DeepEarthScience

On a cold winter day, 21 November 1934, professor Vening Meinesz turned on his pendulum apparatus. Just a few minutes ago, the submarine K-XVIII dived to a depth of 30 meters [1]. A t these depths, t he motion of the surface waves was dampened such that it did not influence the delicate measurements done by the professor. This particular observation would mark the 500th measurement, observing the tiniest changes in the Earth's gravity field. This new gravity dataset would reveal many new mysteries of our home planet and would be the life’s work of Vening Meinesz. It is all documented in scientific publications of four volumes called  Gravity Expeditions at Sea , followed by a fifth volume with gravity observations done by his students. Along these expeditions, the professor had brought his specially designed pendulum apparatus, or folklorised by the sailors on board the many submarines: Het Gouden Kalf  (the Golden Calf). The pendulum apparatus of Vening Meinesz, also kn...

Last week, I could cross something from my bucket list. As the title already hints at, I was onboard a submarine. Ok, the submarine was not submersed in the ocean, it wasn't even in the water, but it was a real submarine, the Hr. Ms. Tonijn ("Tuna"). You can visit this submarine in Den Helder at the museum of the Dutch Navy. However, our project group (Vening Meinesz, I wrote about this) and I were guided by one of the officers that had served on board the Hr. Ms. Tonijn, who gave us an incredible tour inside the submarine. The Hr. Ms. Tonijn was in service between 1966 and 1991 for the Dutch Navy, so it is a more modern version than the Hr. Ms. K18, but some technical details, as we will see, are almost similar. This three cylinder submarine was designed by ir. M. F. Gunning with the top cylinder, being the living quarters and visitable in the museum. The bottom two cylinders contained the massive diesel and electric motors, as well as the chemical battery compartme...