Stellar parallax clarification | Cosmology & Astronomy | Khan Academy
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Comments
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theta
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Since we use only teta for the calculation, why do we need to find the same teta value twice.? Maybe this is related to the parallax, but I am not able to comprehend, why we need to measure the same teta twice. Thanks Sir.
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How do you know when the point is that the angle is a right angle
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Lovin the vids so far
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@fbrandse Oh yes he did, this is the 3rd Parallax video, in the first he mentions the close/distant object comparison. In this case the shift in position of the nearby star is the Sun in 6 monthly positions and the other star is the target star.
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the 3ds uses parallax to work btw
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I don't think this video is a good explanation of what the method of parallax in measuring stellar distances really is. The whole idea of parallax is the apparent shift in position of some nearby star with respect to another star that is supposedly further away. In your video and the previous one you make no mention at all of this comparison star. You just assume that it is possible to directly measure the angle theta, but stars are way too far for that.
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@jerktrucker The triangle with the 90 degree angle is the triangle that consists of one of the sides of the isosceles triangle and the perpendicular bisector of the base of it--essentially half the triangle. The reason why he measures it six months apart to see if those two angles are the same is to make sure that that triangle is isosceles so that when he cuts it in half, it'll be a right triangle.
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Sir I loved your video but I have a question. I have heard that measuring the distance to a star using the paralax method is limited to about 70 to 100 lights years. Do you agree and if not, how far can we measure using this method? Also I was wondering how we arrive at measuring distances in the thousands or millions of light years when it seems like we would not live long enough to recieve that data. Thank you.
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