Comets and their research using spacecraft. Information about comets. comet movement. comet names

Comet is a small celestial body
misty looking, circling
around the Sun, usually along elongated
orbits. When approaching the Sun, a comet
forms a coma and sometimes a tail of gas and dust.

General information
Presumably long-period comets
fly to us from the Oort Cloud, in which
a huge number of cometary nuclei. The bodies that are
on the outskirts solar system, as a rule, consist
from volatile substances (water, methane and other
ice) that evaporates as it approaches the sun.

More than 400 short-period comets have been discovered so far. Many of
they are included in the so-called families. For example, approximately 50 of the most
short-period comets (their complete revolution around the Sun lasts 3-10 years)
form the Jupiter family. Slightly smaller than the families of Saturn, Uranus and
Neptune.

Comets coming from deep space look like nebulous objects
which stretches the tail, sometimes reaching a length of several million
kilometers. The nucleus of a comet is a body of solid particles and ice, enveloped in
foggy shell, which is called a coma. A nucleus with a diameter of several
kilometers may have around him someone 80 thousand km across. streams
sunlight knocks gas particles out of the coma and throws them back, pulling them into
a long smoky tail that follows her through space.

The brightness of comets depends very much on their distance from the Sun. Of all the comets
a very small part approaches the Sun and Earth enough to be able to
see naked eye. The most notable ones are sometimes referred to as the "big ones".
(great) comets.

The structure of comets
Comets consist of a nucleus and a bright, hazy shell (coma) that surrounds it.
composed of gases and dust. In bright comets, as they approach the Sun,
"tail" - a faint luminous band, which, as a result of light pressure and
the action of the solar wind is most often directed in the opposite direction from ours.
shone the side. The tails of celestial wanderers of comets differ in length and shape. At
some comets they stretch across the sky. Comet tails do not have sharp outlines
and are almost transparent - stars are clearly visible through them. Its composition is varied:
gas or the smallest dust particles, or a mixture of both.
Comet tails are:
straight and narrow
directed straight from
sun;
wide and slightly
twisted,
evading the sun;
short, strong
avoided
central luminary.

The history of the discovery of comets
For the first time, I. Newton calculated the orbit of a comet from observations of its movement against the background
stars and made sure that it, like the planets, moved in the solar system under
by the gravitational force of the sun. Halley calculated and established that the comets observed
in 1531, 1607 and 1682, is the same luminary, periodically returning to
Sun. At aphelion, the comet leaves the orbit of Neptune and returns after 75.5 years
back to earth and sun. Halley first predicted the appearance of a comet in 1758. Through
many years after his death, she really appeared. She was named
Halley's comet and saw it back in 1835 and in 1910 and in 1986.

Halley's Comet is a bright short-period comet returning to the Sun.
every 75-76 years. It is the first comet to have an elliptical
orbit and set the frequency of returns. Named after E. Halley. Despite
that many brighter long-period comets appear every century, the comet
Halley is the only short-period comet that is clearly visible.
with the naked eye. During the 1986 appearance, Halley's Comet became the first
comet explored with spacecraft, including Soviet
vehicles "Vega-1" and "Vega-2", which provided data on the structure of the cometary
nuclei and mechanisms of formation of coma and comet tail.

Comets and Earth
The masses of comets are negligible - about a billion times less than the mass of the Earth, and
the density of matter from their tails is practically zero. Therefore, "heavenly
guests" do not affect the planets of the solar system. In May 1910 the Earth, for example,
passed through the tail of Halley's comet, but no change in the motion of our
the planet didn't happen.
On the other hand, the collision of a large comet with a planet can cause
large-scale consequences in the atmosphere and magnetosphere of the planet. good and
a rather qualitatively studied example of such a collision was
Comet Shoemaker-Levy 9 collides with Jupiter in July 1994.

1. A giant cluster of stars, planets, gases, dust, forming something like an island, slowly rotating in outer space. (Galaxy.)

2. Star-like planets, small bodies of the solar system. (Asteroids.)

3. The ocean of air surrounding the Earth and having a height of several hundred kilometers. (Atmosphere.)

5. Part of the Sun's atmosphere extending for millions of kilometers. (Crown.)

6. This planet of the solar system bears the name of the goddess of beauty and love, the brightest planet, eclipsing all the stars with its brilliance. (Venus.)

