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The Big Bang theory predicts that (depending what assumptions you choose) the initial elements were formed from 10 seconds to 20 minutes after the Big Bang. The initial elements were mostly hydrogen some deuterium some helium-3 and helium-4 a little lithium-7 a couple of unstable isotopes that decayed to lithium-7 or helium-3. As the linked Wikipedia ...


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Since you phrase your question "What type does theory predict?", I guess the answer must be the so-called Population III stars, which are thought to be the first generation of stars, born from zero-metallicity gas. With no metals, it is difficult for the gas to cool. The mass of a star is given by the Jeans mass of the collapsing cloud, which is proportional ...


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There is no particular type. Yes Wolf Rayets were once more massive and have suffered extensive mass loss. Other examples of evolved massive stars are very luminous red supergiants and luminous blue variables (LBVs). The evolutionary tracks through these processes are somewhat poorly understood, as are the exact magnitudes and durations of the various mass ...


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Stanley, there really isn't a very clear definition and this is still a keenly argued point. Definitions include: Browns dwarfs burn deuterium. In models this happens if they are more massive than about 13 times Jupiter. The weakness of this that we think isolated brown dwarfs could condense from a gas cloud that are less massive than this; and young brown ...


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There are apps which will help guide you to more significant stars (Google skymap comes to mind if you're looking for a simple mobile system - Stellarium may also be a good option), but it's highly unlikely that any app will include the location and names of so-called 'personal' stars, as the bodies who sell such things don't have any the authority to do so ...


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The Chandrasekhar limit in general does not pertain to the mass of the star as a whole. It addresses the mass of the degenerate core. It's only in white dwarfs where the Chandrasekhar limit applies to the mass of white dwarf as a whole, but that's because white dwarfs are almost entirely degenerate matter. Consider a 1.6 solar mass that is not a member of a ...


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The Chandrasekhar limit applies only for white dwarfs. Stars on the main sequence (or even off the main sequence) can easily surpass it, but if a white dwarf's mass is greater than the Chandrasekhar limit ($1.39 M_{\odot}$), it will undergo some sort of collapse. First, though, in response to Or has it already undergone supernova explosion? White ...


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Does the Sun turn around a big star? No. Such a star, if it existed, would easily be the brightest star in the sky. You would have been taught about it early on in school if it existed. But it doesn't. For a while it was conjectured that the Sun had a small companion star to explain a perceived periodicity in mass extinction events. This too has been ...


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The Sun is not within the gravitational sphere of influence of any other star. The centre of mass of the solar system (which is very close to the Sun) instead orbits in the general Galactic gravitational potential. Because this has a roughly cylindrical symmetry (the Galaxy is basically a disk with a bulge in the middle), this means that it executes a ...


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The Sun has lots of features "like the red spot", but they are dissimilar too. Similarities: The Sun's photosphere - the bit we can see - is entirely gaseous; the photosphere rotates differentially with solar latitude; the gas is turbulent. There are features that can be seen quite easily - these are the dark magnetic sunspots, typically of size a few ...


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Ahh got it. The coordinates are given as latitude, longitude. Fortunately, the longitude hardly matters (depending what precision you need), but the latitude does. A star at the zenith will have a declination equal to the latitude on Earth. As far as Right Ascension goes, well around the March equinox then stars with 12 hours in Right Ascension will reach ...



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