Questions tagged [nebula]
A collection of ionized gases and dust in interstellar space
14 questions with no upvoted or accepted answers
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Why does the core-mass luminosity relation work?
Why is luminosity of a star with degenerate core and He or H shell burning (RG, AGB or between Post-AGB and PN phase) given solely by the core mass? I understand that the relation is a stable result ...
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From what distance could the Sun's planetary nebula be seen entirely with free eye?
When collapsing to a white dwarf, a red giant Sun would emit a planetary nebula. How far from the Sun would that nebula stretch at most?
Also: At about what distance could you see the planetary nebula ...
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Can the "haze" of a mirror telescope be quantified?
When reading Why was StDr56 discovered only now? and its answers and comments, I realized that refractor telescopes, and in particular the Dragonfly Telephoto Array are a great tool to find nebula and ...
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Hydrogen Frost Line? Where, if anywhere, is it cold enough for Oort Cloud objects or rogue planets to have solid hydrogen on their surfaces?
I like the idea of Oort Cloud objects all being crusted with a thin layer of hydrogen snow, though what little information I've managed to find on the topic seems to imply that that is unlikely, ...
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Information on Planetary nebula formed from the death of our star the 'Sun'!
I want to know the expansion rate, composition, mass and density of hydrogen present of a Planetary nebula similar to that which will be formed after the death of our star the sun.
Knowing these ...
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What are the implications if the Sun was formed in a warm nebula?
Molecular oxygen O2 has been found on comet 67P/C-G in a ratio of 3.8% to water, which is much higher than expected. An explanation proposed is that the Solar System formed from a molecular cloud ...
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Can violet astronomical objects exist?
According to black-body radiation, violet stars are not possible.
Even if there are 1 million Kelvin, they are blue, not violet. But are violet galaxies, nebulae, clusters etc. possible?
Google found ...
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How to algorithmically distinguish between different types of nebulae?
I remember that there are five types of nebulae:
Planetary nebulae have not much to do with planets, but are emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red ...
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Are radio telescopes finding radio-dark Nebulas
Are there "dark nebula" spots in the sky for radio telescopes? By that I mean, are there portions in the sky where these telescopes do not receive any radio waves? If so, do they match ...
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What is Helix Nebula made up of?
The Helix is a planetary nebula, the glowing gaseous envelope expelled by a dying, sun-like star. Helix nebula consists of two gaseous disks, how they are formed or which material is present in it.
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Mass range of a sub-brown dwarf
Sub-brown dwarfs are celestial object that have planetary mass or are termed "Planetary mass object/planemos". They do not lie in the range 13-80 MJ that defines "normal" brown ...
user47732
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Who gave the Pelican Nebula its name?
IC 5070 is a nebula in Cygnus that is also sometimes called the Pelican Nebula. Who gave it this name?
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Does Nickel show up in spectra of Nova?
Does a nova, not a supernova, get hot enough that nickel is produced despite its formation by fusion being an endothermic reaction? If nickel is made, does it make it out of the star into the nebula?
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Star forming regions
Some star forming regions, like Bok globules (which contain stars that still haven't dispersed their molecular hydrogen and cosmic dust shell) appear dark compared to the rest of the H II in which ...
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