7. Celestial body small sizes, consisting of frozen water and gas mixed with dust particles and stones. It moves around the Sun in an elongated orbit and has a "tail". In ancient times, they were called "tailed monsters." (Comet.)

8. An outstanding Greek scientist of antiquity, the creator of the theory of the sky (II century AD). (Ptolemy.)

9. The giant planet, named after the god Olympus, the lord of lightning. She is a hundred times more earth and is surrounded by 16 satellites. (Jupiter.)

10. Foggy spots in the starry sky from a cluster of stars that form. (Milky Way.

11. A group of stars that form letters and shapes familiar to us. (Constellation.)

12. The constellation, located next to the constellation Hounds Dogs and received the title of shepherd. (Bootes.)

14. Astronomer, on whose monument the words are written: "Stopping the Sun, moving the Earth." His main discovery is the rotation of the Earth around the Sun. (Copernicus.)

15. English astronomer and geophysicist who built the first sundial. He drew the attention of scientists to nebulae and comets. (Halley.)

These "tailed" inhabitants of the solar system are comets. The very name of the comet in Greek means "hairy", "shaggy". AT ancient greece, and then in the Middle Ages, comets were usually depicted as severed heads with flying hair.

Comet Ikeya-Janga .
She was visible in March 2002. It is famous, in particular, for the fact that it was visible in the sky near the famous galaxy of the Andromeda Nebula.

Comets are shapeless cosmic bodies in the solar system. They move in highly elongated elliptical orbits. Many comets have a very long period of revolution by human standards and is more than 200 years. Such comets are called long-period comets. Comets with a period of less than 200 years are called short-period comets. Currently, several dozen long-period and more than 400 short-period comets are known.

Comet orbit compared to planetary orbits

These space objects have an insignificant mass and do not reveal themselves in anything far from the Sun. Comets consist of a stone or metal core enclosed in an icy shell of frozen gases (carbon dioxide, ammonia). As it approaches the Sun, the comet begins to evaporate, forming a "coma" - a cloud of dust and gas that surrounds the nucleus. Moreover, these substances of the comet pass into the gaseous state immediately from the solid, bypassing the liquid - such a phase transition is called sublimation. The nucleus and coma form the head of the planet. As it approaches the Sun, the gas cloud forms a huge gas plume - a tail tens or even hundreds of millions of kilometers long.

Light rays and streams emanating from the Sun electrical particles deflect comet tails in the opposite direction from the luminary. The same solar wind causes the glow of rarefied gas in the tails of comets.

comet parts
Pay attention to two tails - dust and plasma

The bulk of the comet's mass is concentrated in its nucleus, but 99.9% of the light radiation comes from the tail, because the nucleus is very compact, and also has a low reflectivity.

Large comets can remain visible for several weeks. Having circled the Sun, they move away and disappear from the field of view. Many comets are observed regularly.

Comet McNaught .
This comet became a real sensation in January 2007. Bright, with a huge fan-shaped tail, she did not leave indifferent among those who were lucky enough to see her. But in all its glory, Comet McNaught was observed only in the southern hemisphere of the planet.

Comets attract everyone's attention. Their appearance in ancient times caused fear and was perceived as a heavenly sign of future terrible events.

human history in ancient times was very full of various tragic events, such as wars, epidemics, palace coups, assassination of rulers. Some of these events were accompanied by the appearance of bright comets, and the predictors began to connect the phenomena of heaven and earth with each other.
This famous antique French tapestry from the time of William the Conqueror shows Halley's Comet as it appeared in 1066. That year there was a battle in which the duke defeated the army of the Anglo-Saxon king Harold II and took the English throne. This victory was then attributed to the influence of a heavenly sign - a comet. The inscription on the tapestry says - "marvel at the star."

In fact, the comet cannot have any noticeable impact on our planet because of its insignificant size: the mass of the comet is about a billion times less than the mass of the Earth, and the density of the tail matter is almost zero. So, in May 1910, the Earth passed through the tail of Halley's comet, but did not experience any changes.

