On Thursday President Obama will announce his plan for NASA's human space flight program, which is expected to ground the agency's massive Constellation flight program. Obama is taking serious flak for the policy from no less than Neil Armstrong, the first human to set foot on the moon. At 79 years old, Armstrong rarely uses his famous name to intrude upon public debates. So his dissent, in an open letter co-signed by Apollo 17 commander Eugene Cernan and Apollo 13 commander James Lovell, is making waves. Here are excerpts from the letter calling Obama's space plan "devastating."

The availability of a commercial transport to orbit as envisioned in the President’s proposal cannot be predicted with any certainty, but is likely to take substantially longer and be more expensive than we would hope.

For The United States, the leading space faring nation for nearly half a century, to be without carriage to low Earth orbit and with no human exploration capability to go beyond Earth orbit for an indeterminate time into the future, destines our nation to become one of second or even third rate stature. While the President's plan envisages humans traveling away from Earth and perhaps toward Mars at some time in the future, the lack of developed rockets and spacecraft will assure that ability will not be available for many years.

Without the skill and experience that actual spacecraft operation provides, the USA is far too likely to be on a long downhill slide to mediocrity. America must decide if it wishes to remain a leader in space. If it does, we should institute a program which will give us the very best chance of achieving that goal.
The whole letter is here. This isn't the first time prominent moon-walkers have publicly split with the current administration. Armstrong's fellow Apollo 11 crew member Buzz Aldrin recently opined that Obama was not doing enough to further a manned mission to Mars.

Update
: Aldrin supports the president on his recent plan. "Today I wish to endorse strongly the President’s new direction for NASA," he writes.