I'm a scientist!

Draw a ball, where earth is center. That is the point how we can see at space.

Draw this ball six-directions; North-South-East-West-Down-Up; and point planets with distance km=si-units.

Say, how big is space, what we really have measured?

Why i talk cube-space? Because it is easy to understand, because our mathematics; Z-Y-Z-directions., where X-is north-south, Y-is East-West, and Z-is Down-Up.

So. Matter, planets, etc, has some point of this cube(ball) and between these points has distance. Time is only measuring unit, how long it take to travel between these points. If i travel must faster that maximum light speed is, then time is near zero. That is what i mean, that we cannot use time at measure space distance.

Speed of light is not constant. Why?