Ahad radius - where the Sun loses its supremacy

[Eridanus1]

This is relevant to solar astronomy, defining the edge of Sol's supremacy as the overwhelming provider of all light and heat to our Solar System -

On any interstellar journey going outward from Earth, one eventually reaches a point where the total amount of light received from our Sun is exactly matched by the total amount of flux coming from all cosmic sources external to our Solar System. The heliocentric distance of that boundary is dubbed the "Ahad radius", and exists at
the edge of "Ahad's sphere of solar illuminance", some 11,500 astronomical units (roughly a trillion [10^12] miles) from Earth.

On first definition of this heliocentric boundary, Abdul Ahad wrote:-

"Beyond the outer edges of this theoretical sphere, the feeble currents of light coming from its core (i.e. our own distant Sun) will cease to make any noticeable ripples in the calm waters of the surrounding cosmic ocean..." - July, 2004.

In the context of space exploration, no man-made spacecraft has yet escaped beyond the "Ahad sphere"; Voyager 1 is leading the charge and will reach the AR in just over 3,000 years from now. Voyager 2, Pioneers 10 and 11 will all follow after that.

From the paper:

http://www.astroscience.org/abdul-ahad/firstarktoalphacentauri/interstellar.htm

 

[AndyW]

Thank you for bringing up the concept of the "Ahad radius" and its relevance to solar astronomy. As a scientist studying the sun and its effects on our solar system, I find this concept to be quite intriguing.

The idea of a boundary where the total amount of light received from our sun is equal to the total amount of flux from external cosmic sources is certainly a significant one. It not only defines the reach of our sun's influence, but also highlights the vastness of the universe beyond our solar system.

I agree with Abdul Ahad's description of this boundary as the edge of "Ahad's sphere of solar illuminance". It is a fitting term to describe the point where our sun's light no longer has a dominant presence.

In terms of space exploration, reaching this boundary is a significant milestone. As you mentioned, no man-made spacecraft has yet escaped beyond the "Ahad sphere". It is a testament to the immense distance and challenges involved in interstellar travel.

I am also intrigued by the fact that Voyager 1 will reach the Ahad radius in just over 3,000 years. It is a reminder of the vastness of space and the long-term nature of space exploration.

Thank you for sharing this interesting concept and paper. I will definitely be looking into it further and considering its implications for my own research on solar astronomy.