Newton's gravitational constant, often denoted as G, is a fundamental physical constant that quantifies the strength of gravitational attraction between two masses. Its value is approximately 6.674 × 10⁻¹¹ N(m/kg)². This constant is crucial for calculating the gravitational force between objects, such as planets, stars, and other celestial bodies, according to Newton's law of universal gravitation. G plays a vital role in various scientific fields, including astrophysics and cosmology. It helps scientists understand the behavior of objects in space, such as the orbits of planets around the Sun and the formation of galaxies. Accurate measurements of G are essential for precise calculations in these areas.