He heads an environmental group in Florida called One Village Planet that works in Ghana and Haiti.

VOA: special.2009.06.29

You bring iron ore from one part of the planet, carbon, limestone, you put it into this reactor and you ship this all over the world.

你得到钢铁从地球的一个地方，还有碳，石灰岩，将它们放入这个反应器,你将它运送到世界各地。

麻省理工公开课 - 固态化学导论课程节选

One involves landing on the surface of the planet Mercury.

VOA: special.2010.05.25