Friday, 10 June 2011

Is there anybody out there?

Different meteorites contain different stuff. Not a revelation, and I've probably mentioned this before. Most that are found are iron, but most that fall are stony meteorites - chondrites. There are a wide range of chondrites, but possibly the most important ones, for a very specific reason, are the carbonaceous ones.

Carbonaceous chondrites have organic content  - and again there is quite a range. They are not common, and the challenge is to find as wide a range as possible - to try to form as complete a picture as possible. This will then provide a fair estimation of the 'starting point' of organic matter at the time the solar system, and Earth, were formed some 4.55 billion years ago. A line of thinking being researched now is common-source hypothesis, which suggests almost all organics are derived from a single source and that the early diversity stems from exposure to hydrothermal activity in their host bodies.

One of the biggest questions science faces is the origin of life. Evolution provides a comprehensive answer to the diversity and complexity of life, but so far the very beginnings are still to be revealed. It's a hot topic and there are many hypotheses currently being explored, but one that has come to prominence in recent years has been the idea that life, or at least the means to it, came to Earth from space. Not in a shiny silver rocket or flying saucer, but by way of a meteorite. This possibility is looking increasingly likely.

It follows that if the vast majority of organics in our solar system come from a solitary source that was being spread at the time of formation, the other planets were likely to have received their share. And, further to that, had the common source been outwith the system to begin with, surely the same material would be more widespread than just our solar system; would probably be elsewhere. Out there. Quick! To Area 51! Or whatever it is.

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