In the 1840s, William Parsons, the Earl of Rosse, designed and built the world’s largest telescope. Known as the Leviathan of Parsonstown, it provided especially sharp views of the heavens. That made it well suited for studying faint, fuzzy nebulae, which showed little detail through lesser instruments.

Parsons turned his giant toward M97, an object near the Big Dipper. It had been cataloged by Charles Messier, a French comet hunter. Parsons’s drawing of the object resembled an owl — a bright disk with two round voids. The object became known as the Owl Nebula — a name it retains today.

The owl’s “eyes” appear to be large, empty bubbles inside two shells of gas.

The nebula was created by a dying star that’s blowing its outer layers into space. It expelled the first shell perhaps 10,000 years ago. The second followed a few thousand years later. Later still, the star expelled a third wave. It consisted of two separate bubbles that expanded from the star’s poles. They carved dark voids in the earlier shells. Those bubbles have stopped expanding. Eventually, they may collapse and fill with gas from the shells around them — depriving the owl of its distinctive eyes.

The Owl Nebula is about 2,000 light-years away. As night falls, it’s close to the lower right of Merak, the star at the bottom outer corner of the bowl of the Big Dipper, which is in the northeast. The Owl Nebula is an easy target for small telescopes.
 

Script by Damond Benningfield

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