The following text derives a gravitational constant when gravity is a pushing force, which gives the same results as Newton's Gravitational Constant.

If the gravitational force we feel on earth is caused by gravity coming from space and not from earth, the relationship of gravitational force and mass must mean gravity passes through the earth. If gravity comes from outer space and after passing through the earth, has a diminished force, the force of gravity having passed through will be less than that coming from outer space. For this to be true the difference would have to be the force we feel and measure but would be caused by a pushing force instead of the accepted one of pulling. An analogy of this would be a light shining from all directions on a slightly opaque glass sphere, the intensity of light at the surface of the sphere would be less facing the sphere than facing away from it.

The calculations that follow show that this reasoning gives the same results as Newtonian gravitational theory but additionally shows that the singularity at the big bang could also be a singularity at galactic scale. It also shows that the orbital velocity of stars in a spiral galaxy will be fairly constant regardless of distance from the galaxy centre thus obviating the need for dark matter. It also suggests that the principle forces within an atom's structure could be gravitational forces.

Observation of stars in a spiral galaxy shows a star's velocity to be fairly constant as the distance from the centre of the galaxy increases. Newtonian gravitational calculations require the velocity to decrease and invisible (and undetected) dark matter is needed to keep the velocity constant. If gravity is a pushing force dark matter is not needed for a star to have a constant velocity in a spiral galaxy.

The force on a body at the extremity of a spiral galaxy is influenced by the diameter, density and length of all the bodies in a radial line passing through the galaxy. The body can be centered on the extreme location and the line (diameter) is the length to the other extremity and passing through the centre of the galaxy. This will give a force towards the galaxy centre which is more than that calculated by Newtonian calculations.

The orbital velocity of stars is likely to remain fairly constant as the distance from the galaxy centre increases since

centripetal force | = | Mass x velocity^{2}/radius |

and as the radius increases the equation for pushing gravity uses the mass of the line or column of stars which also increases.

From the derived equation for the force of gravity in a spiral galaxy the calculated velocity remains constant as the radius increases. This obviates the need for dark matter.

If inertial forces are created when gravity is pushing it can be argued that gravity is not inertial, and the gravity particle velocity, depending on its equivalent mass, will be about

6.59 x 10^{14} x c (where c = speed of light) |

If a body is held together by a pushing gravity any change in speed or direction will create an inertial force until gravity and body forces are re-balanced.

If gravity comes from outer space it may be wholly or partly produced in stars. When the converged properties of the earth and sun and the orbit of the earth around the sun are determined there is a slight imbalance between gravitational and centripetal forces. If this slight imbalance is corrected by gravity produced by the sun, the amount of gravity per kilogram of the sun can be determined. A further consequence of this reasoning is that if the sun had its mass increased with constant density a point would be reached when the gravity coming out of the sun equaled the gravity coming from outer space.

At this point when the sun's net surface gravity force would be zero, the sun would have a mass of 7.03241 x 10^{39}kg. If production of gravity is also dependent on the temperature of the star, cooler bodies collecting under space gravitational force could have a greater mass than could be sustained after warming up by compression and nuclear reactions. This suggests big bang singularities could occur on the galactic scale and also the universal scale.

The Newtonian universal gravitational constant is based on observations and assumes gravity is a pulling force, but a constant can be derived if gravity is assumed to be a pushing force.

Richard Feynman found that over the past 200 years there had been several attempts to show that gravity pushed, but the retardation forces on the earth in its orbit around the sun associated with these proposals would have a far greater effect than that which is observed. In this proposal the earth's velocity though space is negligible compared to the postulated speed of gravity and results in a negligible reduction in earth's velocity. With gravity pushing there is still sufficient time for the earth to be absorbed by the sun.

Derived Value for a Universal Gravitation Constant for Pushing Gravity