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At thought at first that the title was clickbait. " You mean to tell me that we can see light from the edge of the universe, but we can't tell if an object wil
by IG_Semmelweiss 2y ago
At thought at first that the title was clickbait.
" You mean to tell me that we can see light from the edge of the universe, but we can't tell if an object will be bright (or not) when it arrives at earth ? "
Reading the article, it seems that there's materiel that will react with the faint but steady hit of sunrays. Still , with our tech and advancement, you'd think we would be able to give a reasonably accurate prediction of whether a a very large stone will continue to shine bright when it passes by earth at supersonic speeds.
- ethbr1 2y ago"I have an object composed of unknown materials, jumbled together in an unknown way, with unknown density. I'm going to hold it next to a light and heat source. How bright would it be?" That sounds like a difficult problem.
- deadbabe 2y agoNot really. You just need good data or approximations of the data. Then just compute.
- macksd 2y agoYeah, let's just measure the density and composition of a comet that will be here in a few months, and with expectations that it may be releasing new gaseous formations as it gets closer, predict what will happen with those formations. Let me just code that up real fast.
- deadbabe 2y agoYou can literally measure anything, that’s not the same as being 100% precise. That’s how it works.
- ethbr1 2y agoThe difference is compounding, unstable systems. In much simpler form, it's similar to the "Where will this satellite in a decaying orbit land?" The difficulty is not the approximation: the difficulty is that whether drag begins to increase at t=x or t=x+30sec (based on orientation when it first encounters atmosphere) cascades throughout the rest of the equations and dramatically changes the results.
- deadbabe 2y agoMonte Carlo it
- mbwgh 2y agoElon is it you?
- yencabulator 2y agoThe "unknown" part implies lack of data. We literally don't know what gases, and how much of them, will evaporate off of it until they do evaporate. And that doesn't happen until it warms up more.
- deadbabe 2y agoWe can estimate.
- yencabulator 2y agoThe current data gives estimates between "brighter than stars" and "not visible without instruments".
- phyzome 2y agoA big part of the question is whether it will still be offgassing enough to produce a bright coma.
- malfist 2y agoIt all depends on how much ice is in the comet.
- konstantinua00 2y agoit's not the stone that shines, but cloud around it and we can't even precisely predict cloud formation more than week or two in advance right in our face - on Earth so no wonder comets are unpredictable