With a good bit of attention focused on space in recent weeks – mainly about the New Horizons probe that has given us a new appreciation for the planet Pluto – I’ve been thinking about the broader idea of exploration, of mankind’s timeless yearning to find out what’s beyond the horizon.

My thoughts keep turning to two of my fellow Carolinians whose lives were cut short by that quest for the unknown, and to an historical figure whose name will be forever linked to the notion of exploration.

Mike Smith and Ron McNair were among the 7 crew members killed when the Challenger space shuttle blew up 73 seconds after launch on January 28, 1986. Smith was the shuttle pilot, McNair was a mission specialist, in charge of scientific experiments on the craft.

The shuttle disaster is seared in our memory. There was a huge television audience for the launch because one of those on board was Christa McAuliffe, the first teacher in space. If you weren’t watching at the time, you’ve seen the video -- the horrific dawning realization that something was going wrong, and then the explosion that scattered flaming debris across the Atlantic.

The space shuttle program was put on hold for almost 3 years after Challenger while investigators pieced together what happened and NASA corrected design flaws. In September, 1988 the shuttle Discovery lifted off on a successful mission. There were some who thought the shuttle program should be scrapped, that human beings should stop trying to explore the hostile environment of space. But the quest for the unknown prevailed, even through another shuttle accident in 2003 that took the lives of the Columbia crew.

Not long after Challenger, NASA launched an unmanned space probe to study Venus, the place in our solar system the most like earth. They named it Magellan, after the 16th century explorer, and I thought it was a fitting name for a venture into uncharted territory.

The original Magellan left Spain with a small fleet in 1519, determined to reach the East Indies by sailing west. That meant he had to find a route around the tip of South America. He did, and it’s named the Strait of Magellan in his honor. Magellan sailed on across the Pacific, becoming the first to navigate it from east to west. It was a perilous voyage. Magellan battled starvation, disease, mutiny, and warfare. In the Philppines, he was killed in a battle with natives. But his second-in-command sailed on, back to Spain, proving conclusively that the earth is round.

Ferdinand Magellan was a resourceful man, determined and often ruthless. In the mold of all great explorers, he was consumed by curiosity – the insatiable hunger to know what’s beyond what we can see. It’s an essential part of being human. Were it not, we would all still be living, elbow-to-elbow, in the place where humanity began. It is an essential part of people like Mike Smith and Ron McNair and Christa McAuliffe. And it will go on, disasters or not, as long as we are unwilling to sit still. We explore earth and sea and sky and space – and the mysterious inner worlds of subatomic particles and nanotechnology -- no matter what the risk, because it is there, beckoning to us.

There are impressive memorials to Mike Smith, in his hometown of Beaufort, North Carolina, and to Ron McNair, in Lake City, South Carolina. But the most fitting memorial to people like them and Ferdinand Magellan, is that we carry on their work. We just won’t give up.

We yearn to know the unknown, even when we put ourselves in peril. Part of the thrill is in the discovery, but maybe the best part is the journey itself.

Robert Inman