The Cat's Eye Nebula is a brilliant nebula in the constellation Draco in the northern sky. The Cat's Eye Nebula has a complex and fascinating structure composed of several expanding spheres of gas. One of the most well-studied nebulae is the Cat's Eye Nebula. Despite all of the study, there remain numerous unanswered issues concerning the nebula's genesis and development.

Cat's Eye Nebula


The Discovery the Cat’s Eye Nebula

William Herschel discovered the Cat's Eye Nebula on February 15, 1786. Herschel was a German-born astronomer who immigrated to the United Kingdom at the age of 19. He constructed himself a telescope and began studying astronomy there. His early research was focused on planetary nebulae. He released a list of approximately 2,500 planetary nebulae in 1802 that included the Cat's Eye Nebula.

Read More — What is a nebula?

What is a Planetary Nebula?

Planetary nebulae, according to William Herschel, are the birthplace of planetary systems. He believed that the gas that surrounded the stars was condensing to form planets. Many other astronomers agreed with this notion, and the objects were dubbed planetary nebulae.

Herschel's idea, however, was incorrect. A planetary nebula does not produce planets. Planetary nebulae form when a star dies. Small and medium-sized stars will continue to shine for millions of years. Stars release stuff into space when they die. This stuff produces planetary nebulae and is the last stage in the life of a star. A star's demise can take tens of thousands of years. During this moment, the nebula expands.

How the Cat’s Eye Nebula has Evolved

A star's demise is a process that takes tens of thousands of years. The nebula's form alters as the process progresses. The Cat's Eye Nebula's intricate form was created by matter pulses released by the central star. The pulses happened about every 1500 years and generated the nebula's 11 or more concentric spheres of matter. The amount of stuff expelled in each pulse is greater than the total weight of all the planets in our solar system.

Scientists are baffled as to why the Cat's Eye Nebula spewed particles in pulses. There are several hypotheses. The first is that the pulses were caused by the star's magnetic activity. The magnetic activity is supposed to be akin to sunspots on our own sun. Another possibility is that the fading star was accompanied by another star. The gravity of this second star in orbit caused instabilities, which resulted in the pulses. The last explanation is that the dying star went through stellar pulsations, size expansions and contractions as it tried to regulate itself. The ejection of materials might be linked to certain stages of star pulsation.

The Cat's Eye Nebula was first seen by the Hubble Space Telescope in the early 1990s. These findings will aid astronomers' understanding of star death and nebula creation. The Hubble photos reveal that the Cat's Eye Nebula increased from 1994 to 2004. More nebulae must be researched before scientists can determine why nebulae expand.

Read More — Planetary Nebulas Info

What Gases are in the Cat’s Eye Nebula?

The Cat's Eye Nebula was the first nebula whose chemical composition was determined. Another English astronomer, William Huggins, began studying the Cat's Eye Nebula with a new type of device known as a spectrometer. Huggins was able to identify the chemical makeup of many celestial objects using the spectrometer. On August 29, 1864, he observed the first nebula spectrum, the Cat's Eye Nebula. His spectra demonstrated that the nebula was composed of gases.

William Huggins detected several strange lines in his spectrum when measuring the spectrum of the Cat's Eye Nebula. Spectral lines are associated with certain compounds and atoms, however this line did not match anything previously seen. Scientists determined that this line came from a new, previously undiscovered atom known as nebulium. It wasn't until the 1920s that physicists realized oxygen and nitrogen ions could generate this enigmatic spectral line. These spectral lines can only be seen under severe conditions, such as a nebula. Because they occur so seldom, these lines are known as forbidden lines.

Quick Facts about the Cat’s Eye Nebula

1.                 The Eye of the Cat NGC6543 is another name for the nebula.

2.                 It was first discovered in 1786.

3.                 The Cat's Eye Nebula was the first nebula to be spectroscopically investigated (in 1864).

4.                 It is made up of 11 or more expanding gas spheres. From our vantage point, these spheres appear to be rings.

5.                 The Cat's Eye Nebula was generated when an intermediate-sized star died.