In a brief story published in Danish on, Aske L. Sørensen and Tais W. Dahl explain one of the consequences of their latest EPSL paper: Earth was spinning faster 500 million years ago.

Photo: The Alum shale is exposed all over Scandinavia, here at Andrarum in Southern Scania. Credit: Niels Schovsbo, GEUS.

The scientific paper entitled “Astronomically forced climate change in the Late Cambrian” documents Milankovitch-cycles in two drill cores through the Alum shale formation. A precise determination of the obliquity period of 31.4±1.2 kyr was derived from the robust 405 ky eccentricity cycles, which translates into a day length of 21 hr 47 min – and a precision of only 17 min.

The press release was soon picked up of Danish Broadcasting Corporation (DR) and TV2 news (12/10-20 at 17:45).