Hal Moseley was a Human scientist on Penthara IV. In 2368, he enlisted the help of the USS Enterprise-D when the planet was threatened by environmental changes caused by an asteroid that hit an uninhabited part of the planet. A nuclear winter was a possibility. Geordi La Forge and Data tried to help with the problem. At first the Enterprise-D used phasers to release gas into the atmosphere to counter the effects of the nuclear winter. However, this only caused more damage, as the planet was hit with a series of earthquakes.