[Stevie Bain (OP)]

Shireen would like to know:

When a missile lands in the ocean, what happens to sea life in the vicinity?

Can you help?

[chris]

I would say that it depends upon what happens to the missile. If it merely "splashes down", then nothing. But if the missile explodes then it will produce a shock wave that will be transmitted through the water. The pressure changes are likely to cause lethal damage to things that are close by, from microbes-scale right up to the macro scale. At greater distances injuries are still possible: whales have been discovered with ear injuries secondary to offshore seismic tests.

[RD]

... The pressure changes are likely to cause lethal damage to things that are close by, from microbes-scale right up to the macro scale.

Apparently some microbes can withstand phenomenal forces  : 400,000 x g .... http://www.pnas.org/content/108/19/7997.full

[chris]

... The pressure changes are likely to cause lethal damage to things that are close by, from microbes-scale right up to the macro scale.

Apparently some microbes can withstand phenomenal forces  : 400,000 x g .... http://www.pnas.org/content/108/19/7997.full

You're quite right, @RD and that is sometimes cited as evidence that the theory of panspermia is at least plausible. However, we should be clear that not all forms of microbial life are equivalently robust and some more fragile species will certainly succumb under the conditions of a nearby explosion.