Where is the asteroids belt




















September 14, report. In their paper published in Science Advances , Sean Raymond and Andre Izidoro describe their theory and what they found when trying to model it. The asteroid belt sometimes referred to as the main asteroid belt orbits between Mars and Jupiter. It consists of asteroids and minor planets forming a disk around the sun. It also serves as a sort of dividing line between the inner rocky planets and outer gas giants.

Current theory suggests that the asteroid belt was once much more heavily populated, but the gravitational pull of Jupiter flung approximately 99 percent of its former material to other parts of the solar system or beyond. Astronomers also assumed that Jupiter's gravity prevented the material in the belt from coalescing into larger planets. In this new effort, the researchers propose a completely different explanation of the asteroid belt's origin—suggesting that the belt started out as an empty space and was subsequently filled by material flung from the inner and outer planets.

The researchers note that asteroids closer to the rocky planets called S-type asteroids tend to contain silicate, similar to the inner planets. By contrast, asteroids in the belt closer to the gas giants called C-type asteroids tend to contain more carbon, making them more like the gas giants.

This, the researchers note, suggests that the asteroids actually came from the planets as they were forming—excess material was essentially kicked away into the asteroid belt, where it remains today. To test their theory, the researchers created a model mimicking the early solar system, during which the asteroid belt starts out as empty.

Running the model forward, they report, showed that it was possible that material from the other planets could have made its way to the belt, resulting in the disk observed today. They plan to continue their research to see if they can find more evidence for their theory, or for the conventional view.

Explore further. Abstract The asteroid belt contains less than a thousandth of Earth's mass and is radially segregated, with S-types dominating the inner belt and C-types the outer belt.

It is generally assumed that the belt formed with far more mass and was later strongly depleted. We show that the present-day asteroid belt is consistent with having formed empty, without any planetesimals between Mars and Jupiter's present-day orbits.

This is consistent with models in which drifting dust is concentrated into an isolated annulus of terrestrial planetesimals. Gravitational scattering during terrestrial planet formation causes radial spreading, transporting planetesimals from inside 1 to 1.

Several times the total current mass in S-types is implanted, with a preference for the inner main belt. The current known asteroid count is:. Most of this ancient space rubble can be found orbiting the Sun between Mars and Jupiter within the main asteroid belt. Asteroids range in size from Vesta — the largest at about miles kilometers in diameter — to bodies that are less than 33 feet 10 meters across. The total mass of all the asteroids combined is less than that of Earth's Moon.

Go farther. Key Science Targets. The total mass of all the asteroids in the main asteroid belt combined is less than that of Earth's Moon. Asteroids are small, rocky objects that orbit the Sun. There are hundreds of thousands of asteroids in the asteroid belt, but almost half of the entire mass is made up of just four objects. These objects are the dwarf planet Ceres, and three other asteroids called Vesta, Pallas and Hygiea.

The diameters of Vesta, Pallas and Hygiea are over km and Ceres is even bigger at km diameter. Apart from these four objects, the remaining objects in the asteroid belt range in size from small rocks right down to dust particles. The asteroid belt is between the planets Mars and Jupiter. It is located about 2. That is somewhere between million km away. At the same time, studies of white dwarfs, sun-like stars at the end of their lifetimes, show signatures of rocky material falling onto their surface that suggest such belts are common around dying systems.

Most of the asteroids in the Main Belt are made of rock and stone, but a small portion of them contain iron and nickel metals. The remaining asteroids are made up of a mix of these, along with carbon-rich materials. Some of the more distant asteroids tend to contain more ices. Although they aren't large enough to maintain an atmosphere, but there is evidence that some asteroids contain water. Some asteroids are large, solid bodies — there are more than 16 in the belt with a diameter greater than miles km.

The largest asteroids, Vesta , Pallas and Hygiea, are miles km long and bigger. The region also contains the dwarf planet Ceres. At miles km in diameter, or about a quarter of the size of our moon, Ceres is round yet is considered too small to be a full-fledged planet. However, it makes up approximately a third of the mass of the asteroid belt.

Other asteroids are piles of rubble held together by gravity. Most asteroids aren't quite massive enough to have achieved a spherical shape and instead are irregular, often resembling a lumpy potato. The asteroid Kleopatra resembles a dog bone. Asteroids are classified into several types based on their chemical composition and their reflectivity, or albedo.

Dawn reached Vesta in and remained there for over a year before traveling on to reach Ceres in



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