Geophysics

Comparing tidal forces during the March 2011 supermoon to normal tidal forces suggests that a perigee during full Moon does not cause earthquakes.

Mar 15, 2011 – Paul A. Heckert

Large magnitude earthquakes, such as Chile's 8.8 magnitude earthquake on February 27, 2010, can redistribute mass in Earth's crust enough to change the day length. Why?

Mar 3, 2010 – Paul A. Heckert

Earth and the other solid planets were liquid when they formed. Surface tension and gravity force fluids including planets, stars, and rain drops into a round spheres.

Jan 13, 2010 – Paul A. Heckert

The Aurora, often called the northern or southern lights, are caused by interactions between Earth's upper atmosphere and charged particles from the Sun.

Jul 24, 2009 – Paul A. Heckert

Earth's interior structure includes the crust, mantle, inner core, and outer core. The crust and mantle are rocky. The inner and outer cores are metallic.

May 9, 2009 – Paul A. Heckert