Another Eye Of Sauron Nebula

This planetary nebula, dryly called ESO 456-67, might evoke a much more colorful naming by some, owing to it resembling a fiery eye in the sky--and alluding to something from The Lord of the Rings. And there are actually several other candidates of nebula resembling an eye in space, most famously the Cat Eye nebula--thanks to the Hubble Space Telescope and LOTR movies, this won't be the last such article either.

This blue and purple colored nebula lies in the constellation of Sagittarius (The Archer), in the southern sky. Despite the prefix "planetary", these interstellar objects have nothing at all to do with planets. The misnomer came about over a century ago, when the first astronomers to observe them only had small, poor-quality telescopes. Through these, the nebulae looked small, compact and planet-like.

When a star approaches the end of its life, it flings material out into space. Planetary nebulae are the spiry, glowing shells of dust and gas pushed outwards from such a star. At their centres lie the remnants of the original stars themselves - small, dense white dwarf stars which can glow on for billions of years.

In this image of ESO 456-67 taken by Hubble, it is possible to see the various layers of material expelled by the central star. Each appears in a different hue - red, orange, yellow and green-tinted bands of gas, with clear patches of space at the heart of the nebula.

It is not fully understood how planetary nebulae form such a wide variety of shapes and structures. Some appear to be spherical, some elliptical, others shoot material in waves from their polar regions, some look like hourglasses or figures of eight, and others resemble large, messy stellar explosions - to describe but a few.