NASA makes public 45-year-old photos of astronauts in Hawaii

Why did Apollo astronauts train on the lava surfaces of Hawaii? And why NASA still tests equipment in Hawaii.

Before Apollo astronauts went to the moon, they went to Hawaii to train on the Big Island's lunar landscapes.

Now, decades-old photos are surfacing of astronauts scooping up Hawaii's soil and riding across volcanic fields in a "moon buggy" vehicle.

The Pacific International Space Center for Exploration Systems, a Hawaii state agency, is displaying the photos at its Hilo headquarters. Rob Kelso, the agency's executive director, found the images at the Johnson Space Center in Houston.

Astronauts from Apollo missions 13 (1970) through 17 (1972) trained in Hawaii as did some back-up crews, Kelso said.

"The thing that sets Hawaii apart from almost every other place in the world is that it is almost an exact replica of the surface that we see on the moon and on Mars," Kelso told KITV in Honolulu.

Some training was on Mauna Kea volcano, where glacial runoff crushed and refined rock into power. Astronauts also trained on recent lava flows.

Today, robots are tested on the Big Island for moon and Mars missions.

In recent years, engineers have tested technology to pull oxygen out of the island's dirt, which is volcanic basalt like the Martian and lunar soil. Future missions could use this technology to extract oxygen from the land instead of taking it along. The oxygen could be used for breathing, to make fuel or for other purposes.

Kelso said scientists are also interested in testing robots at the Big Island's lava tubes and lava tube skylight holes, which resemble similar formations recently spotted in high-definition images taken by satellites orbiting the moon, Mercury, Venus and Mars.

Lava tubes are tunnels made when lava forms a solid roof after flowing steadily in a confined area for hours. Skylight holes are formed when part of the tube breaks.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.