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If the world exploded, what proportion of the rocks floating in space would have evidence of life? (continued)
Hillary Shaw
Newport, Shropshire, UK
So, you have somehow exploded the planet with enough force to scatter the debris into a second asteroid belt. The volatiles like water will have all dispersed. As any terrestrial fossils are largely in the top, say, 600 metres of crust, or 0.01 per cent of Earth’s radius, almost all these asteroids will be fossil-free.
A lump of coal or chalk, or even concrete or glass, wouldn’t necessarily indicate former life to an alien. They could surmise an abiogenic origin for all of these. Most actual fossils would be pulverised in the explosion. However, if the alien were lucky, they would find fragments of materials like plastic, alloy steels and other metals that are harder to conjecture a natural origin for.
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A lump of coal or chalk, or even concrete or glass, wouldn’t necessarily indicate signs of former life to an alien
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The metal fragments might be bright and reflective, so with a good telescope, these would stand out. Ironically, they would see evidence of us, but not of other life forms.
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