The largest asteroids and their movement. Asteroids of the Solar System. Asteroids Presentation of the largest asteroids and their movement

Asteroid- a small planet-like celestial body in the Solar System, moving in orbit around the Sun. Asteroids, also known like small planets, are significantly smaller in size than the planets.

Term asteroid(from ancient Greek. ἀστεροειδής - “like a star”, from ἀστήρ - “star” and εῖ̓δος - “appearance, appearance, quality”) was introduced William Herschel based on the fact that these objects, when observed through a telescope, looked like points of stars - in contrast to the planets, which when observed through a telescope, looked like disks. Exact definition of the term "asteroid" is still not established.

To date, tens of thousands of asteroids have been discovered in the Solar System. Most currently known asteroids are concentrated within the asteroid belt, located between the orbits of Mars and Jupiter. The largest asteroid in the solar system is considered Ceres, having dimensions of approximately 975 × 909 km.

Two other largest asteroids Pallas And Vesta have a diameter of ~500 km.

Pallas

Vesta

At first, asteroids were given the names of heroes Roman and Greek mythology, later the discoverers gained the right to call it whatever they wanted, for example, by their own name. At first, asteroids were given predominantly female names; only asteroids with unusual orbits (for example, Icarus, approaching the Sun closer than Mercury).

The larger and heavier the asteroid, the greater the danger it poses, but in this case it is much easier to detect it. The most dangerous asteroid at the moment is considered Apophis, with a diameter of about 300 meters, in a collision with which, in the event of an accurate hit, a large city can be destroyed, but such a collision does not pose any threat to humanity as a whole.

Meteorite- a solid body of cosmic origin that fell to the surface Earth. Most of the meteorites found weigh between several grams up to several kilograms. The largest meteorite ever found is Goba(weight 60 tons).

At the site of the fall of a large meteorite, a crater. One of the most famous craters in the world - Arizonan. It is believed that the largest meteorite crater on Earth is Wilkes Land Crater(diameter about 500 km).

Arizona Crater

The process of meteorites falling to Earth.
The meteor body enters the Earth's atmosphere at a speed of about 11-25 km/sec. It begins to warm up and glow. Due to ablation(burning and blowing away by the oncoming flow of particles of the meteoric body’s substance), the mass of the body that reaches the ground may be less than its mass at the entrance to the atmosphere. Traces of the combustion of a meteoroid in the atmosphere can be found along almost the entire trajectory of its fall. If the meteoroid does not burn up in the atmosphere, then as it slows down it loses the horizontal component of its speed. This leads to a change in the trajectory of the fall. As it slows down, the glow of the meteor body decreases and it cools down. In addition, the meteor body may break into fragments, which leads to fallout Meteor shower.

Interesting Facts.
The only documented case of a meteorite hitting a person occurred on November 30, 1954 in Alabama. A meteorite weighing about 4 kg pierced the roof of a house and ricocheted Anna Elizabeth Hodges on the arm and thigh. The woman received bruises.

Using the Internet, prepare a presentation on “The Largest Asteroids and Their Motion.”

This rather large celestial body (diameter 975 * 909 km) has been many things since its discovery: both a full-fledged planet of the solar system and an asteroid, and since 2006 it has acquired a new status - a dwarf planet. The last name is the most correct, since Ceres is not the main one in its orbit, but only the largest in the asteroid belt. It was discovered quite by accident by the Italian astronomer Piazzi in 1801. Ceres has a spherical shape (unusual for asteroids) with a rocky core and a crust of water ice and minerals. The distance between the closest point in the orbit of this solar satellite and the Earth is 263 million kilometers. Its path lies between Mars and Jupiter, but there is some tendency towards chaotic movement (which increases the chances of collisions with other asteroids and a change in orbit). It is not visible to the naked eye from the surface of our planet - it is only a 7th magnitude star. Pallas Size 582 * 556 kilometers, and it is also part of the asteroid belt. The angle of Pallas' rotation axis is very high - 34 degrees (for other celestial bodies it does not exceed 10). Pallas moves in an orbit with a large degree of deviation, which is why its distance to the Sun changes all the time. This is a carbon asteroid, rich in silicon and is of interest in the future from the point of view of mining. Vesta This is the heaviest asteroid to date, although it is smaller in size than the previous ones. Due to the composition of the rock, Vesta reflects 4 times more light than Ceres, although its diameter is half that. It turns out that this is the only asteroid whose movement can be observed with the naked eye from the surface of the Earth when it approaches once every 3-4 years to a minimum distance of 177 million kilometers. Its movement is carried out along the inner part of the asteroid belt and never crosses our orbit. Interestingly, with a length of 576 kilometers, there is a crater with a diameter of 460 kilometers on its surface. In general, the entire asteroid belt around Jupiter is a giant quarry where celestial bodies collide with each other, fly into pieces and change their orbits - but how Vesta survived a collision with such a large object and retained its integrity remains a mystery. Its core consists of heavy metal, and its crust is made of light rock. Hygeia This asteroid does not intersect with our orbit and revolves around the Sun. A very dim celestial body, although it has a diameter of 407 kilometers, was discovered later than the others. This is the most common type of asteroid, with carbonaceous content. Typically, observing Hygia requires a telescope, but at its closest approach to Earth, it can be seen with binoculars.

