NASA has approved a $59.8 million project to study the distribution of the Earth's forests using a multibeam laser. The study is part of NASA's ambitious Mission to Planet Earth, a multipronged plan to improve the accuracy of geophysical measurements that are derived from satellite observations. The space agency plans to launch in the years 2000 and 2001 two small satellites that will be equipped to provide the first standing count of the Earth's trees. In addition, the satellites will assess tree heights and the Earth's overall forest canopy structure 10 times better than possible before, the agency said.