B
bigbrain
Guest
You wrote:<br />“Go outside tonight as soon as the stars become visible. Mark their position in the sky. Note the time. Wait 4 hours then look at their position again. Their position has changed. Magic!”<br /><br />Not at all magic. The earth turns around itself, therefore it seems that the stars move. <br /><br />You wrote:<br />“Get in a vehicle. Look outside the window and not the position of the stars. Travel in the vehicle, noting all turns or deviations from a straight line, for 3 hours at 60 kph and note the position of the stars. I bet you'll see that their position has changed. Even more magic!”<br /><br />Not at all magic. If you look at the stars behind you for example, they are not the same you see in front of you.<br /><br />You wrote:<br />“Get in a vehicle. Look outside the window and not the position of the stars. Travel in the vehicle, noting all turns or deviations from a straight line, for 3 hours at 60 kph and note the position of the stars. I bet you'll see that their position has changed. Even more magic!”<br /><br />Those who live near equator turn around terrestrial axis at about 1,500 kph. Only if they went in the opposite direction at 1,500 kph, they would see the stars in the same position, because the earth turns around itself.<br /><br />You wrote:<br />“Now that you know what happens when you turn and travel in relationship to the stars position and the time/velocity traveled, you can navigate using the stars. <br />If you can orient a craft in space so that the stars line up according to a predefined pattern, then you can know that craft's position in space. Using time honored calculations from Newton et al, you can then plot a course if you know the velocity you need and the amount of time needed at that velocity to get to another point in space. You can even make course corrections along the way by resighting your craft's position. Simple. We're talking about very short distances with very small allowances for error that are acceptable for interplan