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The Sun is left with a net negative charge as it continually ejects large composite streamers of primarily protons in the solar wind. This builds up and sustains a “Solar Capacitor” with the positive anode far beyond the orbit of Pluto, where there is a large ionized cloud of dust and gasses. This capacitor is discharged by the asteroids and larger comet ...


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I'm not sure if this is a misunderstanding or just a matter of scientific terminology, but the "star cycle" is not something you can "drastically change". The life cycle of a star (as we currently understand it) is a fairly predictable set of stages of evolution from the formation of a star from a cloud of gas, along the main sequence (the stable stage out ...


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The bulge population is old, older than 10 billion years. Its stars have a broad range of metallicities, but are more metal rich than population II, have an average close to solar metallicity and a significant fraction more metal rich than the Sun. The basic idea is that the bulge population is one that formed very quickly, with a high rate of gas infall and ...


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It has to do with the formation of the Milky Way. At the beginning, the Milky Way was much more spherical than it is now - perhaps closer to what an elliptical galaxy is like than a spiral galaxy. Population III stars would have formed first, then quickly died out. Next came Population II stars. They formed when the galaxy was still somewhat spherical, and ...


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I will say, two years late I suppose, (lol) that on a true scientific basis, we cannot factually say yes or no to the question. You have been given excellent theories on the matter, but in order to answer that question, one would need to document and follow the life of one single atom, how it becomes whatever it becomes, and track it all the way to it's ...


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While I agree that it boils down to semantics, I actually disagree on the scientific use of the term in the comments. In astronomy, we know there's a difference between gas and plasma, but we almost always use the term "gas" when talking about what's in stars. E.g. "the fraction of gas locked up in stars" (as opposed to in the interstellar medium). We also ...


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I've been pondering the dimming of this star for a couple months now and have come up with a plausible explanation. The dimming is probably caused by a very dim companion dwarf star in a highly elliptical orbit where its closest approach to KIC8462852 (Tabby's Star) is on, or near, the same path as our line of sight. The gravitational pull from the dwarf ...


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There are some theories to explain that. The following explanations, I took from wikipeda's article. The star has a small companion red dwarf which just crossed its Oort cloud equivalent (at 885 UA). A passing star this close would surely cause havoc and serious disturbances to comets' orbits. This could result in a swarm of comets being thrown into the ...


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This image should give you a good idea of the distances of stars relative to the Sun over the next 80,000 years (and the past 20,000 years). Image courtesy of Wikipedia user Lambiam under the Creative Commons Attribution-Share Alike 3.0 Unported license. I've created a modified version below. The nearest star's track in time is in red, and the four blue ...


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No. The light curves don't look at all like anything transiting. The ingress and egress profiles and the timing are way beyond that kind of explanation. Not planets, not comets, not clouds, not alien super structures. No infrared light from dust or gas has been detected, as they should've been if the starlight had heated small particles. And since this is ...


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All star names are unofficial. A few stars have ancient names (such as Sirius) all other stars are referred to by their position in a catalogue or star atlas. As well as I can tell, Al Sadira means "the ostrich", or perhaps in context "The (riverbank) ostrich" indicating a type of tree that grows by rivers (baby name sites offer "lotus tree"). There may be ...


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Alternatively, if you were to get the Right Ascension and Declination coordinates from the company that sold you the star you could use a database like SIMBAD to find the actual designation of the star you purchased. You could then probably use the SIMBAD designation to find the star using Stellarium. Here's a link to the SIMBAD database: ...


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A consensus number is that there roughly $10^{11}$ stars in our Galaxy (though this number is certainly uncertain by a factor of at least two, because it is based on extrapolating what we know about stellar populations in our vicinity). Most of these stars are of lower mass and are much less luminous than the Sun. The number of planets is even more ...


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OK, it seems to me that what you have is a fits image (from where?) that has some world coordinate system information attached. When you load the 2MASS catalogue, SAOimage is able to use the RA and Dec in the catalogue to calculate the x,y positions of the catalog sources in your image (and marks them as green circles). Is what you are asking - how do I get ...


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EDIT: It turns out a major problem with galaxy-center-based coordinates is that we don't actually know how far from us the center of the galaxy actually is. According to https://en.wikipedia.org/wiki/Galactic_Center estimates vary between 24,800 and 28,400 light years. You could arbitrarily choose a value, but the results would be off by at least 2,000 light ...


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The size of the accretion disc in a black-hole binary system is calculated to be less than 1000000km. This is less than to the size of large stars (eg Spica at about 10000000km diameter). In other words, the accretion disc for a large star would be smaller than the star itself.


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Many, if not all, stars will, in their birth phase, have an accretion disk, or circumstellar disk, around them, formed of the material from which the star forms. This disk dissipates in a few million years, both due to the material accreting onto the star, due to material being blown away by radiation pressure, possibly assisted by dust grains, and due to ...


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It is true that a surprisingly large number of stars are smaller (and thus less massive) than the Sun. However, the stars that are bigger than the Sun are often much bigger. Look at this chart: Image courtesy of Wikipedia user Jcpag2012 under the Creative Commons Attribution-Share Alike 3.0 Unported license. Notice how small the Sun is compared to some ...


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Recently NASA has revealed that they have recorded the sound of Sun. They say that it produces a sound like "Om". I can't understand how they can hear it. It's not that recent (it was 2010), it wasn't NASA (it was researchers at the University of Sheffield who used data from a NASA satellite), it wasn't sound per se (it was instead sonified data), and ...


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Empirically (I fit a regression on log(mass) vs log(surface temp)), using the table of values in the article on Main Sequence stars, I get a fairly well-fitting formula: $estTemp = 5740*mass^{0.54}$, where estTemp is in C and mass is in multiples of the sun's mass. Seems to work very well for all but the largest and smallest main sequence stars (and not ...



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