Florida Today reports NASA will release the Space Launch System design today at a 10:00 AM EDT press conference in Washington, D.C.
Critics have dubbed the project the "Senate Launch System," which would explain this passage:
NASA Administrator Charles Bolden will detail the plan in a 10 a.m. news conference on Capitol Hill with U.S. Sens. Bill Nelson, D-Fl., and Kay Bailey Hutchison, R-Texas, two big backers of the project.
According to Florida Today reporter Todd Halvorson, "There will be a booster contract competition that will be based on cost and performance requirements," which in my opinion is certain to displease the Utah congressional delegation.
As I wrote yesterday, Utah senior senator Orrin Hatch recently circulated a letter on Capitol Hill demanding the SLS design be released immediately, and that it use solid rocket boosters. Those boosters would be designed by ATK's Utah division, naturally.
I speculated that yesterday's press conference announcing an agreement between NASA and ATK to develop the solid-based ATK Liberty commercial crew vehicle might be a sop for the Utah congressional delegation. The announcement of a potential SLS design with liquid boosters one day after the ATK press conference does seem coincidental, to be charitable.
UPDATE September 14, 2011 9:00 AM EDT — The Orlando Sentinel reports:
After months of debate, NASA has settled on plans for its next spaceship — a space shuttle hybrid that will fly twice in the next decade and cost $30 billion through 2021, according to senior administration officials and internal NASA documents.
The Sentinel article also indicates a compromise on the solid/liquid booster competition:
... [T]he twin boosters for the new rocket, at least initially, would be the same shuttle boosters built by Alliant Techsystems of Minnesota.
NASA intends to hold a competition in the years ahead for the boosters. The administration official said NASA definitely would use the ATK boosters for the 2017 launch but that it could have the competition complete in time for new boosters in 2021.
So it appears the first flight's boosters are intended to appease the Utah congressional delegation, while the second flight's boosters will appease the California and Alabama delegations that wanted open competition. Sound science has nothing to do with it.