At NASA, 2008 will be remembered for shuttle missions, discoveries on Mars, and mysteries revealed across the solar system and beyond. While looking back at the U.S. space agency's 2008 successes, VOA looks at the agency's uncertain future and its plans to bring humankind to Moon.
NASA's Constellation project is accelerating, with engineers building and testing rockets and capsules that will be the primary vehicles for human space exploration after the shuttle fleet is retired in 2010.
The core of NASA's current activities is a return to the moon, with astronauts landing there by 2020.
Meanwhile the International Space Station has been racing towards completion.
In February, the Shuttle Atlantis blasted off on the first of four missions to the space station. In 2008, repairs and upgrades doubled the station's crew capacity. Two major science labs were delivered.
In 2009, a new solar wing - to generate energy - will complete major additions.
In 2008, NASA's unmanned probes caught the public's attention. Three around the sun began sending data and the first ever three dimensional images of the star.
The Cassini spacecraft passed through Saturn's rings and turned its instruments on one of the planet's moons, analyzing icy geysers that erupt from its interior.
The MESSENGER probe flew by the planet Mercury twice, mapping its surface.
The fascination with Mars grew with six spacecraft exploring the red planet.
For many, the most exciting moment came when the unmanned probe Phoenix completed its 10-month journey, landing on the red planet in May.
The probe dug into the planet's surface and confirmed the presence of frozen water, a sign there could have been life on Mars at some time in the past.
The Hubble Space Telescope continued to focus on distant worlds, bringing images of colliding galaxies and more. 2008 will be remembered for Hubble's gift of the first ever image of a planet outside our solar system.
Despite budget uncertainties, eight shuttle missions, almost all to the space station, are planned before the fleet is retired.
NASA's long term plans are to build a permanent base on the moon that may one day be used as a launching pad for manned flights to Mars.