Transcript for Two sisters to work with NASA during solar eclipse
persons of the week. The great American eclipse is now just three days away. Millions of Americans descending on towns and parks across the country to see it. Tonight, two young sisters, and their invention that even nasa will rely on. We've chosen them as our persons of the week. Kimberly and Rebecca Yeung from Seattle, Washington, in their garage two years ago, building their own mini lightweight spacecraft. Our goal was to launch it into space. Or at least as close to space as we could get. Reporter: Trial and error even styrofoam in case of a water landing. And then the day arrived. There's dad Winston. It was really cool to see how the Earth looked from up there. It made us think about how small we are. Our spacecrt got up to 78,000 feet. That's 2 1/2 times the height of mount Everest. Reporter: Their spacecraft flying high. And that's a picture of their cat, loki, flying high. At the time the white house so impressed, they got an invite from president Obama. What was that like when your dad got the call? Could your family believe it and what did you tell the president when you got there? When dad got the call, it was the day before April fools' day. And the call was something like, hi, it's the white house speaking. And dad said something like, April fools' day is tomorrow. Reporter: They went to the white house and showed off their invention. And this week, they'll be in glendo, Wyoming, in the path of totality. And their data, they're going to share with nasa. What do they want to be when they grow up? I wanted to be robotic engineer. Reporter: Her older sister not sure yet. But she does have advice for other girls their age. Don't give up, just keep on going and persevere, keep on trying. Our coverage of the eclipse begins at 1:00 P.M. Eastern. Rob, how is it looking as far as cloud cover? Coast to coast, clear skies will be ideal. But look at the graphic, the brightest white line, the path of totality. Lincoln, Jefferson city, just fair. Charleston, may have the most cloud cover. I'm going to work on it, clear things up by Monday, rob. 1:00 P.M. Eastern on Monday. Set your DVRs at home if you can't watch it with us live. I'm David Muir. Thanks for watching this week. As I mentioned, the great American eclipse, Monday at 1:00
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