IN recent issues of NATURE and the Philosophical Magazine, Profs. Larmor and Fitzgerald and Lord Kelvin have expressed themselves as if satisfied that the negative result of the celebrated Michelson ...

Earth rotation and polar motion prediction encompass the estimation and forecasting of key parameters that describe the rotational behaviour of our planet. These predictions are pivotal for ...

On Tuesday, February 19th, the Moon will reach perigee, its closest point of approach to planet Earth. On that same day, just a few hours earlier, its surface will be 100% illuminated by the Sun, ...

Mars has just entered retrograde, suddenly reversing its course across the sky. As of October 30, Mars stopped moving eastwards through the night sky and began crawling its way westwards through the ...