May 3rd, 2008

aye aye captain

Krakatau

One of the books I bought on to my last trip to Sydney was Simon Winchester's Krakatoa - The Day The World Exploded - 27th August 1883.

Enthralling read. I never knew, for example, that 3 locals had been on the island the day the nearby beach first started erupting. They had to swim to their boat, the ground level was dropping that fast.

And a horrifying read too, after the first half of the book's diversions into Dutch history, the rise of tectonic theory, and so on, and got onto the actual 1883 eruption.

Collapse )
(melanistic) Barn Owl

shrimpoluminescence

I checked the tags, so hopefully this hasn't been posted here before.
Snapping/Pistol/Alpheid Shrimp.

"The shrimp snaps a specialized claw shut to create a cavitation wave that generates acoustic pressures of up to 80 kPa at a distance of 4 cm from the claw. The pressure wave is strong enough to kill small fish. ... The duration of the click is less than 1 millisecond. ... The snap can also produce sonoluminescence from a collapsing cavitation bubble. As it collapses, the cavitation bubble reaches temperatures of over 5000 K. The light is of lower intensity than the light produced by typical sonoluminescence and is not visible to the naked eye. ... It is the first known instance of an animal producing light by this effect."
Collapse )