Researchers believe that the ice came from the protoplanetary disk.
Astronomers have discovered in the composition of the Acfer 094 meteorite that fell in Algeria, an unusual porous region. According to the researchers, they appeared after the evaporation of water ice, which fell in a meteorite from a protoplanetary disk rotating around the Sun, according to zn.ua.
A meteorite with a mass of 82 grams was found in Algeria in 1990, he refers to carbonaceous chondrites. Such objects are considered to be fragments of the most ancient and primitive asteroids and can be used to find them in ice or dust particles. In the study, the researchers analyzed two samples of a meteorite with a size of 25×25×30 micrometers.
It turned out that the samples are composed mainly of coarse-grained chondrules, inclusions, which are rich in calcium and aluminum, and various mineral fragments enclosed in a fine grained matrix which contains particles of amorphous and crystalline silicates of submicron and micrometer sizes, as well as sulphides of iron and Nickel.
In addition, scientists have found a number of porous areas with a scale of several tens of micrometers, which received the designation UPL-region (UltraPorous Lithology), bulk density which ranged from 1.6 to 1.9 grams per cubic centimeter, which is much less than the values of bulk density of the surrounding matrix, equal to 2.4 grams per cubic centimeter. In this case the matrix consists mainly of minerals such as phyllosilicates formed in the presence of water.
According to the researchers, initially, the pores were filled with water ice, which got there during the formation of the parent body. Then the ice is evaporated or melted under the action of heat.