The work so far has thrown up a number of interesting results, the most surprising of which is that most of the dust from the comet Wild 2 shows the presence of aluminum-rich melt droplets. It’s very hard to understand how these compounds could have formed in a comet that had only ever experienced the icy conditions of space, since they require temperatures of more than 1200°C to do so. Since comets are thought to be frozen rocks that date back to the birth of the solar system, this has come as a bit of a surprise, to say the least. The results seem to indicate that the standard model of comet
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