The European Space Agency has published the first map of the gravitational field of our planet, built according to the GOCE satellite. Thanks to the uniqueness of the satellite, the collected data is extremely accurate, and the map itself will help oceanographers and climatologists to give more reasoned answers to global questions about the life of the Earth.

The GOCE satellite (full name - "Research of the gravitational field and steady ocean currents"), developed by the European Space Agency, was launched from the Russian Plesetsk cosmodrome on March 17, 2009. The aim of the project is to map the gravitational field of the globe with unprecedented accuracy and resolution. With unprecedented, because GOCE is not the only such project. Before him, the German research satellite CHAMP was launched into space (the project started in 2000), as well as a tandem of two GRACE satellites (2002).

The beginner determines the differences in the strength of the Earth's gravitational field to the nearest centimeter. To surpass "colleagues" in the reliability of the received data GOCE helps a number of technical tricks that give the satellite the ability to fly at a very low altitude - 254.9 km. This is the lowest orbit that has ever been in a long time research satellites.

The GOCE developers have achieved the effect when the sensors of the apparatus for measuring the Earth's gravity are, as it were, in free fall. The main know-how is the ion engine, which compensates for the atmospheric braking that is inevitable at a specified altitude and periodically raises the satellite's orbit. The arrow-shaped form of the European messenger and his "fins" also play a role. Thanks to all this, the satellite is an extremely sensitive measuring device, opening up new, previously inaccessible opportunities for researchers.

“The gravitational field has been studied for a very long time, and in recent times Great progress is being made in this area thanks to the use of new high-precision satellite systems, - explains Valentin Mikhailov, head of the laboratory of mathematical geophysics at the Institute of Physics of the Earth, Russian Academy of Sciences. "The advantage of studying the Earth's gravitational field from Earth orbit is the almost uniform coverage of oceans and land."

Due to its "advancement" GOCE has demonstrated an excellent ability to capture tiny nuances in the changing force of gravity. A map compiled from the data obtained from him shows that this force is far from uniform. In particular, positive gravitational anomalies are marked in red on the model built according to the GOCE satellite data for November-December 2009, and negative ones are marked in blue.

“However, these anomalies should not be taken as something out of the ordinary, the existence of global anomalies has long been known,” adds Mr. Mikhailov. - The GOCE satellite will significantly improve our knowledge of the fine structure of the gravitational field, which is necessary, for example, to model the dynamics of the ocean and the interaction of the World Ocean with the atmosphere. This is important for predicting climate change and natural disasters like the El Niño phenomenon, caused by the movement of large volumes of heated water into pacific ocean».

The authors of the project themselves claim that the data obtained from the GOCE satellite will find numerous applications and can be useful not only for a better understanding of nature ocean currents and determining their speed, but also, for example, to detect dangerous volcanic regions.
http://www.rbcdaily.ru/2010/07/01/cnews/491111

ESA: The most detailed map of Earth's gravity field ever realized

Physorg.com: GOCE delivering data for best gravity map ever (w/ Video)

For two years of work, the European satellite GOCE (Gravity Field and Steady-State Ocean Circulation Explorer - a researcher of the gravitational field and steady ocean currents), measuring the Earth's attraction, has collected enough data to compile a gravitational map of unprecedented accuracy, Membrane reports.

The GOCE team spoke about the results of his work at a conference in Munich.

Launched in 2009, the device has six accelerometers that are a hundred times more sensitive than those of...

Geophysicists presented preliminary maps created from data collected spacecraft European Space Agency (ESA) GOCE. The maps were made public at the annual meeting of the American Geophysical Union.

Since the shape of the Earth is not a sphere, the gravitational attraction in some regions can be quite different from the attraction in others. Based on the data on these differences, the scientists colored the map: regions marked in red, where the acceleration of free fall is greater than 9 ...

Scientists Russian Academy Sciences (RAS) are investigating a mysterious artifact created by someone in prehistoric times.

Pantry sensation

And what did you find in it? An ordinary cracked stone, - the press secretary of the rector of Moscow State University Olesya Viktorovna indifferently glanced at the stone slab, which is stored in the pantry of the university.

The photographer and I were in awe. Because we finally saw “that very stone map” that we were told about. And they assured her that she was supposedly 65 ...