Asteroid- a small planet-like celestial body in the Solar System, moving in orbit around the Sun. Asteroids, also known like small planets, are significantly smaller in size than the planets.

Term asteroid(from ancient Greek. ἀστεροειδής - “like a star”, from ἀστήρ - “star” and εῖ̓δος - “appearance, appearance, quality”) was introduced William Herschel based on the fact that these objects, when observed through a telescope, looked like points of stars - in contrast to the planets, which when observed through a telescope, looked like disks. Exact definition of the term "asteroid" is still not established.

To date, tens of thousands of asteroids have been discovered in the Solar System. Most currently known asteroids are concentrated within the asteroid belt, located between the orbits of Mars and Jupiter. The largest asteroid in the solar system is considered Ceres, having dimensions of approximately 975 × 909 km.

Two other largest asteroids Pallas And Vesta have a diameter of ~500 km.

Pallas

Vesta

At first, asteroids were given the names of heroes Roman and Greek mythology, later the discoverers gained the right to call it whatever they wanted, for example, by their own name. At first, asteroids were given predominantly female names; only asteroids with unusual orbits (for example, Icarus, approaching the Sun closer than Mercury).

The larger and heavier the asteroid, the greater the danger it poses, but in this case it is much easier to detect it. The most dangerous asteroid at the moment is considered Apophis, with a diameter of about 300 meters, in a collision with which, in the event of an accurate hit, a large city can be destroyed, but such a collision does not pose any threat to humanity as a whole.

Meteorite- a solid body of cosmic origin that fell to the surface Earth. Most of the meteorites found weigh between several grams up to several kilograms. The largest meteorite ever found is Goba(weight 60 tons).

At the site of the fall of a large meteorite, a crater. One of the most famous craters in the world - Arizonan. It is believed that the largest meteorite crater on Earth is Wilkes Land Crater(diameter about 500 km).

Arizona Crater

The process of meteorites falling to Earth.
The meteor body enters the Earth's atmosphere at a speed of about 11-25 km/sec. It begins to warm up and glow. Due to ablation(burning and blowing away by the oncoming flow of particles of the meteoric body’s substance), the mass of the body that reaches the ground may be less than its mass at the entrance to the atmosphere. Traces of the combustion of a meteoroid in the atmosphere can be found along almost the entire trajectory of its fall. If the meteoroid does not burn up in the atmosphere, then as it slows down it loses the horizontal component of its speed. This leads to a change in the trajectory of the fall. As it slows down, the glow of the meteor body decreases and it cools down. In addition, the meteor body may break into fragments, which leads to fallout Meteor shower.

Interesting Facts.
The only documented case of a meteorite hitting a person occurred on November 30, 1954 in Alabama. A meteorite weighing about 4 kg pierced the roof of a house and ricocheted Anna Elizabeth Hodges on the arm and thigh. The woman received bruises.

Asteroids, or small planets, are much smaller in size than such solar system bodies as Earth, Venus and even Mercury. However, they cannot but be considered full-fledged “residents” of our piece of the Galaxy.

Main belt

Asteroids of the Solar System are concentrated in several zones. The most impressive part of them is located between the orbits of Mars and Jupiter. This cluster of small bodies was called the Main Cluster. The mass of all objects located here is negligible by cosmic standards: it makes up only 4% of the lunar mass. Moreover, the largest asteroids make a decisive contribution to this parameter. Both their movement and the movement of their smaller counterparts, as well as parameters such as composition, shape and origin, attracted the attention of astronomers at the beginning of the 19th century: Ceres, previously considered the largest asteroid, and now classified as a dwarf planet, was discovered the first of January 1801.

Beyond Neptune

The Kuiper belt, the Orth cloud and the scattered disk began to be considered and studied as places of accumulation of a large number of small ones a little later. The first of these is located beyond the orbit of Neptune. It was opened only in 1992. According to researchers, the Kuiper belt is much longer and more massive than a similar formation between Mars and Jupiter. Small bodies located here differ from the objects of the Main Belt in composition: methane, ammonia and water here prevail over solid rocks and metals characteristic of the “inhabitants” of the Asteroid Belt.

The existence of the Orth cloud has not been proven today, but it corresponds to many theories describing the Solar system. Presumably the Orta cloud, which is a spherical region, is located beyond the orbits of the planets, at a distance of approximately from the Sun. Space objects consisting of ammonia, methane and water ice are located here.

The scattered disk region overlaps somewhat with the Kuiper Belt. Scientists do not yet know its origin. Objects consisting of different types of ice are also placed here.

