The Edison2 is an experimental car that was one of the winners of the ten-million-dollar Progressive Insurance Automotive X Prize.

VOA: special.2010.11.17

It carried the man who became the first human to step on the moon, Neil Armstrong, a former X-15 pilot.

VOA: special.2010.07.07

The first plane ever to fly faster than the speed of sound was the X-1 in nineteen forty-seven.

VOA: special.2010.07.07

The National Osteoporosis Foundation says a test called Dual-energy X-ray absorptiometry,or DXA, is the best test for osteoporosis.

VOA: special.2010.08.31

But he says he felt the greatest satisfaction when a thirteen-year-old painted the word "gun" and then put a big "X" through it.

VOA: special.2009.06.01

One of them,the Apollo-11, traveled to the moon just seven months after the last X-15 flight.

VOA: special.2010.07.07

After a few seconds, when the X-15 was safely away, the pilot started its rocket engine.

VOA: special.2010.07.07

The X-15 was the first major investment by the United States in manned space flight technology.

VOA: special.2010.07.07

In the memorial, there is the X-1, the first airplane to fly faster than sound.

VOA: special.2010.07.07

The first proposal for this new research vehicle, the X-15, was made in nineteen fifty-four.

VOA: special.2010.07.07

They felt the X-15 could have continued to provide new information about aviation and space.

VOA: special.2010.07.07

When he is clear of the B-52, he starts the X-15's rocket engine.

VOA: special.2010.07.07

From under the plane's right wing, the black sharp-nosed X-15 drops free.

VOA: special.2010.07.07

The only tragedy connected with the X-15 program happened in nineteen sixty-seven.

VOA: special.2010.07.07