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Karl Terzaghi, reached out to Laurits Bjerrum in 1954, impressed by his paper on Norwegian quick clays' stability. At 36, Bjerrum, already a PhD and NGI director, emphasized practical research integration, influenced by centers like Imperial College London. He advocated for Soil Mechanics in civil engineering education and founded its chair in 1960. Bjerrum left a lasting legacy, earning international acclaim for his NGI work and collaborations with geotechnicals like Terzaghi and Casagrande.

In December 2021 the agonic line crossed the Royal Observatory of Madrid on its westward drift. The previous cross of the agonic line, drifting eastward, is not accurately dated because declination measurements of that time are scarce. After collecting the data made in the Iberian Peninsula over the last 500 years and reducing them to the ROM coordinates, a geomagnetic declination curve has been generated. As a result, the previous cross of the agonic line has been dated around the year 1652.

1. The DC powered service of the Berlin suburban railways disturbed the observations in Potsdam and Seddin. 2. A suitable location for the establishment of a new observatory was found near by the small town of Niemegk. 3. The “Adolf-Schmidt-Observatorium für Erdmagnetismus Niemegk” was officially opened on 23 July 1930, Adolf Schmidt’s 70^th. 4. The observations started on 1 January 1932. 5. The Niemegk measurement series span over 92 years only interrupted at the end of World War II.

The meteorite "Veramin" fell in Persia ca. 1880. In the records, there are ambiguities about the event and we therefore scrutinized the available sources. The current official name, coined by meteoricist A. Brezina, is not supported by Iranian documents. A key document is a rediscovered label with the main mass of the meteorite. The indicated place of the event, probably occurring in February–April 1880, is Booghin of in the historical Zarand district, 100 km NW from Veramin (Varamin).

Over the past decade, a vast ancient Lake has been discovered in the central region of Iran, known as the Paleo Mega Lake of Rey. This paper aims to meticulously examine the provided data while accurately pinpointing to this lake. Additionally, significant data related to periods when the lake was filled with water has been acquired. Consequently, there is no longer any room for uncertainty regarding the presence of the lake during the era when humans resided in the territory of Iran.

The explanation of thunder and lightning in encyclopedias from ancinet times to WIKIPEDIA is described and discussed.

Long-term series of historical observations in Latvia of mesospheric clouds are digitized. Observational data are freely available to researchers. Observation sites, methodology and technical support are described. A brief overview of mesospheric cloud observation statistics 1957–1983.