What is cosmic dust definition. The mystery of stardust solved
Scientists at the University of Hawaii made sensational discovery — cosmic dust contains organic matter , including water, which confirms the possibility of transferring various forms of life from one galaxy to another. Comets and asteroids traveling through space regularly bring masses of stardust into the atmosphere of planets. Thus, interstellar dust acts as a kind of “transport” that can deliver water and organic matter to Earth and other planets solar system. Perhaps, once upon a time, a stream of cosmic dust led to the emergence of life on Earth. It is possible that life on Mars, the existence of which causes much controversy in scientific circles, could have arisen in the same way.
The mechanism of water formation in the structure of cosmic dust
As they move through space, the surface of interstellar dust particles is irradiated, which leads to the formation of water compounds. This mechanism can be described in more detail as follows: hydrogen ions present in solar vortex flows bombard the shell of cosmic dust grains, knocking out individual atoms from the crystalline structure of the silicate mineral - the main building material intergalactic objects. As a result of this process, oxygen is released, which reacts with hydrogen. Thus, water molecules containing inclusions of organic substances are formed.
Colliding with the surface of the planet, asteroids, meteorites and comets bring a mixture of water and organic matter to its surface
What cosmic dust- a companion of asteroids, meteorites and comets, carries molecules of organic carbon compounds, it was known before. But it has not been proven that stardust also transports water. Only now have American scientists discovered for the first time that organic matter transported by interstellar dust particles together with water molecules.
How did water get to the Moon?
The discovery of scientists from the United States may help lift the veil of mystery over the mechanism of formation of strange ice formations. Despite the fact that the surface of the Moon is completely dehydrated, an OH compound was discovered on its shadow side using sounding. This find indicates the possible presence of water in the depths of the Moon.
The far side of the Moon is completely covered with ice. Perhaps it was with cosmic dust that water molecules reached its surface many billions of years ago
Since the era of the Apollo rovers in lunar exploration, when lunar soil samples were brought to Earth, scientists have come to the conclusion that sunny wind causes changes in chemical composition star dust covering the surfaces of planets. Even then there was a debate about the possibility of the formation of water molecules in the thickness of cosmic dust on the Moon, but available at that time analytical methods studies were unable to either prove or disprove this hypothesis.
Cosmic dust is a carrier of life forms
Due to the fact that water is formed in a very small volume and is localized in a thin shell on the surface cosmic dust, only now it has become possible to see it using an electron microscope high resolution. Scientists believe that a similar mechanism for the movement of water with molecules of organic compounds is possible in other galaxies where it revolves around the “parent” star. In their further research, scientists expect to identify in more detail which inorganic and organic matter carbon-based are present in the structure of stardust.
Interesting to know! An exoplanet is a planet that is located outside the solar system and orbits a star. On this moment In our galaxy, about 1000 exoplanets have been visually discovered, forming about 800 planetary systems. However, indirect detection methods indicate the existence of 100 billion exoplanets, of which 5-10 billion have parameters similar to the Earth, that is, they are. A significant contribution to the mission of searching for planetary groups similar to the Solar System was made by the Kepler astronomical telescope satellite, launched into space in 2009, together with the Planet Hunters program.
How could life originate on Earth?
It is very likely that comets traveling through space at high speeds are capable of creating enough energy when colliding with a planet to begin the synthesis of more complex organic compounds, including amino acid molecules, from ice components. A similar effect occurs when a meteorite collides with the icy surface of a planet. The shock wave creates heat, which triggers the formation of amino acids from individual molecules of cosmic dust processed by the solar wind.
Interesting to know! Comets are composed of large blocks of ice formed by the condensation of water vapor during the early creation of the solar system, approximately 4.5 billion years ago. In their structure, comets contain carbon dioxide, water, ammonia, and methanol. These substances, during the collision of comets with the Earth, at an early stage of its development, could produce sufficient quantity energy for the production of amino acids - building proteins necessary for the development of life.
Computer modeling has demonstrated that icy comets that crashed onto the Earth's surface billions of years ago may have contained prebiotic mixtures and simple amino acids such as glycine, from which life on Earth subsequently originated.
