Václav Jan Láska (24 August 1862 – 27 July 1943) was a Czechgeodesist,astronomer,geophysicist andmathematician. He was based mainly atCharles University, and was the founding director (1920–1933) of the State Institute of Geophysics, which later became theInstitute of Geophysics of the Czech Academy of Sciences.
Láska was born on 24 August 1862 inPrague. He graduated from theFaculty of Arts, Charles University in Prague (that time called Charles-Ferdinand University). After his studies, he worked as an astronomer at theClementinum observatory, but left due to the low salary and began to studygeodesy. He graduated from geodesy at theCzech Technical University in Prague in 1890 and remained at the university as a professor of cartography, higher geodesy andphotogrammetry. By 1895, he was offered the position of professor of higher geodesy and astronomy at theUniversity of Lviv, which he accepted. Here he established contacts with a number of foreign notable scientists who gathered in his house. During this period, he primarily devoted himself toseismology and was cited in many textbooks on geophysics and earthquake science.[1][2]
He returned to Prague in 1911 and became professor of Applied Mathematics at theFaculty of Arts, Charles University. He died on 27 July 1943 inŘevnice.[1] He is buried at theOlšany Cemetery in Prague.[2]
This empirical rule is one way how to approximate the distance from an earthquake's epicenter. The rule is most fitting for distance in the range of 2−10 Mm (thousand km).The epicentral distance in thousands of km is roughly equal to the difference between arrival times ofS andP waves in minutes minus 1.
