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The Commission on Tephrochronology, formed in 1961, comprises global researchers who characterize, map, and date tephra (volcanic ash) layers and use them stratigraphically as linking and dating tools in geological, palaeoenvironmental, and archaeological research. We review the commission’s history – its growth, leadership, and activities for 60 yrs that include hosting specialist meetings, symposia, and workshops, developing new analytical and dating methods and protocols, and supporting ECRs.

Kakioka Magnetic Observatory (KMO) has been monitoring the geomagnetic field and geoelectric field at Kakioka, Japan since 1913. It has promoted a variety of observations and research activity. In 1972, KMO developed Kakioka Automatic Standard Magnetometer (KASMMER) system, which enabled to provide the geomagnetic field data of the highest quality. Today, KMO operates a network of observatories in Japan and maintains the observations with the longest history in East Asia.

The term mascon either refers to the fact of a significant gravity anomaly within a celestial body, or to a modelling of these gravitational anomalies by localizing base functions. The localizing base functions which are labelled as mascons include point masses or surface elements based on the simple layer representation. In case of surface elements, the surface density is constant per mascon and each localizing base function is a two-dimensional step function on the sphere.

Lerwick Observatory in Shetland has recently celebrated its centenary. Measurements of atmospheric electricity where made at the site between 1925 and 1985. Instruments and equipment used for this are discussed and the value of the measurements obtained assessed. A major aspect of the atmospheric electricity work was explaining the dramatic changes which followed the nuclear weapons tests period. Although less well known, there are strong parallels with the discovery of the ozone hole.

The paper compares the historical context, organisation, personnel, conduct and scientific innovation of the voyages of HMS Challenger (1872–6) and SMS Gazelle (1874–6). Though the expeditions were in many regards similar, that of Challenger became famous and is regarded as marking the start of global marine science while the Gazelle voyage remains almost unknown. Why? A surprising factor may be what we now know as “Health and Safety” issues.