New technology reduces noxious emissions . Miniature unmanned planes descend on arctic for research . Findings may boost efforts to destroy pollutants with ultrasound . Once discarded fly ash now being used to clean contaminated water at Temple University laboratory . Earthquake magnifier can turn a distant tremor into a disaster on your doorstep .
Synthetic clay removes radium from water and soil .
Small streams important in controlling nitrogen . Movement of Earth's crust can now be detected using GPS . A spread of a different kind . NASA may soon help scientists do a better job of tracking pollution . Dobson's research leads to prehistoric theory .