Center for Astrophysics | Harvard & Smithsonian scientists study planetary nebulas in several different ways: Identifying the atoms and molecules within planetary nebulas, mostly through the infrared light they emit and absorb. Infrared light can pierce through clouds of gas and dust, which are opaque to visible light.
How can a planetary nebula be identified?
What are some of the characteristics of planetary nebula?
Planetary nebulae are considerably denser than most H II regions, typically containing 1,000–10,000 atoms per cubic cm within their dense regions, and have a surface brightness 1,000 times larger.
What does planetary nebula look like?
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. … The term originates from the planet-like round shape of these nebulae observed by astronomers through early telescopes.
What makes a planetary nebula?
A planetary nebula is created when a star blows off its outer layers after it has run out of fuel to burn. These outer layers of gas expand into space, forming a nebula which is often the shape of a ring or bubble.
How are nebula observed?
Can I see it? Some nebulae are bright enough to be seen with the naked eye. The Orion Nebula is one of these, located between the stars in the constellation Orion's sword. Many others are visible through telescopes, depending on how many stars are around them to illuminate the dust clouds that form the nebulae.
Why do planetary nebulae look different?
We know that a planetary nebula is actually layers of gas ejected from a red giant star's outer atmosphere and lit up by the star's radiation. The different colours are from different chemical elements in the gas.
How do we determine the age of a planetary nebula?
Its age is equal to the distance the nebula has expanded divided by the rate at which it's expanding. One way we can figure out the rate at which its expanding is by observing the nebula over time and seeing how much it has expanded in that amount of time.
What color are planetary nebulae?
Planetary nebulae usually have relatively high oxygen emission, often making planetary nebulae appear blue-green in natural color. In wide field nightscapes, the tiny planetary nebulae often stand out in the Milky way as small green spots among the sea of yellow and red stars and brown-orange dust.
What is a planetary nebula stage?
The planetary nebula phase is a final stage in a low-mass star's life. During this phase, the star sheds its outer layers. This creates an expanding, glowing shell of very hot gas. … Low-mass stars turn into planetary nebulae towards the end of their red giant phase.