Questions tagged [nebula]
A collection of ionized gases and dust in interstellar space
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Will new stars stop forming at some point of time?
New stars keep forming in the universe thanks to all the nebulae. Now, we need Hydrogen to form stars and there would a time when all the hydrogen will get exhausted, and no more star formation will ...
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How many stars and galaxies can be seen by the naked eye?
How many of the luminous dots that we see naked are galaxies and not stars from our galaxy?
I imagine that the majority of the luminous points that we see naked eye during the night, are actually ...
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Why is the Boomerang Nebula colder than the CMB?
An earlier answer on temperature mentioned that the temp of the Cosmic Microwave Background (CMB) is $2.4\,{\rm K}$ and the temp of the Boomerang nebula as ${\rm 1\,K}$. How did the nebula cool faster ...
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Why is said that H-alpha emission lines are stronger than the other of the Balmer series?
H-alpha lines are usually the ones you see when observing most nebulae.
If you search why is that, why are H-alpha lines more visible than H-beta, H-gamma or H-delta, the usual answer is that H-alpha ...
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Whose name is Fleming 1 nebula bearing?
Fleming 1 is an unusual planetary nebula situated in the Centaurus constellation.
Yet it is not clear after who it was named
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How do I see more than just points in the sky?
I just bought a new telescope with these specifications:
Aperture: 203 mm
Focal Length: 1200 mm
F/ratio: f/5.9
I usually use a 28 mm eyepiece, giving me about 42.5x magnification, but I also have a ...
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Nebula and its colors
A Nebula has bright awesome colors that include red, blue, green, orange, white, etc?
They're result of excitation of electrons.
Is there a clear explanation as to which color is attributed to an ...
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What causes the sharp if irregular boundary line in the "Cosmic Cliffs" JWST Carina image?
In this recently released JWST image:
we can see a relatively sharp, if irregular, boundary line between a region appearing mostly bluish and a region appearing mostly reddish or orange (understood ...
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Why can space telescopes see through a planetary nebula?
I recently read the book "An Introduction to Planetary Nebulae" by Jason J. Nishiyama. Although I'm not an astronomy student, I could at least understand the written texts and less the ...
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Is it possible that the Sun and all the nearby stars formed from the same nebula?
I was looking at a map of our local stellar neighborhood, and it occured to me, the stars are really close, if one compares them to the size of some nebulae. So can it be, that the Sun, Alpha Centauri ...
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What are the large round dark "holes" in this NASA Hubble image of the Crab Nebula?
I came across this image of the Crab Nebula taken from NASA Hubble telescope. What are the large round "holes" and how are they formed?
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Are Brown and Sub-Brown Dwarfs secretly more common than stars?
I recently heard that Red Dwarfs are the most common type of star, and low-mass Red Dwarfs are the most common type of Red Dwarf. This seems to imply a generic trend that the lower the mass, the more ...
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What is the bright orange star?
After reading this NASA article on Tarantula's Nebula of this image:
What is the really bright orange star in the center or upper-left of the young blue stars? The second link further provides ...
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Will the nebula of Betelgeuse be visible to the naked eye? How bright, how large, how soon, for how long?
When Betelgeuse goes core collapse supernova it will leave a supernova remnant. Will it become visible to the naked eye? If so, in what time frame will it be visible. Will it be star like from the ...
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Are nebulae only visible from a distance?
There's plenty of data about the density of nebulae, and obviously they're pretty thin. This is space, after all, and these things are really, really big.
But I'm wondering about the practical ...
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Why are O III lines so prominent in the spectra of emission nebulae when the amount of oxygen relative to hydrogen is a million times smaller?
Looking at spectra of emission nebulae like the Lagoon Nebula, the $[\text{O III}]$ lines are prominent in intensity. However, the abundance of oxygen is minuscule compared to hydrogen. How then are ...
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Why was StDr56 discovered only now?
StDr56 is a newly discovered planetary nebula (maybe). link1 link2
It was found by amateur astronomers Marcel Drechsler and Xavier Strottner.
According to the above articles, it's pretty big:
With an ...
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How can an accretion disk form around the central star of a planetary nebula?
I was reading the 2012 paper A tidally destructed massive planet as the progenitor of the two light planets around the sdB star KIC 05807616 about the possible origin of two exoplanets that orbit a ...
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What are the dark spots in this Hubble image of the Crab Nebula?
I recently ran into this NASA Hubble image of the Crab Nebula in this article talking about its core. What I am interested to know though is: what are these round dark spots appearing in the image (...
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Do heavier elements breakdown during supernova?
Heavier elements like gold, uranium etc. are formed at the end of a star's life. As the star explodes into a supernova, it gives rise to nebula which is the birthplace of new stars. But as the star ...
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How tall are the pillars of creation? (angular and physical) How bright are they? [duplicate]
NASA's October 19, 2022 NASA’s Webb Takes Star-Filled Portrait of Pillars of Creation shows a sparkly and beautiful infrared image of the Astronomical elephant trunks known as the Pillars of Creation.
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