Harpoons
Harpoons
Number of harpoons in space by year [A chart with a red graph is drawn below.] [The y-axis.] 0 1 2 3 [The x-axis.] 1950 1960 1970 1980 1990 2000 2010 2020 [The graph is at zero until a sharp peak to 1 in 1970. The peak is labeled.] Apollo 12 rum incident [The graph then stays at 0 until 2004. Then it rises to 2 and stays there until today, continuing as a dotted line after 2014. The rise is labeled.] Rosetta comet mission launched carrying lander with harpoon tethers
In 2018, shortly after the line gets dotted, the number actually increased again., thanks to the RemoveDEBRIS satelite.

This comic is a graph of the number of harpoons in space over time. One would not expect that harpoons, which are associated with old technology, would be used in space, which is associated with high technology. Any occurrences are unexpected, and therefore interesting or funny.
The first peak states that a harpoon was in space during the Apollo 12 mission and various possible explanations have been put forward (See discussion section below). One of more widely accepted theories proposes that Harpoon brand of Jamaican rum made it aboard the Apollo 12 rocket. Despite a fair amount of research into the basis of the harpoon incident, there have been no credible or official sources to confirm the presence of any type of harpoon on board Apollo 12. As the presence of a harpoon on board would run counter to any official story, perhaps that's exactly why it would be considered an "incident".
The latter peak on this graph refers to the Rosetta unmanned spacecraft. As part of its mission, it carried a lander called Philae , which has two harpoon tethers to anchor itself to the comet 67P/Churyumov–Gerasimenko . Rosetta was launched in March 2004 (as shown in the graph) and was scheduled to encounter the comet in August 2014, making this a timely comic. Rosetta maneuvered to enter orbit on September 10, and ultimately the Philae lander touched down on the comet on 12 November 2014, although the harpoon system failed to deploy. Randall produced a live comic of the landing, updating 1446: Landing every 5 minutes with the latest progress. The Rosetta spacecraft also carries a disk micro-etched with 13,000 pages of text in 1200 languages donated by the Long Now foundation, mentioned in previous comics.
The title text compares the Philae lander's method of deploying its tethers to whaling , in which sailors would throw harpoons at a whale with the intent of killing the whale. It was important to throw hard so the harpoon would stick in the whale so it could not get away and would tow the whaling boat until it got tired and could be killed. Thus the title text implies that the spacecraft is sentient and needs a motivation to fire the harpoons hard enough to stay anchored to the comet; to this end it has been programmed to believe that its mission is to kill the comet. Evidently this motivation was not enough, as Philae ultimately failed to deploy its harpoons - it still managed to land, though.
Number of harpoons in space by year [A chart with a red graph is drawn below.] [The y-axis.] 0 1 2 3 [The x-axis.] 1950 1960 1970 1980 1990 2000 2010 2020 [The graph is at zero until a sharp peak to 1 in 1970. The peak is labeled.] Apollo 12 rum incident [The graph then stays at 0 until 2004. Then it rises to 2 and stays there until today, continuing as a dotted line after 2014. The rise is labeled.] Rosetta comet mission launched carrying lander with harpoon tethers
In 2018, shortly after the line gets dotted, the number actually increased again., thanks to the RemoveDEBRIS satelite.
