WASHINGTON -- NASA has long been hungry to put the Earth in an astronaut's rear view mirror. Today the agency finds itself embroiled in the sticky business of sorting out the financial, technical and scientific woes resident within the multi-billion dollar International Space Station (ISS) program.

Putting that turmoil aside, the space agency has quietly scripted a step-by-step plan to send astronauts to locales between Earth, the Moon and the Sun, to Mars and the asteroids, and even farther -- to the moons of several outer planets.

This suite of far-out space missions beyond Earth's orbit was assembled as a NASA strategic plan for the Human Exploration and Development of Space (HEDS).

The images accompanying this story were commissioned by NASA from John Frassanito & Associates to illustrate the proposals.

It is clear, however, until the ISS effort is under cost and managerial control, NASA's escape velocity vision will remain in limbo. Furthermore, the space agency's new chief, Sean O'Keefe, sees as priority one getting the ISS effort under control. But as part of this futuristic plan, new artwork was created specifically to highlight what NASA officials consider as viable steps in human space exploration.

Beyond Earth's orbit, 100-day class missions would send crews on missions to Earth-moon and Earth-Sun "libration points." Also known as L-points, these locales are where gravitational forces balance.

At these outposts, humans could maintain revolutionary new telescopes and build up the hardware to further explore the lunar surface.

Extending the human experience even farther, 500 to 1,000-day missions would integrate human and robotic abilities to explore the Mars system, as well as asteroids.

This class of human exploration mission would be staged within 2 astronomical units (AU) of the sun. One AU is defined as the Earth's average distance from the sun -- about 93 million miles (150 million kilometers). Travelling within this region, access to numbers of asteroids become feasible.

Lastly, missions of 2,000 days and longer are called for in the NASA plan. Human treks outward to Titan could be attempted.

How soon are these missions plausible?

According to NASA study groups, for the midterm, 100-day mission duration flights were projected for the 2006 to 2011 time frame. Missions lasting 500 to 1,000 days are seen as the far-term, starting in 2012.

For 2,000 days and longer voyages to outer-solar-system targets, those voyages were tagged "beyond" the far-term.