The death of comet Shoemaker-Levy 9 in the gravitational field of Jupiter
The comet approached Jupiter in 1992 and was torn apart by its gravity. In July 1994, its fragments collided with Jupiter, causing fantastic effects in the planet's atmosphere.
The comet was discovered on March 24, 1993, when it was already a chain of fragments.

By their origin, comets are remnants of the primary matter of the solar system. Therefore, their study helps to restore the picture of the formation of planets, including the Earth.

The most famous comet is Halley's Comet.

Comet Halley

The orbital period of Halley's comet around the Sun is 76 years, the semi-major axis of the orbit is 17.8 AU. e, eccentricity 0.97, orbital inclination to the ecliptic plane 162.2°, perihelion distance 0.59 AU. e. The size of Halley's comet is 14 km long and 7.5 km across.

It was thanks to her that the English astronomer Edmund Halley discovered the periodicity of the appearance of comets. Comparing the parameters of the orbits of several bright comets of the past, he concluded that these were not different comets, but the same one, periodically returning to the Sun along a highly elongated path. He predicted the return of this comet, and his prediction was brilliantly confirmed. This comet was named after him.

From 239 BC Halley's comet has been observed 30 times. The last time it appeared in 1986 and the next time it will be observed in 2061. On the last visit of a space guest to our region, it was studied at close range by 5 interplanetary probes - two Japanese ("Sakigake" and "Suisei"), two Soviet ( "Vega-1" and "Vega-2") and one European ("Giotto").

These "tailed" inhabitants of the solar system are comets. The very name of the comet in Greek means "hairy", "shaggy". In ancient Greece, and later in the Middle Ages, comets were usually depicted as severed heads with flying hair.

.
She was visible in March 2002. It is famous, in particular, for the fact that it was visible in the sky near the famous galaxy of the Andromeda Nebula.

Comet orbit compared to planetary orbits

Light rays emanating from the Sun and streams of electrical particles deflect comet tails in the opposite direction from the luminary. The same solar wind causes the glow of rarefied gas in the tails of comets.

comet parts
Pay attention to two tails - dust and plasma

The bulk of the comet's mass is concentrated in its nucleus, but 99.9% of the light radiation comes from the tail, because the nucleus is very compact, and also has a low reflectivity.

Large comets can remain visible for several weeks. Having circled the Sun, they move away and disappear from the field of view. Many comets are observed regularly.

Comet McNaught.
This comet became a real sensation in January 2007. Bright, with a huge fan-shaped tail, she did not leave indifferent among those who were lucky enough to see her. But in all its glory, Comet McNaught was observed only in the southern hemisphere of the planet.

Comets attract everyone's attention. Their appearance in ancient times caused fear and was perceived as a heavenly sign of future terrible events.

Human history in antiquity was very rich in various tragic events, such as wars, epidemics, palace coups, assassinations of rulers. Some of these events were accompanied by the appearance of bright comets, and the predictors began to connect the phenomena of heaven and earth with each other.
This famous antique French tapestry from the time of William the Conqueror shows Halley's Comet as it appeared in 1066. That year there was a battle in which the duke defeated the army of the Anglo-Saxon king Harold II and took the English throne. This victory was then attributed to the influence of a heavenly sign - a comet. The inscription on the tapestry says - "marvel at the star."

The comet approached Jupiter in 1992 and was torn apart by its gravity. In July 1994, its fragments collided with Jupiter, causing fantastic effects in the planet's atmosphere.
The comet was discovered on March 24, 1993, when it was already a chain of fragments.

By their origin, comets are remnants of the primary matter of the solar system. Therefore, their study helps to restore the picture of the formation of planets, including the Earth.

The most famous comet is Halley's Comet.

Comet Halley

Bibliographic description: Falkovskaya VD, Kosareva VN Comets and their research using spacecraft // Young scientist. - 2015. - No. 3. — S. 132-134..02.2019).

