Cryogenic cooling positioning apparatus, methods and applications

A method, comprising:

• providing a cryogenic sample positioning structure, comprising:
• at least one sample holder cassette comprising at least one opening that is vertically coupled to an upper surface of a carousel gear through a first axle shaft, wherein the at least one sample holder cassette has a first degree of rotation about the first axle shaft;
• a first planet drive gear underlying and vertically coupled to the carousel gear through a second axle shaft that extends from the carousel gear through the first planet drive gear, wherein the carousel gear and the at least one sample holder cassette each have a second degree of rotation about the second axle shaft that is independent of the first degree of rotation;
• and
• at least one planet gear that is laterally connected to a second planet drive gear, and is interposed between each of the carousel gear and the first planet drive gear, wherein each of the at least one planet gear and the second planet drive gear selectively define the first degree of rotation, without affecting the second degree of rotation of the carousel gear;
• and
• disposing the cryogenic sample positioning structure within a cryogenic chamber having an opening, wherein the at least one opening of the at least one sample holder cassette is directly aligned with the opening of the cryogenic chamber so as to accurately position a sample within the at least one opening.