Comparing a comet with an asteroid

To accurately understand the essence of the issue, it is necessary to distinguish between two astronomical concepts: “comet” and “asteroid”. Until 2006, there was no certainty regarding the differences between these objects. At the IAU General Assembly in that year, specific characteristics were assigned to the comet and asteroid, allowing each to be more or less confidently assigned to a specific category.

A comet is an object moving in a very elongated orbit. When approaching the Sun as a result of sublimation of ice located near the surface, the comet forms a coma - a cloud of dust and gas that grows as the distance between the object and the star decreases and is often accompanied by the formation of a “tail.”

Asteroids do not form comas and, as a rule, have less elongated orbits. Those of them that move along trajectories similar to those of comets are considered the nuclei of so-called extinct comets (an extinct or degenerate comet is an object that has lost all volatile substances and therefore does not form a coma).

The largest asteroids and their movement

There are very few truly large objects by cosmic standards in the Main Asteroid Belt. Most of the mass of all bodies located between Jupiter and Mars falls on four objects - Ceres, Vesta, Pallas and Hygiea. The first was considered the largest asteroid until 2006, then it was given the status of Ceres - an almost round body with a diameter of about 1000 km. Its mass is approximately 32% of the total mass of all known objects in the belt.

The most massive object after Ceres is Vesta. In terms of size, only Pallas is ahead of it among the asteroids (after Ceres was recognized as a dwarf planet). Pallas is also distinguished from the rest by its unusually strong axis tilt.

Hygiea is the fourth largest Main Belt object in terms of size and mass. Despite its size, it was discovered much later than several smaller asteroids. This is due to the fact that Hygiea is a very dim object.

All named bodies rotate around the Sun in the same direction as the planets and do not cross the Earth.

Features of orbits

The largest asteroids and their movement obey the same laws as the movements of other similar bodies in the belt. Their orbits are constantly influenced by the planets, especially the giant Jupiter.

All asteroids rotate in slightly eccentric orbits. The movement of asteroids exposed to Jupiter takes place in slightly shifting orbits. These displacements can be described as oscillations around some average position. The asteroid spends up to several hundred years on each such oscillation, so observational data today are not enough to clarify and test theoretical constructions. However, in general, the hypothesis of changing orbits is generally accepted.

The result of shifting orbits is an increased possibility of collisions. In 2011, evidence was obtained to suggest that Ceres and Vesta may collide in the future.

The largest asteroids and their movements are constantly under the close attention of scientists. Features of changes in their orbits and other characteristics shed light on some cosmic patterns, which, in the process of data analysis, are often extrapolated to objects larger than asteroids. The movement of asteroids is also studied with the help of spacecraft, which temporarily become satellites of certain objects. One of them entered Ceres orbit on March 6, 2015.

Asteroids Completed by: Student

An asteroid is a relatively small celestial body in the Solar System moving in orbit around the Sun.

Asteroids are significantly smaller in mass and size than planets, have an irregular shape, and do not have an atmosphere, although they may also have satellites.

The main parameter by which classification is carried out is body size. Asteroids are considered bodies with a diameter of more than 30 m; smaller bodies are called meteoroids.

Currently, hundreds of thousands of asteroids have been discovered in the Solar System. It is estimated that there may be from 1.1 to 1.9 million objects in the Solar System that are larger than 1 km. Most currently known asteroids are concentrated within the asteroid belt, located between the orbits of Mars and Jupiter.

Ceres, measuring approximately 975×909 km, was considered the largest asteroid in the Solar System, but since August 24, 2006, it received the status of a dwarf planet. The other two largest asteroids, Pallas and Vesta, have a diameter of ~500 km. Vesta is the only object in the asteroid belt that can be observed with the naked eye.

The total mass of all main belt asteroids is only about 4% of the mass of the Moon. The mass of Ceres is about 32% of the total, and together with the three largest asteroids Vesta (9%), Pallas (7%), Hygeia (3%) - 51%, that is, the vast majority of asteroids have an insignificant mass by astronomical standards.

Asteroids are grouped into groups and families based on the characteristics of their orbits. Usually the group is named after the first asteroid that was discovered in a given orbit. Groups are relatively loose formations, while families are denser, formed in the past during the destruction of large asteroids from collisions with other objects.

The general classification of asteroids is based on the characteristics of their orbits and a description of the visible spectrum of sunlight reflected by their surface. Class C - carbon, 75% of known asteroids. Class S - silicate, 17% of known asteroids. Class M - metal, most others.

The number of asteroids decreases noticeably as their size increases. Approximate number of asteroids N with diameter greater than D

The danger of asteroids At the moment there are no asteroids that could significantly threaten the Earth. The larger and heavier the asteroid, the greater the danger it poses, but in this case it is much easier to detect it. The most dangerous asteroid at the moment is considered to be Apophis, with a diameter of about 300 m, a collision with which, in the event of an accurate hit, can destroy a large city, but such a collision does not pose any threat to humanity as a whole. Asteroids larger than 10 km in diameter can pose a global threat. All asteroids of this size are known to astronomers and are in orbits that cannot lead to a collision with the Earth.