A balloon is sent aloft with a solar collector, and it sends the electricity produced down to the ground via an electrical cord. The balloon is a hybrid—it stays aloft with a mix of air and helium.

"The balloon could be controlled remotely by an operator on the ground," she says. "They'd be able to raise or lower the altitude of the balloon so that it could pick up different wind currents ...

After careful analysis, U.S. military commanders determined that shooting down the balloon while it was above the ground posed an unwarranted risk to people (...) due to the size and altitude of ...

Did they just send the Olympic cauldron up into the Paris skies in a hot-air balloon? IS the cauldron a hot-air balloon? Will it just float around there in the sky for two weeks? If you watched ...

Nothing quite compares to witnessing a mass ascension at dawn, when hundreds of colorful hot air balloons lift off the ground and fill the sky above. But the fun of hot air balloon festivals doesn ...

But we don't actually fill up the entire volume of the balloon on the Earth or on the ground because as the balloon rises in the atmosphere, it'll expand... CHANG: Oh. REED: ...Until it fills that ...