The failed Skylab will come screaming home to the earth in disappointment sometime next month, but we don't know where it will fall. That precise  information is beyond even the calculations of scientist and their computers.   The best they can tell us is that the space station, weighting 77 tons and as high as a 12-story building, will break into hundreds of pieces that will be scattered  across a track 100 miles wide and 4,000miles long.   We are again exposed  to one of those unexpected adventures, or misadventures, of science that attract our attention from the boring routines of daily existence and encourages us to think a lot about man's future.   What worries Richard Smith, the Skylab's director, is the "big pieces" that will come through the atmosphere. Two lumps, weighing 2 tons each, and ten, weighing at least 1,000 pounds each, will come in at a speed of hundred of miles an hour, and if they crash on land they will dig holes up to 100 feet deep.   What worries us, with our lack of scientific knowledge and our quick imagination, is both the big and little pieces, although project officials say there is a very small chance that anyone will be injured by them.   That's good to know, but it doesn't remove the doubt of the millions who still remember the nuclear accident at Three Mile Island. That accident took place in 1979 in spite of what scientists had assured(...) us as to the safety of the nuclear reactor . The broken Skylab will come into view   _  .
in two lumps---- one weighing 2 tons and the other weighing 10 tons falling with the force of a 12-story building as 12 bigger pieces and hundreds of smaller pieces as an attractive scene to millions of people