"This valley of history has seen mankind complete its first evolutionary steps into the universe: leaving the planet Earth and going forward into the universe.

VOA: special.2010.04.28

Yes. This cannot depend on the planet Earth.

没错,这个问题不能依赖于地球

耶鲁公开课 - 基础物理课程节选

Also left forever on the moon is a sign with these words: "Here men from the planet Earth first set foot on the Moon July,nineteen sixty-nine A.D.

VOA: special.2009.07.15

A new report says mangrove forests store more planet-warming carbon dioxide than almost any other ecosystem on Earth.

VOA: special.2011.05.10

Water exists on Earth and the planet Mars.

VOA: special.2009.09.30

He called the planet "Spaceship Earth."

VOA: special.2010.05.30

On the the 40th anniversary of Earth Day, this warming planet we live on is posing serious new challenges to human civilization: increasingly severe droughts, floods,and storms across the globe, and slowly rising ocean levels.

VOA: standard.2010.04.21