Two pioneers of scientific ocean drilling, Walter Heinrich Munk and Gustaf Olaf Svante Arrhenius, passed away in February 2019. As colleagues at Scripps Institution of Oceanography, UC San Diego, Munk and Arrhenius both took part in the 1961 feasibility test for Project Mohole aboard the drilling platform CUSS I (Figure 1), which marked retrieval of the first cores of oceanic crust aided by the new invention of dynamic positioning.

Given, H., and R. Monroe. 2019. In memoriam: Walter Munk (1917–2019) and Gustaf Arrhenius (1922–2019). Oceanography 32(1):22–23, https://doi.org/10.5670/oceanog.2019.111.

This is an open access article made available under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution, and reproduction in any medium or format as long as users cite the materials appropriately, provide a link to the Creative Commons license, and indicate the changes that were made to the original content. Images, animations, videos, or other third-party material used in articles are included in the Creative Commons license unless indicated otherwise in a credit line to the material. If the material is not included in the article’s Creative Commons license, users will need to obtain permission directly from the license holder to reproduce the material.