Rosetta sent down a lander named Philae to set down on the surface, using harpoons to anchor itself, but instead the lander bounced, unable to penetrate the tougher-than-expected material.
He then called for his harpoon, had the wooden stock drawn from it, and then had the iron part placed in the coffin along with one of the paddles of his boat.
The stinging cells in the tentacles release a harpoon of venom that stabs their prey and injects venom which paralyzes them and they can begin to consume that prey.
" Aye, breach your last to the sun, Moby Dick! " cried Ahab, " thy hour and thy harpoon are at hand! —Down! down all of ye, but one man at the fore. The boats! —stand by! "