In this paper, I will tell you about comets and their research using spacecraft. First, let's look at the very definition of a comet. A comet is a small, nebulous celestial body that revolves around the Sun in a conic section with an extended orbit. When approaching the Sun, a comet forms a coma and sometimes a tail of gas and dust. It is believed that comets arrive in the solar system from the Oort cloud, which contains a huge number of cometary nuclei. Bodies, as a rule, consist of volatile substances that evaporate when approaching the Sun.

Comets are divided into short-period and long-period comets. At the moment, more than 400 short-period comets have been discovered. Many of them are included in the so-called families. For example, most of the shortest period comets (their full revolution around the Sun lasts 3–10 years) form the Jupiter family. A little smaller than the families of Saturn, Uranus and Neptune. Comets look like nebulous objects with trailing tails sometimes reaching millions of kilometers in length. The nucleus of a comet is a body of solid particles wrapped in a hazy shell called a coma. A nucleus with a diameter of several kilometers can have around it a coma 80,000 km across. Streams of sunlight knock gas particles out of the coma and throw them back, pulling them into a long smoky tail that follows her through space.

The brightness of comets is highly dependent on their distance from the Sun. Of all the comets, only a very small part approaches the Sun and the Earth enough to be seen with the naked eye. The structure of the comet. A comet consists of a nucleus, a coma and a tail. The nucleus of a comet is a solid part, in which almost all of its mass is concentrated. The most common is the Whipple model. According to this model, the core is a mixture of ice interspersed with particles of meteoric matter. With such a structure, layers of frozen gases alternate with dust layers. As the gases heat up, they carry clouds of dust with them. This makes it possible to explain the formation of gas and dust tails in comets. However, according to studies that were carried out using the American automatic station ‘Deep Impact’, the core consists of loose material and is a lump of dust with pores.

The coma is a light foggy shell surrounding the nucleus, consisting of gases and dust. It usually stretches from 100,000 to 1.4 million kilometers from the core. The coma, together with the nucleus, makes up the head of the comet. Coma is made up of three main parts:

a) Internal coma, where the most intense physical and chemical processes take place.

b) Visible coma.

c) Ultraviolet (atomic) coma.

In bright comets, as they approach the Sun, a ‘tail’ is formed - a luminous band, which, as a result of the solar wind, is directed in the opposite direction from the Sun. Comet tails vary in length and shape. For example, the tail of the 1944 comet was 20 million km long. The "Big Comet" of 1680 had a tail 240 million km long. There were also cases of separation of the tail from a comet (Comet Lulin). The tails of comets do not have sharp outlines and are almost transparent, as they are formed from rarefied matter. The composition of the tail is varied: gas or dust particles, or a mixture of both.

The theory of tails and forms of comets was developed by the Russian astronomer Fyodor Bredikhin. He also belongs to the classification of comet tails. Bredikhin proposed three types of comet tails:

a) straight and narrow, directed directly from the Sun;

b) wide and curved, deviating from the Sun;

c) short, strongly deviated from the central luminary.

The particles that make up comets have different compositions and properties and respond differently to solar radiation. Thus, the paths of these particles in space “diverge”, and the tails of space travelers take on different shapes. The speed of the particle is the sum of the speed of the comet and that acquired as a result of the action of the Sun. How far the comet's tail will differ from the direction from the Sun to the comet depends on the mass of the particles and the action of the Sun.

The study of comets. We all know that people have always taken a special interest in comets. Them unusual view and the unexpectedness of appearance served as a source of superstition. The ancients associated the appearance of these cosmic bodies in the sky with impending troubles and the onset of hard times. to the comet "Halley" of the spacecraft "Vega-1" and "Vega-2" and the European "Giotto". Numerous devices of these devices transmitted to Earth images of the comet's nucleus and information about its shell. It turned out that the nucleus of Halley's comet consists of ice, as well as dust particles. They form the shell of a comet, and as it approaches the Sun, some of them pass into the tail. The nucleus of Halley's comet has irregular shape and rotates about an axis that is almost perpendicular to the plane of the comet's orbit.

At present, the study of the Churyumov-Gerasimenko comet is carried out using the Rosetta spacecraft. Let's take a closer look at the Rosetta spacecraft. The Rosetta spacecraft was designed and manufactured by the European Space Agency in collaboration with NASA. It consists of two parts: the Rosetta probe and the Fila descent vehicle. The spacecraft was launched on March 2, 2004 to the Churyumov-Gerasimenko comet. Rosetta is the first spacecraft to orbit a comet.

