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The Carina Nebula is an example of a diffuse nebula. Most nebulae can be described as diffuse nebulae, which means that they are extended and contain no well-defined boundaries. [24] Diffuse nebulae can be divided into emission nebulae, reflection nebulae and dark nebulae.
IC 349, small reflection nebula in the Pleiades; IC 2177; IC 2631, reflection nebula in Chamaeleon; IC 4604; IC 4605; IC 5146; Sharpless 2-1; Sharpless 2-112 ...
The nebula's color depends on its chemical composition and degree of ionization. Due to the prevalence of hydrogen in interstellar gas, and its relatively low energy of ionization, many emission nebulae appear red due to strong emissions of the Balmer series. If more energy is available, other elements will be ionized, and green and blue ...
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[1] [2] They are believed to be a common feature of the evolution of planetary nebulae, but can only be resolved in the nearest examples. [2] They are generally larger than the size of the Solar System (i.e. the orbit of Pluto ), with masses of around 0.00001 times the mass of the Sun , which is comparable to the mass of the Earth .
NGC 6326, a planetary nebula with glowing wisps of outpouring gas that are lit up by a binary [3] central star. A planetary nebula is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. [4] The term "planetary nebula" is a misnomer because they are unrelated to ...
The Helix Nebula (also known as NGC 7293 or Caldwell 63) is a planetary nebula (PN) located in the constellation Aquarius. Discovered by Karl Ludwig Harding , most likely before 1824, this object is one of the closest of all the bright planetary nebulae to Earth. [ 3 ]
An alternative definition is that the penumbra is the region where some or all of the light source is obscured (i.e., the umbra is a subset of the penumbra). For example, NASA 's Navigation and Ancillary Information Facility defines that a body in the umbra is also within the penumbra.