Copy and paste work, but the other instructions in the helpfile (with numlock on, type alt+0080) didn't seem to have any effect (other than a beep when the 0 is pressed).
Any two orbits that share a point in space must share the point that is on the opposite side of the earth due to the fact that they are both doing giant circles about the center of the earth. Think of two infinitely thin hula hoop, one inside the other.
What if one has a circular orbit and the other an eccentric orbit, and these orbits simply happen to intersect at this point which they "share"? There will be no point on the opposite side of the planet where the orbits again intersect.
If you throw an object from an orbiting station, you are imparting a velocity on it which is different from the station from which it was thrown. Would its orbit not then become eccentric (assuming that the station had a circular orbit)?
What if one has a circular orbit and the other an eccentric orbit, and these orbits simply happen to intersect at this point which they "share"? There will be no point on the opposite side of the planet where the orbits again intersect.
If you throw an object from an orbiting station, you are imparting a velocity on it which is different from the station from which it was thrown. Would its orbit not then become eccentric (assuming that the station had a circular orbit)?
If you have an object in a circular orbit and you give it a push away from the earth it's orbital period wont change, all that will happen is it will oscillate about the circular path. The period of oscillation will be one revolution and so the new orbit will intersect the circular orbit twice per revolution. This is an eccentric orbit.
If you were in space and threw anything, boomerang, spanner, feather etc, at 90° to your direction of travel then you will meet it again on the other side of the earth. As both you and the object are doing great circles your paths will cross twice per orbit.