The ornamental design for a telescope, as shown and described.
FIG. 1 is an upper left perspective view of a telescope showing our new design, the undisclosed portions are not part of the claimed design and the shading indicates color contrast;
FIG. 2 is a left side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a rear view thereof; and,
FIG. 7 is a front elevation view of FIG. 1.
The broken lines in FIGS. 1, 4, and 6 form no part of the claimed design.