The American and Japanese space agencies have published the most accurate (second in a row) to date topographic map Earth. This was reported in a press release on the NASA website. The first version of the same map was published in June 2009.

As part of new version data obtained after the analysis of 260,000 stereo images made by the Terra apparatus were added to the map. As a result, the resolution of the map has been significantly increased. The map is available for free access on the Internet...

Physicists have conducted the most accurate experiment to date to measure the gravitational time dilation predicted by Einstein's theory of relativity.

The essence of the experiment was as follows. Cesium atoms, cooled almost to absolute zero, were “thrown” up in a special chamber with the help of a laser, after which, under the influence of gravity, they began to move in an arc.

At some point in time, a laser pulse brought the particles into a superposition of two states...

Gravitational lenses, discovered by astronomers about 30 years ago, are one of the most amazing phenomena in the universe. They became not only the most convincing proof of the truth of Einstein's theory of relativity, but also indispensable assistants to astronomers in the search for answers to many questions about the structure and evolution of the universe.

Like the mirages that travelers encounter in the desert, there are mirages in space. They occur when light from distant objects is deflected...

Science is getting closer to confirmation biblical truths. From the school bench we know: our planet has the shape of a ball elongated at the poles, consists of a mantle and a core, and several layers of the atmosphere hovers above its surface.

Since time immemorial, it has been rotating around its axis and around the Sun, and this mechanism, wound up by nature itself, will never stop. At least, that's how it seems to us.

Our interlocutor, a professor, Doctor of Physical and Mathematical Sciences, a leading scientific ...

Dimensions in an expanding world

It is not easy to build a map of the world, the objects of which are in constant motion - at the same time they move relative to each other, and scatter in different sides. “Let's not forget that at interstellar distances the concept of simultaneity is far from obvious,” Paul Anderson wrote in one of his stories about Rogue Traders, and this circumstance greatly complicates the life of space explorers. Here, for example, how to determine the distance to some distant ...

The European Space Agency (ESA) has released the first results of studies of the Earth's gravitational field, conducted using the GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) satellite.

The European Space Agency (ESA) has released the first results of studies of the Earth's gravitational field, carried out using the GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) satellite.

A research team working with the European satellite GOCE (Gravity Field and Circulation Ocean Current Investigator) has shed light on what our Earth looks like from a gravitational point of view.

New computer model demonstrates the unevenness of gravity on the surface of our planet: the Earth in this image does not look like a neat globe familiar to all of us.

A new geoid model was presented at the Fourth International Scientific Forum, which was held in Technical University Munich (Germany). Representatives of the European space community said that they now have the most accurate map of the distribution of the planet's gravitational flows.

Scientists have used data collected by the space probe to show how gravity affects the entire area of ​​​​our planet. The device showed how the oceans move and how they redistribute solar heat throughout the globe of the Earth.

The abstract model in the image is an illustration of the uneven force of gravity acting on the surface of our planet. Yellow indicates areas where gravity is higher, and blue indicates areas that are lower than the global average.

GOCE also helped scientists understand that the quakes in Japan last month and Chile last year were due to huge plate masses moving suddenly.

Scientists said the new data helped shed light on what the "level" of the Earth's surface looks like. A boat off the coast of Europe can stand 180 meters higher than a boat in the middle indian ocean, although both of these points are at the same time at the same land level.

It is obvious how the gravitational trick plays out on Earth, since our planet is not a perfect sphere, and its mass is distributed unevenly, the scientists explain.

The GOCE satellite was launched in March 2009. Today space probe located in a very low polar orbit with an altitude of only 255 km. Other research satellites do not fly so low, experts say.

GOCE is equipped with three pairs of platinum sensors as part of its main scientific instrument, the gradiometer, which measures microscopic changes in acceleration force.

This acceleration allows GOCE to map the almost imperceptible fluctuations in the force of gravity acting on the surface of our planet - from the highest mountain ranges to the deepest ocean trenches.

The geoid is the most important concept in modern geodesy. He is geometric body, repeating the shape of the Earth, but reflecting the distribution of the potential of gravity on the planet. Usually the geoid approximately coincides with the average water level of the World Ocean and conditionally continues over the continents.

"We have received completely new information, in particular in areas such as the Himalayas, the Andes and Antarctica," Dr. Rune Floberghagen, head of the European Space Agency's GOCE mission, told the BBC.

