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8

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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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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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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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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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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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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Use a constellation map! That will provide much of the information you need. Here are however some things you can try to spot: On the lower left hand side of Orion, you can spot a very bright star, Sirius, in fact the brightest one in the sky. It is part of the constellation Canis Major (great dog). A bit further left and up you probably see a star nearly ...


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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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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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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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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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