Scientists are getting ready to open a treasure chest — three samples of lunar rock and dirt that have never been examined before. They were collected by Apollo astronauts almost half a century ago. But they’ve been stored untouched — waiting for new technology that could reveal more of their secrets.

Astronauts brought 842 pounds of rocks, pebbles, and other materials back to Earth. Most of those samples are stored in a vault at Johnson Space Center in Houston, including the untouched samples.

Researchers have conducted thousands of studies on the Apollo samples, gleaning many secrets about the Moon and about Earth. And the pace of discoveries has quickened in recent years.

About a decade ago, for example, scientists discovered water molecules inside tiny grains of volcanic glass. That suggests that there’s water all across the lunar surface. More recently, they’ve found evidence that the Moon once had a fairly dense atmosphere.

Earlier studies suggested that the Moon was born when another planet hit the embryonic Earth. Debris from the collision came together to make the Moon.

But recent studies have suggested that the picture is more complicated. The size of the other planet, the angle and force of the impact, and other details are still being debated.

Scientists expect to continue studying the Apollo samples for decades to come — learning more secrets about the Moon.

More about lunar exploration tomorrow.

Script by Damond Benningfield