Amount of energy released during a collision celestial body and the planet, enough to start the process of amino acid formation
Scientists have discovered that icy bodies with identical organic compounds, characteristic of comets, can be found inside the solar system. For example, Enceladus, one of the satellites of Saturn, or Europa, a satellite of Jupiter, contain in their shell organic matter, mixed with ice. Hypothetically, any bombardment of satellites by meteorites, asteroids or comets could lead to the emergence of life on these planets.
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Scientists have noticed a large cloud of cosmic dust created by a supernova explosion.
Cosmic dust can provide answers to questions about how life appeared on Earth- whether it originated here or was brought with comets that fell to Earth, whether water was here from the very beginning or was it also brought from space.
A recent image of a cloud of cosmic dust that occurred after a supernova explosion proves thatsupernovaecapable of producing enough cosmic dust to create planets like our Earth.
Moreover, scientists believe that this dust is enough to create thousands suchplanets like earth.
Telescope data shows warm dust ( White color), which survived inside the supernova remnant. The supernova remnant cloud Sagittarius A Vostok is shown in blue. Radio emission (red) indicates the collision of the expanding shock wave with surrounding interstellar clouds (green).
It is worth noting that cosmic dust participated in the creation of both our planet and many other cosmic bodies. Sheconsists of small particles up to 1 micrometer in size.
It is now known that comets contain primordial dust that is billions of years old and played a major role in the formation of the Solar System. By examining this dust you can learn a lot abouthow the Universe and our solar system began to be createdin particular, and also learn more about the composition of the first organic matter and water.
According to Ryan Lau of Cornell University in Ithaca, New York,flash,recentlyphotographed by telescope, occurred 10,000 years ago, and the result was a cloud of dust large enough tothere are 7,000 planets similar to Earth.
Observations of a supernova (Supernova)
By using Stratospheric Observatory for Infrared Astronomy (SOFIA), scientists studied the intensity of radiation and were able to calculate total weight cosmic dust in the cloud.
It is worth noting that SOFIA is a joint a project of NASA and the German Aviation and Space Center. The goal of the project is to create and use a Cassegrain telescope on board a Boeing 474 aircraft.
During the flight at an altitude of 12-14 kilometers, a telescope with a circumference of 2.5 meters is capable of creating photographs of space close in quality to those taken by space observatories.
Led by Lau, the team used the SOFIA telescope with a special cameraFORCAST on board,to take infrared images of a cloud of cosmic dust, also known as the Sagittarius A Vostok supernova remnant. FORCAST isinfrared camera for detecting low-contrast objects.
Where does cosmic dust come from? Our planet is surrounded by a dense air shell - the atmosphere. The composition of the atmosphere, in addition to the gases known to everyone, also includes solid particles - dust.
It mainly consists of soil particles that rise upward under the influence of the wind. During volcanic eruptions, powerful dust clouds. Above big cities There are whole “dust caps” hanging, reaching a height of 2-3 km. The number of dust particles in one cubic meter. cm of air in cities reaches 100 thousand pieces, while in clean mountain air there are only a few hundred of them. However, dust earthly origin rises to relatively low altitudes - up to 10 km. Volcanic dust can reach a height of 40-50 km.
Origin of cosmic dust
The presence of dust clouds has been established at altitudes significantly exceeding 100 km. These are the so-called " noctilucent clouds"consisting of cosmic dust.
The origin of cosmic dust is extremely diverse: it includes the remains of disintegrated comets and particles of matter ejected by the Sun and brought to us by the force of light pressure.
Naturally, under the influence of gravity, a significant part of these cosmic dust particles slowly settles to the ground. The presence of such cosmic dust was discovered on high snowy peaks.
Meteorites
In addition to this slowly settling cosmic dust, hundreds of millions of meteors burst into our atmosphere every day - what we call “falling stars”. Flying at cosmic speeds of hundreds of kilometers per second, they burn out from friction with air particles before they reach the surface of the earth. The products of their combustion also settle on the ground.
However, among the meteors there are also exceptionally large specimens that reach the surface of the earth. Thus, the fall of the great Tunguska meteorite at 5 o'clock in the morning on June 30, 1908, accompanied by a number of seismic phenomena, noted even in Washington (9 thousand km from the fall site) and indicating the power of the explosion when the meteorite fell. Professor Kulik, who with exceptional courage examined the site of the meteorite fall, found a thicket of windfall surrounding the site of the fall within a radius of hundreds of kilometers. Unfortunately, he was unable to find the meteorite. An employee of the British Museum, Kirkpatrick, made a special trip to the USSR in 1932, but did not even get to the site of the meteorite fall. However, he confirmed the assumption of Professor Kulik, who estimated the mass fallen meteorite 100-120 tons.
