There are quite a few fundamental constants. These are things like the speed of light (c) the charge on an electron (e), and the Planck constant (h). These constants are determined with some type of ...

Even teeny objects obey the law of gravity. A gold ball just 2 millimeters wide, with a mass of about 90 milligrams, is now the smallest object to have its gravitational pull measured. Observations of ...

It's fun to think about how we know stuff. For instance, the sun has a mass of about 2 x 10 30 kilograms. That is such an enormous mass that it's difficult to comprehend. And if it's so difficult for ...

Of the four fundamental forces, gravity is the one we’re most familiar with in our everyday lives, but perhaps surprisingly, it’s the weakest and hardest to measure here on Earth. Now, physicists in ...

Physicist Markus Aspelmeyer vividly remembers the day, nearly a decade ago, that a visitor to his lab declared the gravitational pull of his office chair too weak to measure. Measurable or not, this ...