Scientists have uncovered evidence that points to a major mass extinction that wiped out many types of one‐celled algae 650 million years ago, near the end of the Precambrian era, according to the National Science Foundation ...

Modern data show that the Earth is wobbling much differently than earlier data indicated, according to a paper published in the September issue of Geophysical Research Letters. The paper examines flaws that exist in two ...

A simulation model developed to explore patterns of fracture enlargement within incipient limestone karst aquifers has been extended to turbulent flow. In contrast to the highly selective passage enlargement that occurs ...

The electrostatic probe experiment on Explorer 22, launched in October 1964, has permitted the concentration and temperature of the electrons at 1000 km to be observed on a global scale. The major features of the ionosphere ...

As early as 1866 P. Timoteo Bertelli began the study of the origin and early history of the mariner's compass. The results of his investigations were published in detail in 1893 in a paper entitled “Studi storici intorno ...

Thrust faulting in the Yukon‐Tanana Upland of east‐central Alaska has long been hypothesized, but few thrust faults have been definitely identified. In the Boundary area near the international border between Alaska and ...

Explorer 35 was injected into a selenocentric orbit on July 22, 1967. Analysis of measurements near periselene (800 km from the lunar surface) while the moon is within the geomagnetic tail suggests that the moon is not ...

In the summer and autumn of 1957 the author and his colleagues at the University of Iowa conducted 10 successful balloon‐launched rocket (rockoon) flights of Geiger‐Mueller tubes during two shipboard expeditions, one to ...

The Pinatubo eruptions of June 1991 introduced large plumes into the local stratosphere. On several occasions, volcanic gases and particles reached altitudes of about 30 km, quickly spreading to the west. Twenty days after ...

The early time interaction of an artificially injected lithium cloud with the solar wind is simulated with a one‐dimensional hybrid code. Simulation results indicate that the lithium cloud presents an obstacle to the solar ...