Cloud of cosmic dust
An interesting hypothesis is that of Academician V.I. Vernadsky, who considered it possible that it was not a meteorite that would fall, but a huge cloud of cosmic dust moving at colossal speed.
Academician Vernadsky confirmed his hypothesis with the appearance these days of a large number of luminous clouds moving at high altitudes at a speed of 300-350 km per hour. This hypothesis could also explain the fact that the trees surrounding the meteorite crater remained standing, while those located further were knocked down by the blast wave.
In addition to the Tunguska meteorite, it is also known whole line craters of meteorite origin. The first of these craters to be surveyed can be called the Arizona crater in Devil's Canyon. It is interesting that not only fragments of an iron meteorite were found near it, but also small diamonds formed from carbon from high temperature and pressure during the fall and explosion of the meteorite.
In addition to the indicated craters, indicating the fall of huge meteorites weighing tens of tons, there are also smaller craters: in Australia, on the island of Ezel and a number of others.
In addition to large meteorites, quite a lot of smaller ones fall out every year - weighing from 10-12 grams to 2-3 kilograms.
If the Earth were not protected by a thick atmosphere, we would be bombarded every second by tiny cosmic particles traveling at speeds faster than bullets.
That the cosmic vacuum is not as empty as the average person thinks, we still cannot help but note that it can hardly be called “filled”. Hydrogen, calcium, iron - all this is present in the space environment, but in such quantities that without precise equipment it is useless to even try to look for it.
Why should we be surprised by the fact that right up to 1930, most scientists were convinced that in the space between the stars there was no medium that would cause noticeable absorption of starlight. Therefore, when determining the distance to a star, we used the well-known law of attenuation of the brightness of a light source in proportion to the square of the distance to it. However, in doing so, scientists made a terrible mistake.
The point is that this position, which is valid in the case of a completely transparent space, turns out to be incorrect in the presence of an absorbing medium. And the fact that the space between the stars is not completely transparent was pointed out a hundred years ago by the outstanding Russian scientist V. Ya. Struve, but his ideas were not appreciated by his contemporaries.
Fortunately, in the early 1930s, the scientist was proven right. Now no one called space a completely transparent void, and the fault of distortions not taken into account by scientists of the past was nothing more than cosmic dust.
Since then, astronomers began to carefully study the distribution of absorbing matter in space, to study how it changes the visible color and brightness of stars. Without taking this phenomenon into account, all further reasoning about the structure of the stellar world cannot be correct.
Cosmic dust not only distorts distances in space, but also distorts our understanding of the stars. The phenomenon of star reddening, due to which stars appear to us comparatively colder than they actually are, is entirely the “merit” of cosmic dust.
Interstellar dust is not a medium of uniform density and consists of individual clouds, the average size of which is such that light travels from one edge to the other within ten years, that is, the size of these clouds is significantly greater than the average distance between stars.
It has long been known that in the cosmic space between the stars there are huge clouds of rarefied matter, some of which are gas and others are dust. Clouds of cosmic dust shine with the reflected light of those stars that are located near them.
However, the question of whether there is anything in common between these light dusty nebulae and the absorbing interstellar medium, which also consists of clouds, was not completely clear.
Some features of large clouds of dark dust, the so-called dark nebulae, are discovered due to the fact that they absorb the light of the stars behind them and form, as it were, gaps of complete blackness against a shining background.
As a result, it was proven that all the differences between “dark” and “light” dust nebulae consist only in the fact that the latter are located next to very bright stars, which illuminate them strongly enough for them to be visible, but the first ones are deprived of such “illumination”.
Thus, there was no significant difference between light and dark clouds of cosmic dust, and the question of how they appear to us depends solely on their random location in relation to bright stars.
