If you rework what I did here with another distance in place of 1/2 of a light year:
https://www.physicsforums.com/showpost.php?p=1584381&postcount=18
You will find that the speed you get is the same. So, distance doesn't matter with my calculations either. That doesn't prove that the distance...
Tell me, how do you measure velocity?
EDIT: This is the main purpose of Lorentz transformations: http://en.wikipedia.org/wiki/Lorentz_transformation#Spacetime_interval
The idea is that the Lorentz transformations allow you to convert measurements from one observer to another when time is not...
Why? Because then the distance between two events in space-time would not be the same for all observers. The theory of special relativity postulates that c is constant (it did not prove it) to make the math work out nicely.
Of course you don't with the Lorrentz transformations. This is because each planet sees the other planet as being closer than it really is. Notice how in this example below, the perceived speed is lower than the actual speed:
Let me rephrase what I said:
Scenario 1:
Planet A is at location 0
Planet B is at location -1ly
Planet A sends a beam of light at c towards Planet B
Planet B moves towards Planet A at close to c
================
Planet B will receive the light in a little over 1/2 year
Scenario 2:
Planet A is...
Now, we could just as easily have a planet going very close to c towards us (only slightly less) instead of the light. Okay, so now if two planets 1 light year apart were traveling as close to c as possible towards each other, they could meet in only a little more than half of a year. Let's say...
The way I see it, holding c constant is just as arbitrary as making time universal.
I think it's silly to say that two objects, each 1/2 a light-year away from earth, one traveling at 2c/3 in one direction towards earth, and another traveling at 2c/3 in the other direction towards Earth would...