Newton's "law" of gravity is a mathematical description of the way bodies are observed to attract one another, based on many scientific experiments and observations. The gravitational equation says …

GRAVITATIONAL FORCE See Gravity GRAVITATIONAL PULL See Gravity GRAVITY The force of attraction between two objects which is influenced by the mass of the two objects and the distance …

An asteroid is a rocky body in space which may be only a few hundred feet wide or it may be several hundred miles wide. They are considered to be debris left over from the formation of the solar …

A star is a brilliantly glowing sphere of hot gas whose energy is produced by an internal nuclear fusion process. Stars are contained in galaxies. A galaxy contains not only stars, but clouds of gas and …

As the years progressed, Newton completed his work on universal , diffraction of light, centrifugal force, centripetal force, inverse-square law, bodies in motion and the variations in tides due to gravity. His …

1. Introduction: Review the definition of gravity Drop a ball and explain why it falls downward Explain that the strength of a gravitational pull is determined by the masses of the objects involved and the …

There is no current problem of greater importance to cosmology than that of dark matter. Dark matter is composed of particles that do not absorb, reflect, or emit light, so they cannot be detected by …

Redshift and Hubble's Law For very far objects (beyond about 1 billion light-years) none of the above methods work. Scientists must move from direct observation to using observations in conjunction …

The Planets and Dwarf Planets A planet is a large space body which reflects the light of a star around which it . The planets in our are classified as inner planets and outer planets. The inner planets, the …

Scientists believe that comets are made up of material left over from when the Sun and the planets were formed. They think that about 100,000 million comets orbit the Sun. Some comets orbit the Sun like …