|MadSci Network: Physics|
“Could we ever detect a mountain sized mini black hole in our solar system (if they exist)? Will we ever be able to do it? Could we ever detect a large 1 Ton Strangelet in the solar system?” Dear Yevgeniy, These are some great questions! First, the size of a black hole, the radius of its event horizon that is, depends on its mass. If we take a mountain-sized black hole to have an event horizon with a radius of about 5km, then we can use the Schwarzschild radius equation to determine what the mass of the black hole is. The radius in terms of the mass is R = 2 G M / c^2 where G is Newton’s Gravitational Constant and c is the speed of light. Putting M in terms of R we have M = R c^2 / 2G = (5x10^3m) (3x10^8m/s)^2 / 2(6.67x10^-11 N m^2/kg^2) , or M = 3.37x10^30kg . This is about 1.69x the mass of the Sun! This is actually a rather large mass! If a body this massive was floating around our solar system, all of the planets (and the sun) would have their orbits drastically affected and there would be no way that we could miss it. Whether we could detect a smaller black hole would depend on just how small it is, and where it is. The closer the black hole is to another body, the easier it would be to notice irregularities in the body’s motion, and so predict the location the black hole. Another thing that a black hole would do is to bend light around it. If a black hole passed between us and another object, a star or planet for instance, the light from that object would be distorted by the presence of the black hole. If that object was being observed at the time, this distortion could be detected. If the black hole passed close enough to another body to actually draw the body, or some of it, into the black hole, the energy released by the in- falling material would be another way to detect the black hole. A strangelet, a theorized particle of strange matter, with a mass of one ton, would be very small, only about 10-20 microns in size. If it didn’t collide with anything, the best way to detect it would be to notice the gravitational affects that it might have on a near-by object. With a mass of one ton, it would have to be fairly close to the other body, though, to detect its presence. Some people have postulated that some anomalous Earthquakes were actually caused by the Earth being struck by a relativistic strangelet, so we may have already detected them in our solar system! Below are a couple of links that you might look at. They have some more information about strange matter and strangelets that you might find interesting. http://en.wikipedia.org/wiki/Strange_matter http://everything2.com/index.pl?node_id=1068220 Well, Yevgeniy, I hope I have answered your questions to your satisfaction. Please let us know if you would like some more information, with a followon question at the usual MadSci Question Page. Sincerely, Jim Guinn Georgia Perimeter College
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