Sometime after midnight on February 8, 1969, a large, bright meteor entered Earth's atmosphere and broke into thousands of pieces, plummeted to the ground, and scattered over an area 50 miles long and 10 miles wide in the state of Chihuahua in Mexico. The first meteorite from this fall was found in the village of Pueblito de Allende. Altogether, roughly two tons of meteorite fragments were recovered, all of which bear the name Allende for the location of the first discovery.
第一段：掉了个陨石下来在mexico 大约撞了个50miles *10 miles的坑。大约2ton的碎片。
在Allende发现，所以叫做allende陨石。
Individual specimens of Allende are covered with a black, glassy crust that formed when their exteriors melted as they were slowed by Earth's atmosphere. When broken open, Allende stones are revealed to contain an assortment of small, distinctive objects, spherical or irregular in shape and embedded in a dark gray matrix (binding material), which were once constituents of the solar nebula-the interstellar cloud of gas and dust out of which our solar system was formed.
第二段：这个allende陨石的样本，被包裹着外层一层东东，然后broken open.
里面露出了成分，成分里面embedded in 嵌入一种dark gray matrix，这个物质是太阳系形成那会的星云物质。
The Allende meteorite is classified as a chondrite. Chondrites take their name from the Greek word chondros-meaning "seed" -an allusion to their appearance as rocks containing tiny seeds. These seeds are actually chondrules: millimeter-sized melted droplets of silicate material that were cooled into spheres of glass and crystal. A few chondrules contain grains that survived the melting event, so these enigmatic chondrules must have formed when compact masses of nebular dust were fused at high temperatures-approaching 1,700 degrees Celsius-and then cooled before these surviving grains could melt. Study of the textures of chondrules confirms that they cooled rather quickly, in times measured in minutes or hours, so the heating events that formed them must have been localized. It seems very unlikely that large portions of the nebula were heated to such extreme temperatures, and huge nebula areas could not possibly have lost heat so fast. Chondrules must have been melted in small pockets of the nebula that were able to lose heat rapidly. The origin of these peculiar glassy spheres remains an enigma.
第三段：这种enigmatic chondrules融化后是能够很快就冷却的。但是这么大的星云要冷却下来很难，所以这个C是一种袋状的方式lose heat rapidly。原因仍然是迷。
chondride---一种球类陨石。专业名词
an allusion to 一种reference
millimeter-sized 毫米大小
silicate material 硅酸盐材料
compact masses =dense
were fused at 被融化在 ==merge
Equally perplexing constituents of Allende are the refractory inclusions: irregular white masses that tend to be larger than chondrules. They are composed of minerals uncommon on Earth, all rich in calcium, aluminum, and titanium, the most refractory (resistant to melting) of the major elements in the nebula. The same minerals that occur in refractory inclusions are believed to be the earliest-formed substances to have condensed out of the solar nebula. However, studies of the textures of inclusions reveal that the order in which the minerals appeared in the inclusions varies from inclusion to inclusion, and often does not match the theoretical condensation sequence for those metals.
第四段：这段就是讲这个陨石还有一些耐火的成分令人费解。这些耐火成分组成主要是钙铝钛等。这些矿物质还被认为是星云形成那会有的。
condensed out 冷凝出来的
Chondrules and inclusions in Allende are held together by the chondrite matrix, a mixture offine-grained, mostly silicate minerals that also includes grains of iron metal and iron sulfide. At one time it was thought that these matrix grains might be pristine nebular dust, the sort of stuff from which chondrules and inclusions were made. However, detailed studies of the chondrite matrix suggest that much of it, too, has been formed by condensation or melting in the nebula, although minute amounts of surviving interstellar dust are mixed with the processed materials.
pristine = pure
C和includsions是和一种混合的xxxx什么硅酸盐材料混在一起的。
一度认为是原始星云的尘埃made的。
然鹅，研究表明尽管这些星尘尘埃是和材料混合的，但大多都是星云melting中形成的。
（太难翻了）
All these diverse constituents are aggregated together to form chondritic meteorites, like Allende, that have chemical compositions much like that of the Sun. To compare the compositions of a meteorite and the Sun, it is necessary that we use ratios of elements rather than simply the abundances of atoms. After all, the Sun has many more atoms of any element, say iron, than does a meteorite specimen, but the ratios of iron to silicon in the two kinds of matter might be comparable. The compositional similarity is striking. The major difference is that Allende is depleted in the most volatile elements, like hydrogen, carbon, oxygen, nitrogen, and the noble gases, relative to the Sun. These are the elements that tend to form gases even at very low temperatures. We might think of chondrites as samples of distilled Sun, a sort of solar sludge from which only gases have been removed. Since practically all the solar system's mass resides in the Sun, this similarity in chemistry means that chondrites have average solar system composition, except for the most volatile elements; they are truly lumps of nebular matter, probably similar in composition to the matter from which planets were assembled.
The major difference is that Allende is depleted in the most volatile elements, like hydrogen, carbon, oxygen, nitrogen, and the noble gases, relative to the Sun.
看不下去了。。
这种文章真的不是给人做的。。。，没沉淀，吃不下。
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