But one thing is sure. The discoveries in the meteorite helped shape policy and exploration efforts at the United States space agency,NASA.

VOA: special.2010.07.28

"I thought that sooner or later one thing was sure to happen: The first real test once he was through school would ruin him.

VOA: special.2009.01.03

I thought that sooner or later one thing was sure to happen: The first real test once he was through school would ruin him.

VOA: special.2010.03.27

But one thing is sure: the effects on your health are just as great.

VOA: special.2010.06.08

And yet,they were sure they had done the right thing.

VOA: special.2010.01.28

So,basically,that's how I started. Sometimes I'm not sure if I've done the right thing or not."

VOA: standard.2010.07.20

"People can do things in their own lives, with their children, they can do work in their communities to improve it and once you take those steps, the next logical step is to make sure that your government officials are doing the right thing."

VOA: standard.2010.04.25