Nebulae can be difficult to detect due to their vast distances from Earth and their often faint luminosity. Many nebulae are composed of diffuse gas and dust, which can obscure them from view, especially if they are located within the plane of the Milky Way. Additionally, some nebulae emit only in specific wavelengths, such as infrared or radio, requiring specialized instruments to observe them effectively. This combination of factors makes identifying and studying nebulae a challenging task for astronomers.
The lifespan of a nebula can vary significantly depending on its type and the processes occurring within it. For instance, a star-forming nebula can last for millions of years as it gradually converts gas and dust into new stars. In contrast, a planetary nebula, which represents the late stages of a star's life, may exist for only a few tens of thousands of years before dissipating. Ultimately, the "death" of a nebula is a gradual process influenced by internal dynamics and external factors, making it difficult to pinpoint an exact timeframe.
Emission nebula glow and reflection nebula reflect the light form other stars
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An absorption nebula is a dark nebula, which absorbs all incident radiation without reemission.
It's difficult to be precise because of the great distance from us (~6,500 light years). It either lies on the rim of the Orion arm or the rim of the Perseus rim. [See related link]
A new star will usually have hydrogen alpha light. This light is red but is difficult for the human eye to detect. If you look up M42, the Great Orion Nebula, most long exposure photographs will show this red light.
Because nebula, like galaxies, do not have a defining edge, it is difficult to determine the exact size but an estimate is the closest you'll get.However, in this case, the difference is large enough.The Tarantula Nebula is about 15 times larger than the Carina Nebula.Tarantula ~ 1,000 light years acrossCarina ~ 65 light years across.
Radon is a gas, odorless and colorless. But with the appropriate equipment the detection of radon is possible and not so difficult.
nebula
They probably don't cross them enough.
The Stingray Nebula (Hen 3-1357) is a planetary nebula. (The youngest known).
Most viruses are too small to be seen with a light microscope because they are smaller than the wavelength of visible light. This makes it difficult to detect them using this method.
The lifespan of a nebula can vary significantly depending on its type and the processes occurring within it. For instance, a star-forming nebula can last for millions of years as it gradually converts gas and dust into new stars. In contrast, a planetary nebula, which represents the late stages of a star's life, may exist for only a few tens of thousands of years before dissipating. Ultimately, the "death" of a nebula is a gradual process influenced by internal dynamics and external factors, making it difficult to pinpoint an exact timeframe.
"The Crab" is a nebula.
a type of nebula
A cloud in outer space consisting of gas or dust and planetry nebula is one of the types also called ring nebula or A planetary nebula is an emission nebula consisting of a glowing shell of gas
The Helix Nebula is a planetary nebula located in the constellation Aquarius, while the Ring Nebula is a planetary nebula located in the constellation Lyra. The Helix Nebula appears more like a disk or helix shape, while the Ring Nebula appears as a ring or donut shape due to its orientation.