The team of scientists said that GOCE probably has enough onboard fuel and will be able to fly until 2014.

According to Liner Rummel, a professor at the University of Munich, the first practical results from the work of the European gravitational satellite can be obtained in about a year. “GOCE gravity data will help develop a more advanced earthquake prediction model. Since earthquakes are caused by tectonic movements under the ocean, these movements cannot be seen directly from space, although they can be studied from gravity data,” the scientist noted.

The most accurate gravitational map of the Moon to date has been compiled.

If you decide to spend money to put something in the orbit of the Moon, it will most likely be chock-full of scientific instruments. But NASA was original - they sent not one, but two ships there, but with a single instrument.

Despite external lightness, the project GRAIL turned out to be phenomenally successful, because it made it possible to draw up the most accurate geological map of our neighbor. It is now clearly seen that this world was shaped by a combination of meteor impacts (some of which probably pierced the Moon to the mantle) and stretch marks, indicating the expansion of the body at the beginning of its history.

The GRAIL project is modeled after the GRACE satellites that explore the Earth. A single instrument tracks the distance between the paired vehicles, which varies due to gravity. Since there is no significant atmosphere on the Moon, and the force of gravity is very weak, the GRAIL vehicles were able to descend to an average height of 55 km, resulting in a map scale that was almost three times better than previous efforts.

The first stage of the project started in March this year. and ended in May. The probes were able to distinguish formations about 13 km in size. More than 99.99% of possible data were received, taking into account the resolution of the equipment.

What we see on the moon is there - that's the beauty of it. The authors of one of three articles about the project, published in the journal Science, note that more than 98% of local changes in gravitational attraction are a product of surface topography. In other words, the craters and ridges that we see on the surface of the Moon produce the bulk of the signals received by GRAIL. There is nothing similar in other objects studied by us. Earth, Venus, Mars, Mercury have great internal variability, which, as a rule, is the result of tectonic processes.

Although the moon has survived several volcanic eruptions, most of the relief details are formed by meteorite impacts. Look at the maps: the collision sites are very dense in a central region (where the material is compressed and heated) surrounded by low-density fractured material. Moreover, there were so many blows that the bark is spongy and relatively homogeneous. That is, meteorites in a sense played the role of a food processor. By the way, the GRAIL data suggests that the lunar crust may be thinner than predicted.

This moment is very important. “The strongest impacts could pierce through the thin crust and reach the mantle,” the authors write. Modeling suggests that in two zones of influence the thickness of the inner part tends to zero (the Sea of ​​Moscow and the Sea of ​​Crises), while in three others it is close to zero (the Humboldt Sea, Apollo and Poincaré craters).

One of the articles explains why there were sometimes no signals from obvious terrain details. These are the same 2% that were missing a few paragraphs above and which fall on internal, hidden reasons. Among them, the most noticeable are long lines, some of which stretch for almost a thousand kilometers. These formations are relatively deep: they start about 5 km from the surface and go down at least 70 km. These are very ancient structures, as they are interrupted by large impact craters that appeared at dawn lunar history.

The authors see them as an analog of terrestrial group dikes, that is, places in which tectonic faults let molten material into the crust from a great depth. Although there has never been much plate tectonics on the Moon, it is believed that the heating from the impact that created the Moon led to the formation of an ocean of magma under the lunar crust. That's where the molten material could come from. But what caused the break?

The researchers draw attention to the fact that in models of the early Moon, its layered structure consists of a relatively cool interior, a molten ocean, and a cooled crust. This structure was supposed to heat the interior at the same time as cooling the outer shell, which led to the expansion of the moon. It is assumed that in the first billion years the radius of our neighbor increased by 0.6-4.9 km, after which it decreased again. According to the authors, this could be enough for the appearance of huge cracks in the crust, which were filled with magma.

In general, the GRAIL data can tell a lot about the primitive history of the Moon and impose restrictions on models of its formation. In addition, they hint at conditions in the inner solar system shortly after its formation, shedding light on the collisions that all bodies have experienced, even though time may have obscured their traces. Not bad for a single tool?

The results of the study are published in the journal

To date, the most accurate model of the Earth's gravitational field has been compiled, which will help in the study of earthquakes, tides, ocean circulation and air masses. This was made possible thanks to the European GOCE satellite with a unique design, located in a special orbit.

