It was Aristarchus of Samos (310BC -230 BC), who ironically lived after Aristotle (384 BC – 322 BC), who was the first person in recorded history to come up with the idea of a heliocentric system, centuries before the Polish canon, physician and astronomer Nicolaus Copernicus (1473-1543) wrote and posthumously published his seminal treatise, De Revolutionibus Orbium Coelestium (On the Revolutions of the Heavenly Spheres). Aristarchus' idea of a heliocentric model of the cosmos, unfortunately, just didn't take with the ancient Greeks.

I went to the Scottish Games in Woodland, California last weekend, two young boys in tow.  They weren't remotely interested in Scottish women doing traditional dances and they were vaguely intrigued by why men wore kilts.

I have been teaching high school Physics for the past two years.  We demonstrated centripetal force by playing crack the whip in small groups in the gym.  They can feel that they would move in a straight line away from the circle if they let go of each others' hands. 

'Centrifugal force' may be the most incorrectly used term in popular media, so what is it?

For 75 years, some astronomers have believed that the universe contains unseen or ‘dark’ matter that must make up about five-sixths of the matter in the cosmos. The conventional theory of gravitation, based on Newton’s ideas and refined by Einstein 92 years ago, dark matter's existence would help explain the motion of galaxies and clusters of galaxies on the largest scales.