The Ares rocket system being developed to loft the shuttle's replacement into orbit has also come under fire.
There is currently some uncertainty over whether the Ares 1 rocket will ever fly.
The proposed Ares I rocket and its crew carrier called Orion are both at an advanced stage.
The officials say the funds currently available to develop Orion and its Ares launch rocket mean the faster timeline is no longer tenable.
It is up to Barack Obama to make a final decision based on the options presented by the panel, but none of the options considered viable includes the default path, the shuttle-derived Ares I rocket and Orion spacecraft, to service the space station.
Yet now that the Shuttle has been scuttled and a proposed Ares I Constellation rocket program has been canceled, other than hitching Russian taxi rides, our astronauts currently have no way to get there and back.
The architecture calls for two new rockets: the Ares 1 to launch crew, and a new heavy-lift rocket known as Ares 5 that could put into orbit the equipment needed by an Orion capsule to travel to the Moon and beyond.
Another rocket, Ares V, would have the capability to launch heavy payloads - service and cargo modules - that would be needed to service Moon missions.
Nasa is due to retire its space shuttles next year and replace them with the Orion spacecraft, an Apollo-like capsule that would launch on a new rocket called Ares 1.
In any case, now that the Space Shuttle has been scuttled and the proposed Ares I Constellation program rocket has been cancelled, NASA has little near-term choice but look to private ventures for Space Station access.
Obama attempted to cancel the government-designed Ares 1 and Ares V super-heavy-lift rocket programs.
Following completion of the current Ares V super-heavy-lift rocket program, the Space Launch System, I believe that the government should commercialize all future launch vehicle development and operations.
The agency is preparing to launch a test rocket that incorporates key features of the new Ares vehicle.
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