The Eye of an Hourglass Nebula . ... Credit Copyright: R. Sahai and J. Trauger ( JPL ), WFPC2 Science Team , NASA Explanation: What's happening in the eye-like center of this planetary nebula? The geometry revealed in this Hubble Space Telescope view of the central part of an " etched hourglass nebula " known as MyCn 18 presents a puzzle. First, the axis of this central region does not line up well with the outer hourglass structure. ... NASA Web Site Statements, Warnings, and Disclaimers . ...