NASA faces immense challenges. Its shuttle program will end early next year, and the space agency has no clear, approved plan to build the shuttle’s successor.

The International Space Station and its U.S. crew members, along with their partners, are conducting important research in orbit, and NASA must operate and sustain that facility with an intense focus on safety.

Due to inattention and lack of funding by our policy makers, American astronauts next year will be forced to reach the Station via Russian rockets, at least through 2015.

Once the shuttle retires, NASA doesn’t know when U.S. rockets will again launch astronauts from Cape Canaveral., or whether those rockets will be privately run, or government-owned, like the shuttle.

Even less certain are the means for NASA to reach deep space, beyond the space station to the nearby asteroids or the Moon, and when American explorers might be ready for such a journey. Congress and the president have not reached any agreement on a way forward.

NASA’s focus should be on proposing a vigorous, sustainable program of human and robotic exploration, building the means to carry it out, and seeking the support of the public and policy makers to continue American leadership in space exploration, particularly in the inspirational field of human spaceflight.

NASA’s people are properly focused on their technical mission, and I hope NASA’s leaders will follow their example.

Tom Jones is a planetary scientist, four-time shuttle astronaut and Fox News contributor. His book “Sky Walking: An Astronaut’s Memoir,” details the human dimensions of space flight. For more visit www.AstronautTomJones.com.

Fox Forum is on Twitter. Follow us @fxnopinion.