyph 星 (star, heavenly body), before which should be hieroglyph 神 (deity) or 女 (woman), and in front of him - the hieroglyph describing the most characteristic property of this deity. So, for example, ceres are referred to in Chinese 穀神穀神 (that is, "Planet of the Deity of Grain"), Pallada - 智 神神 (i.e., "Planet of the Deity of Wisdom"), etc.

There were three paradoxical cases when asteroids had time to get their own name even before receiving a permanent sequence number (that is, before their orbit was reliably calculated). Such (1862) Apollo (Opened in 1932, but the permanent number received only in 1973), (2101) Adonis (Opened in 1936, but the permanent number received only in 1977) and (69230) Hermes (Opened in 1937, but the permanent number received only in 2003). In the interval between the date of discovery and the date of the assignment of a permanent number, these asteroids were considered "lost". "Lost", but later "re-found" asteroids are about two dozen. Asteroids, observed in only few days and finally lost (well, that is, not yet found), there are about 1-2 tens of thousands.

Despite the fact that the nomenclature of the celestial bodies is a thing as if very serious, it has many examples of non-seeing, oddities and, it would seem unacceptable coincidences. For example, many asteroids and satellites of large planets have the same names: Europe (Jupiter satellite) and asteroid (52) Europe, Pandora (Saturnon Satellite) and asteroid (55) Pandora etc. Sometimes the names coincide, but have miscellaneous origin: so, asteroid (218) Bianca was named after Austrian opera singer Bianki (real name - Berta Schwartz), and the satellite of Uranus Bihanka was named after the character from the play of Shakespeare "Taming Shrews". Often the names are similar and in some languages \u200b\u200beven "intersect": for example, the satellite of Jupiter Callisto in languages \u200b\u200busing the Latin, is indicated as Callisto, while asteroid (204) Callisto - Already like Kallisto.

Finally, quite often asteroids have different namesBut at the same time, these names refer to the same reference (often we are talking about situations when analogues between Greek and Roman mythological characters were used for the name). So, besides the moon (satellite land) there is an asteroid (580) Selena (Selena - Greek Name of the Moon), the name of the asteroid (4341) Poseidon He is a Greek analogue latin name Planet Neptune. Asteroids (433) Eros, (763) Cupid and (1221) Amur Send to the same reference. Compare Also (2063) Bakhus and (3671) Dionysis. Or here are more funny "intersections": (1125) China and (3789) Zhongo (Zhongo - China name in Chinese), (14335) Aleposov and (152217) acuse (both are named after the Soviet and Ukrainian astronomer Alexander Osipov).

BUILDING ON MANGAY
To begin with, I recall the question: in what kind of crescent and what kind of order was the celestial body with a temporary designation 2003 VB 12?

Answer: This asteroid has become the 302nd asteroid, open for the first half of November 2003. The year of discoveries is clear. The first letter V indicates the first half of November (V - 22nd the letter of the Latin alphabet, but the letter I is not used in this system, 22 minus 1 gives 21, that is, it is the first half of the eleventh month). The digital index 12 shows that the sequence of twenty-five "second" letters (I remind - I not used) repeated 12 times (that is, we multiply 12 on 25 we get 300). Further, we look at the second letter in the designation - b, the second letter of the Latin alphabet. We add 2 to 300 - we get 302. We are talking about a temporary designation assigned to the body, which is now more famous as a transneptune sector.