An artist's concept of the Space Launch System on the pad at LC-39B. Image source: NASA.
Lots going on in recent days ...
Work continues on the Space Launch System's Orion crew capsule (AKA Multi-Purpose Crew Vehicle). Florida Today reports that work has begun on the abort motor for the Orion escape system that will be used in an early 2014 test flight.
ATK is developing the main motor for the abort system that would pull an Orion capsule and its astronaut crew away from a rocket in the event of an explosion or other emergency on the launch pad or during launch. The company also is developing smaller abort system thrusters that would steer the capsule into position for the deployment of parachutes that would float a crew to a safe landing back on Earth.
The Salt Lake Tribune, ATK's hometown newspaper, has more on the abort motor.
As for what's below the capsule, SpaceflightNow.com notes that, "NASA must find and purchase a cost-effective, proven cryogenic propulsion system for the first two flights of the agency's heavy-lift Space Launch System because the behemoth rocket's Apollo-era upper stage engine will not be ready in time, officials said."
The clock is ticking for the rocket to be ready in time for its first mission in late 2017. And NASA has a tight budget to pay for the upper stage, which is planned to send humans to the moon on a flight in 2021, according to agency managers.
The Space Launch System's initial missions are expected to dispatch Orion space capsules on flights around the moon and back to Earth. The 2021 launching will carry a crew.
Both flights will be powered into space by cryogenic core stage with three space shuttle main engines, known as RS-25D/E engines, and twin five-segment solid rocket boosters. But development of the J-2X upper stage engine, an upgraded version of a powerplant used on the Saturn 5 rocket, will not be finished in time.
As for potential missions, NASASpaceFlight.com has a potential outline for the first SLS unmanned test flight.
The debut of the Space Launch System (SLS) will send the Orion (MPCV) on a 7-10 day mission to the Moon, with an aim to qualify the Heavy Lift Launch Vehicle (HLV) and Beyond Earth Orbit (BEO) Orion to carry humans into deep space. Exploration Mission 1 (EM-1) involves sending Orion around the far side of the Moon, prior to a splashdown in the Pacific Ocean.
With a launch date of December 17, 2017, the historic mission will aim to hand NASA a Christmas present of becoming a successful pathfinder for crewed flights on the new spacecraft, in turn providing a baseline for a return to exploration in deep space for the first time since the 1970s.
Down the Cape Road at LC-40, Florida Today reports that SpaceX has scheduled a "wet dress rehearsal" for March 1 of the Falcon 9 with the Dragon capsule that is scheduled for its International Space Station demonstration flight in late April.
The simulation at Launch Complex 40 is part of preparations for a NASA demonstration flight that aims to deliver the Dragon to the International Space Station, possibly as soon as late April.
A successful demonstration flight would prove Hawthorne, Calif.-based SpaceX is ready to begin delivering cargo to the station later this year under a $1.6 billion NASA contract.
I received an invitation from a SpaceX representative to attend a media event at LC-40 tomorrow afternoon, however a NASA media credential is required and I don't have one.

This image of the SpaceX Falcon 9 with the Dragon capsule was posted February 25 on the Twitter account of CEO Elon Musk.
UPDATE March 1, 2012 8:15 AM EST — Florida Today calls today's wet test "an important step in preparations for a potential launch late next month."
SpaceX hopes to be ready to launch by late April, but no official target date has been set since the mission was postponed from early February to resolve technical issues.
“We’ll address it whenever they tell us they’re ready,” said Josh Byerly, a NASA spokesman at Johnson Space Center in Houston. “We’re looking forward to a successful rehearsal that will give both SpaceX and NASA even more confidence that they’re headed toward an April launch date.”
Orbital Sciences, the other company with an ISS commercial cargo delivery contract, blames Virginia's spaceport authority for its launch delays. The Delmarva Daily Times reports:
Orbital Sciences Corp. Chief Executive Officer David Thompson blamed delays in the company's Antares rocket project on the Virginia Commercial Space Flight Authority, saying there have been multiple problems in completing the launch pad and associated equipment for the rocket's planned launches from the Mid-Atlantic Regional Spaceport on Wallops Island.
The problems have set the project back eight to nine months, Thompson told investors in a Feb. 21 conference call.
UPDATE March 1, 2012 8:45 AM EST — Not withstanding their delays, Florida Today reports that Virginia hopes to win part of the space launch business — but Florida claims not to see them as a threat.
Virginia Gov. Robert McDonnell signaled his intent to catapult the commonwealth into the highly competitive commercial space marketplace last month at the Federal Aviation Administration’s 15th annual Commercial Space Transportation Conference in Washington, D.C.
With hundreds of industry heavy-hitters in the audience, McDonnell noted that the Mid-Atlantic Regional Spaceport on the eastern shore of Virginia is one of only four spaceports in the nation licensed by the FAA to launch orbital missions. The others: Spaceport Florida, which includes Cape Canaveral Air Force Station and Kennedy Space Center; Vandenberg Air Force Base in California and Alaska Spaceport at Kodiak Island 250 miles south of Anchorage.
An artist's concept of an Orbital Sciences Antares launch at the Mid-Atlantic Regional Spaceport, as it appeared in Florida Today. Original source: Orbital Sciences Corp.
As for programs past, Florida Today reports that the orbiter Discovery is scheduled to depart Kennedy Space Center April 17 for delivery to the National Air and Space Museum in Washington, D.C.
The Smithsonian on Tuesday unveiled plans for four days of “Welcome Discovery” festivities, including the arrival viewing and welcome ceremony, a day of student activities and a “Family Weekend.”
The Smithsonian said Discovery would fly over parts of the D.C. area before landing, but its exact path would not be publicized.
The orbiter is expected to depart KSC around sunrise. A local beach flyover is possible.
Florida Today reports that United Space Alliance appears to have reversed plans for the Shuttle logistics facility in the City of Cape Canaveral off Astronaut Boulevard.
Lead shuttle contractor United Space Alliance pursued new business opportunities, and last fall appeared to have secured a post-shuttle mission servicing military and commercial hardware at the Astronaut Boulevard facility. There was even talk of a new name for the eight-building complex.
But plans changed abruptly when USA’s parent companies, The Boeing Co. and Lockheed Martin Corp., began re-evaluating the joint venture’s future and reportedly directed managers not to sign new contracts.
“USA had come a very long way against daunting odds to crack the defense logistics marketplace and intrigue a number of private sector industrialists with the capability they had,” said Dale Ketcham, a community leader involved in the transition effort. “Unfortunately, at the last minute, Lockheed and Boeing pulled the plug.”
And in closing, a preview of coming attractions ... The House Committee on Science, Space and Technology is scheduled to discuss NASA's proposed Fiscal Year 2013 budget on Tuesday March 7 at 2:00 PM EST. NASA Administrator Charles Bolden will be the sole witness.