Hostile Witness. A witness at a trial who is so adverse to the party that called him or her that he or she can be cross-examined as though called to testify by the opposing party. The Federal Rules of Evidence provide that witnesses who are hostile, or adverse, can be interrogated through the use of leading questions. hostile witness
Polar wander. Polar wander is the motion of a pole in relation to a fixed reference frame. It can be used, for example, to measure the degree to which Earth's magnetic poles have been observed to move relative to the Earth's rotation axis.
The Arctic Circle is the farthest southern region that experiences polar day and polar night. A polar day is where it is 24 hours of continuous daylight, and a polar night is 24 continuous hours of darkness. North of the Arctic Circle more than one polar day and night occur per year.