Far below sea level, they contain some of the harshest environments on Earth, with no oxygen and no light.

VOA: special.2010.11.10

No one knew if they could get the spacecraft back to Earth, or if they could survive long enough to return.

VOA: special.2009.07.22

Whether grown naturally or through technology, people who love orchids say they are the most beautiful flowers on Earth.

VOA: special.2010.04.06

University of California biologist Bill Schopf studies ancient fossils and the dirt they are found in on earth.

VOA: special.2010.05.25

They left a pathway of great rocky openings in the earth that extend for hundreds of kilometers.

VOA: special.2009.10.07

They also showed that the Apollo spacecraft could survive the launch and could re-enter Earth's atmosphere safely.

VOA: special.2009.07.08

They needed to change their flight path to take them around the moon and back toward Earth.

VOA: special.2009.07.22

They appear blue. Observations of forty-six galaxies showed Hubble that the galaxies were traveling away from Earth.

VOA: special.2009.04.29

And,as they talked, could see pictures of the moon people on Earth on their television sets.

VOA: special.2009.07.08

They said hot melted material flows up from deep inside the Earth through the split.

VOA: special.2010.01.12

They collected more than thirty kilograms of rock and soil to take back to Earth.

VOA: special.2009.07.15

They moved easily and quickly, because the moon's gravity is six times less than Earth's.

VOA: special.2009.07.15

And they placed a small satellite in lunar orbit before they returned to Earth.

VOA: special.2009.07.29

They are set into the earth. They meet to form a wide V.

VOA: special.2009.05.25

They had to design, build and program robots to explore the Earth's climate.

VOA: special.2009.04.24

They are the reason for the many different kinds of life on Earth.

VOA: special.2009.12.01

Or,they say the Earth may be warming, but human activity is not responsible.

VOA: special.2010.01.19

It is as if they are the one and only person on Earth.

VOA: special.2010.09.12

After they land,meteorites can pick up small organisms and chemicals from Earth's environment.

VOA: special.2011.06.22

Then they returned to the orbiting command module and started back to Earth.

VOA: special.2009.07.29

They include "The Day the Earth Stood Still" and "Breakfast at Tiffany's."

VOA: special.2011.02.27

They left five scientific instruments designed to send information back to Earth.

VOA: special.2009.07.29