Keith's 11:00 am EDT note: Sources are reporting that the Senate Commerce Committee has finally made good on its threat and has issued a subpoena to NASA regarding materials related to the SLS decision. Prior to this several letters and a hearing were held to prompt NASA in this regard. No luck. Congress is more or less convinced that the decision regarding SLS design/architecture has already been made and they are using the tools at their disposal to force NASA/the White House to admit that this is indeed the case. Stay tuned.
Keith's 1:00 pm EDT note: According to NASA PAO "While we share the Senators' commitment to human space exploration and implementation of the Authorization Act, we also have a commitment to be responsible stewards of taxpayer dollars. The Space Launch System is the most important -- and expensive -- decision NASA will make for the next decade, and we want to get it right so we don't repeat the mistakes of the past or get pushed into making a premature decision about our nation's deep space exploration plans."