Gravity is certainly the most familiar force out of the four fundamental forces we know. We can see and feel its effects on us and on our surroundings every day. Gravity keeps us grounded - literally. Nevertheless there are still many open questions regarding gravitation and its nature - for example, that it is incredibly weak compared to the strength of the other three fundamental forces.

Physicist and broadcaster Jim Al-Khalili addresses some of the many fascinating aspects of gravity in a highly regarded documentary. You can have a look at another of his television specials about the science of gravity here.

The variations in acceleration due to gravitation on Earth can have unexpected effects - even influencing timekeeping! In a magazine article, astrophysicist and author Ethan Siegel tells the story of why timekeeping first failed in the Americas and the physics behind it - an interesting and also funny episode in history.

The recent first detections of gravitational waves opened up a new field in observational astronomy. It also showed that there are still areas in this field of science open for discoveries to be made. The observations resulted in the 2017 Nobel Prize in Physics awarded to three of the major contributors to these discoveries. The New York Times article Learning from Gravitational Waves tells a little bit about the LIGO (Laser Interferometer Gravitational-Wave Observatory) facility, its history, and why this research is important.

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