Questions tagged [star-formation]
Questions related to the physical processes involved in or to the observations of the process of forming a star.
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What is the origin of the dust near the sun?
note: Solar Probe+ is now officially Parker Solar Probe
In How can the Parker Solar Probe survive passing within 4 million miles of the sun's surface? I asked about the Solar Probe Plus mission. ...
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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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Why are the Pillars of Creation pillar-shaped?
The Pillars of Creation have a strong directional sense. They are referred to as "pillars" and another question asks how "tall" they are. Naively, it looks as if there is a source ...
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Which came first: Galaxies <=> Stars <=> Planets?
If a galaxy is defined as a collection of planetary systems (and all matter in between), and a planetary system is defined as a collection of planets circling a star (and all matter in between), and a ...
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Estimating a star's radius, temperature, and luminosity based on its mass
(See updated figure and description below.)
I've been trying to generate ballpark estimates for the radius, temperature and luminosity of stars in the main sequence based solely on their masses (...
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What is the largest hydrogen-burning star?
I am wondering what is the largest known core hydrogen-burning star? A look at the list of largest known stars on Wikipedia seems to indicate VV Cephei B (at the bottom of the list), but I would like ...
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A few questions regarding the transit of planets
Here we will be concerning ourselves with the transit of a planet with it's parent sun.
I have a few questions that I am not sure about:
1) Do all planets transit their parent sun? It would seem to ...
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Remains of the progenitor of the Sun
It has been argued that it is not possible to trace back the remains of the progenitor star of the Sun (sometimes called Coatlicue), which, being estimated in the mass range of 30 $M_{\odot}$, should ...
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What is the minimum size of a ball of gas to become a star?
I know there are two criteria to meet in order for nuclear fusion to occurs.
High temperature (many times temperature at Sun's core)
High pressure (protons are very close to each other)
[Goal]
...
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Distance of extra-galactic Classical Cepheids
There have been many questions and answers about finding the distance of a star from the earth. But as I did some research on the net, I found that we have specific approaches for finding the ...
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Does the Sun rotate?
The planets rotate as an after effect of their creation, the dust clouds that compressed span as they did so and the inertia has kept it rotating ever since.
It's fairly easy to prove that planetary ...
user96
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How are binary star systems created?
I don't know how common it is for a system to have two stars (or perhaps even more) but how do they arise? Is that due to the stellar accretion disc, or the composition of the stellar nebula?
Or are ...
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Why is the composition of the sun so distinct from that of earth?
Given that the sun is – in astronomical distances – quite close to the earth, why are the two composed of such distinctly different substances?
Sun Composition
Hydrogen 74.9%
Helium 23.8%
Oxygen ~1%
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Is there a (proposed) name for Coatlicue's progenitor?
Our sun's theorized progenitor star carries the (proposed) name Coatlicue. Since our sun is thought to be a third generation* star there should be two generations preceding it - and therefore one ...
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Mechanism for Brown Dwarf Fusion
I've read (at here, among other places) that during the Degenerate Era, star formation will end and the last stars will go out. But it was noted that there is still the possibility of star birth, ...
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Are metallicities of molecular clouds lower in the outskirts of the galaxy?
(this question was originally posted in an answer by user PSR-1937-21 to another post. I find it an interesting one, but since they don't seem to be active anymore, I'm posting it to see if somebody ...
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Can a donut-shape planet or star be formed?
How stable is a donut-shaped star or planet configuration and under what conditions such object may form?
Is there any evidence suggesting that such objects might exist?
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Formation of the First Stars
I've got a few questions about the first stars to form in the universe. First off how might metalicity have impacted the formation of the first stars and also what effect would the absence of metals ...
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Where do new stars get their hydrogen from? [duplicate]
When stars run out of hydrogen, they explode (though they also use heavier elements for some time) and form nebulae. In the nebulae, new stars are born which use hydrogen as their fuel.
So, my ...
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Stellar nurseries in the "Shedding New Light on the Whirlpool Galaxy" video
Captions in the Hubble Space Telescope YouTube channel video Shedding New Light on the Whirlpool Galaxy say:
(visible) Along the dark dust lanes, bright pink nebulae are the birthplace of new stars.
(...
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What exactly are infrared dark clouds and what is the significance of the orientation of their magnetic fields?
In the video Why NASA's SOFIA Telescope On A Plane is "Perfectly Balanced" after about 10:04 SOFIA associate director James Jackson says:
We have a ...
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Could the earth become a star if more mass was added?
I've heard that the only difference between a star and a planet is mass, meaning that if planets accredited enough mass they would too become stars.
Does this mean that the star started off as a ...
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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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Term for the moment when hydrogen fusion begins in a star
I have read of this process many times, but I don't think I know the term specifically for the moment when hydrogen fusion begins. What is this moment called?
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Could our Sun be the product of an ancient stellar collision?
The canonical model for the formation of the Solar System involves the gravitational collapse of a nebula into (perhaps) several stars across several light years. Is it possible that two or more of ...
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Star formation analogy
If I have understood correctly, stars form in big clouds of gas and dust that are pulled together by their gravity. And the stars are often ignited when something disturbs the cloud, such as a passing ...
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Is the magnetic field strength of a star predictable from mass, composition, age and angular momentum alone?
This answer to Which stellar properties can we describe as “first principles” in which we can derive the rest? contains an intriguing bit:
That states that composition and mass are the two key ...
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How could a supernova seed solar nebula?
If the heavier elements such as Uranium came from a supernova, then this supernova had to sit somewhere right in the middle of the original solar nebula, because although the ejected matter traveled ...
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Is it possible that some "stars" or "black holes" have "wormholes" in their center? [closed]
Seems like if the mass of a "star" or "black hole" changed without absorbing or expelling anything, then that would be an indicator that there is a "wormhole" inside.
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