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You have a good idea. You mentioned 4 effects already (clock accuracy, latitude, time of year, and clear horizon), but there is another effect that is larger than those: atmospheric refraction. Refraction causes a rising object to appear to be half a degree higher than reality. Refraction depends on atmospheric pressure and temperature, so it may be harder ...

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Asteroids with an orbit of between 1.8 and 2 Au (So their closest approach is is about the same distance to the Earth as the Earth is to the sun) are called Hungaria group asteroids, named after 434 Hungaria. Hungaria itself has an orbit of 1.94 AU, so would be a good example of body. Such asteroids are rather rare. There is a gap in the asteroid belt ...

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The key to this kind of comparisons is to get a ratio. How much bigger is one number than the other? From Buenos Aires to Los Angeles, there are nearly 10,000km. The size of a grain of sand varies a lot, but let's say it's a millimetre in diameter. That's 4 orders of magnitude in the numbers themselves, then three orders of magnitude from there being a ...

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LORRI will be used in 4x4 mode, which yields 4-arcsec pixels. The error in positions is unlikely to be better than 1%, or 40 mas, about 200x larger than Gaia's error. NH has a baseline ~20x larger, but this means it still misses Gaia by ~10x. The date was selected for New Moon to help Earth observers find the two targets. There is no Earth analogue for ...

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Let me see if I can show why your "inverse-square-law means you can't get light from distant sources" intuition is wrong. For the sake of argument let's assume stars really are point sources, and look at how much light you would receive from an infinitely old, infinitely large universe uniformly filled with point-source "stars", each with luminosity $L$, at ...

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The error I think you are making in your "logical" argument is "A light [ie a star] at a distance D1 would a appear as a point of light". If D1 is a star, it would appear as a disc of light. A very small disc, but a disc with a finite and nonzero size. We then add stars at distance D2, D3 etc. Each star covers more of the sky. This is because each star ...

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