Entangled atoms, separated in space, are giving scientists a powerful new way to measure the world with stunning precision.

The Hubble Space Telescope has been used to determine the mass of white dwarf star LAWD 37. It is "56 percent the mass of our ...

UK researchers shrink atomic fountain clock to 5 percent size, keeping ultra-precise time and making it portable for wider use.

Buoyancy corrections can become important when the density of the object being weighed is very different from the density of the masses employed for the calibration function. For example, this is true ...