Cosmic dust particles of matter in interstellar and interplanetary space. Light-absorbing condensations of photons are visible as dark spots in photographs. Milky Way. Attenuation of light due to the influence of K. p. - so-called. interstellar absorption, or extinction, is not the same for electromagnetic waves different lengths λ
, as a result of which reddening of stars is observed. In the visible region, extinction is approximately proportional to λ -1, in the near ultraviolet region it is almost independent of wavelength, but around 1400 Å there is an additional absorption maximum. Most of the extinction is due to light scattering rather than absorption. This follows from observations of reflection nebulae containing cosmic particles, visible around stars of spectral class B and some other stars bright enough to illuminate the dust. A comparison of the brightness of nebulae and the stars that illuminate them shows that the albedo of dust is high. The observed extinction and albedo lead to the conclusion that the crystal structure consists of dielectric particles with an admixture of metals with a size slightly less than 1 µm. The ultraviolet extinction maximum can be explained by the fact that inside the dust grains there are graphite flakes measuring about 0.05 × 0.05 × 0.01 µm. Due to the diffraction of light by a particle whose dimensions are comparable to the wavelength, light is scattered predominantly forward. Interstellar absorption often leads to polarization of light, which is explained by the anisotropy of the properties of dust grains (the elongated shape of dielectric particles or the anisotropy of the conductivity of graphite) and their ordered orientation in space. The latter is explained by the action of a weak interstellar field, which orients dust grains with their long axis perpendicular to the field line. Thus, by observing the polarized light of distant celestial bodies, one can judge the orientation of the field in interstellar space. The relative amount of dust is determined from the average absorption of light in the Galaxy plane - from 0.5 to several magnitudes per 1 kiloparsec in the visual region of the spectrum. The mass of dust makes up about 1% of the mass of interstellar matter. Dust, like gas, is distributed non-uniformly, forming clouds and denser formations - Globules. In globules, dust acts as a cooling factor, shielding the light of stars and emitting in the infrared the energy received by the dust grain from inelastic collisions with gas atoms. On the surface of the dust, atoms combine into molecules: the dust is a catalyst. S. B. Pikelner.
Big Soviet encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .
See what “Cosmic dust” is in other dictionaries:
Particles of condensed matter in interstellar and interplanetary space. According to modern concepts, cosmic dust consists of particles measuring approx. 1 µm with a graphite or silicate core. In the Galaxy, cosmic dust forms... ... Big Encyclopedic Dictionary
COSMIC DUST, very small particles of solid matter found in any part of the Universe, including meteorite dust and interstellar matter, capable of absorbing starlight and forming dark nebulae in galaxies. Spherical... ... Scientific and technical encyclopedic dictionary
COSMIC DUST- meteoric dust, as well as the smallest particles of matter that form dust and other nebulae in interstellar space... Big Polytechnic Encyclopedia
cosmic dust- Very small particles of solid matter present in outer space and falling to the Earth... Dictionary of Geography
Particles of condensed matter in interstellar and interplanetary space. By modern ideas, cosmic dust consists of particles about 1 micron in size with a core of graphite or silicate. In the Galaxy, cosmic dust forms... ... encyclopedic Dictionary
It is formed in space by particles ranging in size from several molecules to 0.1 mm. 40 kilotons of cosmic dust settle on planet Earth every year. Cosmic dust can also be distinguished by its astronomical position, for example: intergalactic dust, ... ... Wikipedia
cosmic dust- kosminės dulkės statusas T sritis fizika atitikmenys: engl. cosmic dust; interstellar dust; space dust vok. interstellarer Staub, m; kosmische Staubteilchen, m rus. cosmic dust, f; interstellar dust, f pranc. poussière cosmique, f; poussière… … Fizikos terminų žodynas
cosmic dust- kosminės dulkės statusas T sritis ekologija ir aplinkotyra apibrėžtis Atmosferoje susidarančios meteorinės dulkės. atitikmenys: engl. cosmic dust vok. kosmischer Staub, m rus. cosmic dust, f... Ekologijos terminų aiškinamasis žodynas
Particles condensed into va in interstellar and interplanetary space. According to modern According to the ideas, K. p. consists of particles measuring approx. 1 µm with a graphite or silicate core. In the Galaxy, the cosmos forms condensations of clouds and globules. Calls... ... Natural science. encyclopedic Dictionary
Particles of condensed matter in interstellar and interplanetary space. Consists of particles about 1 micron in size with a core of graphite or silicate, in the Galaxy it forms clouds that cause a weakening of the light emitted by stars and... ... Astronomical Dictionary
Books
- 99 secrets of astronomy, Serdtseva N.. 99 secrets of astronomy are hidden in this book. Open it and learn about how the Universe works, what cosmic dust is made of, and where black holes come from. . Funny and simple texts...