APOD MyCn18 An Hourglass Planetary Nebula

The sands of time are running out for the central star of this hourglass-shaped planetary nebula.

With its nuclear fuel exhausted, this brief, spectacular, closing phase of a Sun-like star's life occurs as its outer layers are ejected - its core becoming a cooling, fading white dwarf. In 1995, astronomers used the Hubble Space Telescope (HST) to make a series of images of planetary nebulae, including the one above. Here, delicate rings of colorfu

Source:
http://apod.nasa.gov/apod/ap110807.html