But it may be the only defense, however partial it may be, that Kaczynski's attorneys have. FBI agents uncovered a trove of evidence in his Montana cabin, including virtual signed confessions and a signature completed bomb.
1 Whenever the Moon, Earth and Sun are aligned, the gravitational pull of the sun adds to that of the moon causing maximum tides.  Spring tides happen when the sun and moon are on the same side of the earth (New Moon) or when the sun and moon are on opposite sides of the earth (Full Moon).
In addition to the gravitational pulls of the Moon and Sun, the shape of the seafloor and local geography affect the tides. Try doing this project with data from a few different places, such as an island in the Pacific Ocean, a state that borders the Gulf of Mexico, and a state that borders the Pacific Ocean.