The work of the apparatus near the comet. In July 2014, Rosetta received the first data on the state of the Churyumov-Gerasimenko comet. The device determined that the comet's nucleus releases about 300 milliliters of water into the surrounding space every second. On August 3, 2014, an image with a resolution of 5.3 meters / pixel was obtained from a distance of 285 km. Images of the surface of the comet were obtained using the OSIRIS system (the scientific image processing system installed on Rosetta). At the beginning of September 2014, a map of the surface was compiled, highlighting several areas, each of which is characterized by a specific morphology. The presence of hydrogen and oxygen in the comet's coma was recorded.

On November 12, the ESA reported that the Philae spacecraft had undocked from the Rosetta probe and descended to the surface of the comet's nucleus. It took about seven hours. During this time, the device took pictures of both the comet itself and the Rosetta probe. Thus, on November 12, 2014, the world's first soft landing of a descent vehicle on the surface of a comet took place. On November 14, the Philae lander completed its main scientific tasks and transmitted all the results from scientific instruments to Earth through the Rosetta.

On November 15, Philae switched to power saving mode. illumination solar panels was too low to charge the batteries and communicate with the machine. According to scientists, as the comet approached the Sun, the amount of energy generated should have increased to values sufficient to turn on the apparatus.

On June 13, 2015, Philae exited the low power mode, communication with the device was established. On August 13, 2015, the Churyumov-Gerasimenko comet reached perihelion - the point of its closest approach to the Sun. This event has a symbolic meaning, since for the first time in the history of space exploration, an automatic station created by man passed along with the comet perihelion. At the point of closest approach to the Sun, the comet and the Rosetta station were at a distance of about 186 million km from our star. In this area, a space object appears once every six and a half years - this is how long the period of revolution of a comet around the Sun lasts. Now the Churyumov-Gerasimenko and Rosetta comets are moving at a speed of approximately 34.2 km / s. The pair is located at a distance of about 265.1 million km from the Earth. The Rosetta science program will last about another year - until September 2016. This will allow to collect a lot of important scientific information in addition to that already received. The European Space Agency announced that the conditions necessary for the emergence of life have been found on the Churyumov-Gerasimenko comet.

The Philae probe found 16 organic compounds rich in carbon and nitrogen on the surface of the comet, including four compounds that had not previously been found on comets. Some of these compounds "play a key role in the synthesis of amino acids, sugars and nucleins," which are essential components for the origin of life, the ESA said in a statement. Formaldehyde, for example, is involved in the formation of ribose, a derivative of which is a component of DNA,” the agency said.

Scientists believe that the presence of such complex molecules in a comet indicates that chemical processes may have played a key role in helping shape the conditions for the emergence of life. A hypothesis has been put forward, according to which microbes of alien origin may be present on the comet. It is the presence of living organisms under the ice that makes it possible to explain the black crust rich in organic compounds. It is impossible to confirm the theory, since neither the Rosetta nor the Philae were equipped with instruments that could look for traces of life.

The members of the Rosetta mission came to the conclusion that the Churyumov-Gerasimenko comet does not have its own magnetic field.

The study of the properties of comets should help researchers shed light on the processes that took place during the formation of objects in the solar system. In particular, the presence magnetic field in comets, this may be evidence that it was due to the magnetic interaction that the smallest particles united with each other. Meanwhile, the absence of its own magnetic field may force scientists to somewhat revise the accepted theory of the formation of objects in the solar system.

Literature:

Comet. https://ru.wikipedia.org/wiki/ %D0 %9A %D0 %BE %D0 %BC %D0 %B5 %D1 %82 %D0 %B0#.D0.98.D0.B7.D1.83. D1.87.D0.B5.D0.BD.D0.B8.D0.B5_.D0.BA.D0.BE.D0.BC.D0.B5.D1.82
Comet Churyumov-Gerasimenko reached perihelion http://www.3dnews.ru/918592?from=related-block
The work of the apparatus near the comet http://tunguska.ru/forum/index.php?topic=1019.0