What planetary nebula means?

What planetary nebula means?

planetary nebula, any of a class of bright nebulae that are expanding shells of luminous gas expelled by dying stars. There are believed to be about 20,000 objects called planetary nebulae in the Milky Way Galaxy, each representing gas expelled relatively recently from a central star very late in its evolution.

What is planetary nebula quizlet?

A planetary nebula is the ejected shell of an evolved giant star. It is the shape of a spherical shell and is composed of relatively cool thing gas, which was once the outer part of the star. A planetary nebula is associated with the death of a low mass star.

Is our sun a planetary nebula?

Ultimately, most scientists believe that the Sun will become a planetary nebula. This is known as a planetary nebula—an expanding shell of hot gas that streams across the solar system after it is expelled from a star (the nebula itself is essentially the outer layers of the star).

Is the Crab nebula a planetary nebula?

One of the best examples of this is the Crab Nebula, in Taurus. The supernova event was recorded in the year 1054 and is labeled SN 1054. The compact object that was created after the explosion lies in the center of the Crab Nebula and its core is now a neutron star. Still other nebulae form as planetary nebulae.

Why is it called a planetary nebula?

NGC 1514: When William Herschel saw the bright star in the heart of this planetary nebula, he realized that he wasn’t looking at clusters but through gas and dust. As a result, he coined the name “planetary nebula,” because they shared the coloration of the recently discovered Uranus.

Why is a planetary nebula formed?

All planetary nebulae form at the end of the life of a star of intermediate mass, about 1-8 solar masses. Absorbed ultraviolet light then energizes the shell of nebulous gas around the central star, causing it to appear as a brightly coloured planetary nebula.

How does a planetary nebula form quizlet?

A planetary nebula is formed when a red giant ejects its outer atmosphere. The beautiful images show that a planetary nebula is a stage in the evolution of a low mass star. They last tens of thousands of years. A white dwarf is the carbon core of a red giant that has ejected its photosphere as a planetary nebula.

Why is a planetary nebula important?

Planetary nebulae are important objects in astronomy because they play a crucial role in the chemical evolution of the galaxy, returning material to the interstellar medium which has been enriched in heavy elements and other products of nucleosynthesis (such as carbon, nitrogen, oxygen and calcium).

What is planetary nebula made of?

A planetary nebula (PN, plural PNe), is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives.

How do planets form in a planetary nebula?

All planetary nebulae form at the end of the life of a star of intermediate mass, about 1-8 solar masses. Once all of the red giant’s atmosphere has been dissipated, energetic ultraviolet radiation from the exposed hot luminous core, called a planetary nebula nucleus (P.N.N.), ionizes the ejected material.

What is the composition of a planetary nebula?

Planetary nebulae are chemically enriched in elements produced by nuclear processing within the central star. Some are carbon-rich, with twice as much carbon as oxygen, while there is more oxygen than carbon in the Sun.

What is a planetary nebula?

Planetary Nebula A shell of gas from stars like our sun, at the end of their lifetime, there is no materials and they need to form a new star main sequence to red star

What was the original nature of the Saturn Nebula?

The nature of these objects remained unclear. In 1782, William Herschel, discoverer of Uranus, found the Saturn Nebula (NGC 7009) and described it as “A curious nebula, or what else to call it I do not know”. He later described these objects as seeming to be planets “of the starry kind”.

What is the brightest emission line in the Cat’s Eye Nebula?

Rather than a strong continuum with absorption lines superimposed, the Cat’s Eye Nebula and other similar objects showed a number of emission lines. Brightest of these was at a wavelength of 500.7 nanometres, which did not correspond with a line of any known element.