Rice. 3.2.1

After two years of work in orbit of the GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) satellite, the European Space Agency has released the world's most complete map of the Earth's gravity. The collected data was enough to provide scientists with access to the most accurate geoid to date - a model of the Earth, which should help to understand the features of the earth's functioning - climate, ocean and air currents, and movements of lithospheric plates.

The geoid is the surface of an ideal global ocean in the absence of tides and currents. Its shape is determined only by gravity.

Fragment new card(fig.3.2.2). The strongest gravity is in areas painted yellow, the weakest - in the blue areas. The shape of the geoid is deliberately strengthened - for greater clarity, the differences in heights are multiplied by 10 thousand times.

Knowing the exact shape of the geoid is important for geodesy - it is used to measure heights in the world (illustration by EPA, ESA/HPF/DLR).

Rice. 3.2.2

What's even more interesting: GOCE sees deviations in gravity in high detail, which allows you to notice tectonic faults, calculate the distribution of masses in the thickness of mountain ranges and observe other similar structural features of the Earth hidden from view. By deciphering the information from GOCE, scientists can see the movement of magma in the depths beneath volcanoes or capture features in the movement and interaction of continental plates.

The GOCE satellite was launched in March 2009. To date, he has spent more than 12 months in the operational data collection mode.

GOCE has already become an exceptional phenomenon in space and in the study of life on the Earth. Its gradiometer, which consists of six highly sensitive gravity-based accelerometers, is unique in Earth orbit.

The launch of the LISA (Laser Interferometer Space Antenna) space interferometer with a shoulder length of 5 million kilometers is scheduled for the middle of the next decade, this is a joint project between NASA and the European Space Agency. The sensitivity of this observatory will be hundreds of times higher than the capabilities of ground-based instruments. It is primarily designed to search for low-frequency (10-4-10-1 Hz) gravitational waves that cannot be caught on the Earth's surface due to atmospheric and seismic interference. Such waves are emitted by binary star systems, quite typical inhabitants of the Cosmos. LISA will also be able to detect gravitational waves generated when ordinary stars are swallowed up by black holes. But for the detection of relic gravitational waves that carry information about the state of matter in the first moments after the Big Bang, more advanced space instruments are most likely required. Such an installation, the Big Bang Observer, is currently being discussed, but it is unlikely that it will be created and launched earlier than in 30-40 years.

Gravitational anomalies

Gravitational anomaly is a general term that is used in cases where unusual indicators of the gravitational field or the gravitational characteristics of an object are observed. The term is also used when mathematical model gravitational theory contradicts another theory or the physical nature of the gravitational interaction.

When applied to the shapes and gravitational properties of celestial bodies, gravitational anomalies are usually expressed as a change in the gravitational acceleration in their vicinity, which may indicate the presence of minerals with a high density value or, conversely, the presence of large voids in the rocks. In the latter case, there are sometimes anomalous phenomena, like water flowing "up" on an inclined plane or wheeled vehicles moving "up". Ground manifestations of anomalies also include the deviation of the plumb line from the vertical position and the change in the speed of the pendulum clock. In cases associated with ore deposits, geomagnetic anomalies are also often observed, which are associated with various phenomena in the Earth's atmosphere and in the ionosphere.

Unlike such massive celestial bodies as the Earth, lighter celestial bodies have great relative values gravitational anomalies, which does not allow describing their gravitational potential by harmonic functions. In the case of the Earth, the gravitational potential of the surface, or geoid, is described precisely on the basis of mathematical theories using harmonic functions. The gravitational anomalies of the Moon have their own name - mascons.

With the beginning of an era space flights the study of the geopotential of the Earth is carried out mainly by studying the change in position artificial satellites Lands that are equipped with accelerometers. It is assumed that the appearance of gravitational anomalies can also be associated with the danger of earthquakes and volcanic eruptions.

In cosmology, unusual accumulations of the mass of matter, which manifest themselves in the form of gravitational lenses and an anomalous distribution of the velocities of objects in their vicinity. In such cases, as in the case of the "Great Attractor", both of these phenomena are observed. Also, usually the term gravitational anomaly is used in connection with accumulations of dark matter or the hidden mass of the Universe.

Rice. 3.2.3 - Gravitational anomalies of the earth (according to NASA GRACE -- Gravity Recovery And Climate Change)