Note: It is possible that 'Hubble's constant' is not a constant, but rather that it should be 'Hubble's variable' for the red-shifting of light might be dependant upon the strength of the gravitational field (therefore the constant calculated for an object rising in the sun's gravitational field may not apply everywhere in the universe. I am not certain yet whether or not this is the correct conclusion but I mention it as a possibility.


The constant deceleration of the Pioneer craft as they rise up in the gravitational field of the sun is quite close to the value of the speed of light multiplied by Hubble’s constant. There are many different methods used to calculate Hubble’s constant all of which produce different results. It has occurred to me that the correct value of Hubble’s constant must be the value that, when multiplied by the speed of light, results in the exact rate of constant deceleration experienced by the Pioneer craft.

As the Pioneer craft decelerate, the clock is running faster, and the speed of light is increasing. Now the close correlation that exists between the Pioneer deceleration rate and Hubble’s constant suggests red-shifting, and this is what you would expect if light were to red shift as its relative speed increased.

We should think of the entire universe as being an energy field. As the density of the field decreases (the inverse square law dictates this rate of decrease) the allowable energy levels decrease, and the frequency and wavelength of the light decrease (red-shifts). The light thus becomes less energetic, but the law of the conservation of energy requires that this energy be conserved, and apparently it is conserved in the form of ‘increased momentum’, so that light red-shifts in order that its speed might increase. In this way the speed of light remains ‘constant’, no matter how the density of the energy field changes. Where the field is less dense, the clock runs faster, and the relative speed of light increases (the speed of light is always 300,000 kilometers per second to an observer sharing the space with the light, but there is a relative increase in speed that can only be noticed by an outside observer…for this reason I refer to the speed of light as being a variable constant).

Determining the exact value of Hubble’s constant is very important when it comes to answering such questions as ‘how far away is such and such an object in space’ or ‘what is the age of the universe’, and all the different values give different answers to these questions. Knowing the precise value of this constant would be very useful, and it would seem that the Pioneer data provides the final and definitive answer to that question.