NASA TV has confirmed that touchdown has occurred and the three ISS crew members are back on Earth.

NASA announced today that it will hold a media teleconference tomorrow, May 24, to “discuss a major agency decision that will define the next transportation system to carry humans into deep space.”

NASA’s plan for a new crew space transportation system has been a point of contention between Congress and the Obama Administration since the President’s decision last year to rely on the commercial sector, not NASA, to build whatever systems will be used to get people to and from low Earth orbit (LEO) and the International Space Station (ISS).

Congress grudgingly went along with the Obama plan in the 2010 NASA Authorization Act with the caveat that NASA must build a large launch vehicle capable of taking 130 tons to LEO (a “heavy lift launch vehicle” or HLLV) to enable human exploration to more distant “beyond LEO” destinations. The NASA-developed system also would serve as a backup to the commercial systems for access to LEO if they do not materialize or fail.

The Obama plan was for NASA to spend several years developing technology for an HLLV, but not to decide on a design until 2015. The language in the law directs NASA to proceed immediately on a new HLLV and many members of Congress who are deeply involved in NASA issues have been very critical that NASA is not adhering to the law. NASA Administrator Bolden has made clear that he wants to start with a less capable launch vehicle that could someday evolve into the 130 ton class vehicle Congress desires. How much mass the HLLV can launch is a critical component of planning for whatever destination lies beyond LEO for U.S. human spaceflight.

NASA submitted an interim report to Congress about its plans for the HLLV, or Space Launch System as it is called in the law, and for a Multi-Purpose Crew Vehicle (MPCV), or spacecraft, for the astronauts that the law also requires. NASA’s report was not well received primarily because it warned that none of the designs it had looked at could be developed and built on the time scale required and for the amount of money authorized by the law.

The media teleconference begins at 3:30 pm EDT. Audio will be streamed at NASA’s newsaudio website.

The following events may be of interest in the week ahead. For more information, check our calendar on the right menu or click the links below. Congressional schedules are subject to change; check the relevant committee’s website for up to date information.

During the Week

The House and Senate are in session this week. The House is expected to consider the FY2012 National Defense Authorization Act; the House Rules Committee is expected to vote on the rule for the bill on Tuesday.

The House Appropriations Committee is expected to begin marking up FY2012 appropriations bills this week, but the two that fund most of the government’s space programs — Defense and Commerce-Justice-Science — are not on the docket this week.

May 25 is the 50th anniversary of John F. Kennedy’s speech to Congress that set America on the path to land men on the Moon. Various invitation-only events are scheduled; let us know if you know of any public events!

Tuesday, May 24

• NASA Aerospace Safety Advisory Panel, NASA Headquarters, Washington DC, 11:00 am – 1:00 pm EDT

Wednesday, May 25

• NASA Advisory Council Science Committee Task Group on Analysis Groups, virtual (telephone and WebEx), 2:00-4:00 pm EDT

Wednesday-Friday, May 25-27

• National Research Council Decadal Survey on Solar and Space Physics (Heliophysics), Panel on Solar and Heliospheric Physics, Boulder, CO

Thursday, May 26

• FAA Public Meeting on Regulatory Approach for Commercial Orbital Human Spaceflight, Cocoa Beach, FL
• House Intelligence Committee markup of FY2012 Intelligence Authorization Bill, room HVC-304 U.S. CapitOL, 10:00 am EDT
• House Science, Space and Technology Committee’s Space and Aeronautics Subcommittee Hearing on Commercial Cargo, 2318 Rayburn House Office Building, 10:00 am EDT

As the Endeavour crew continues its tasks while docked with the International Space Station (ISS), the ISS crew will be executing a crew rotation, with three members of the ISS crew departing the ISS while the shuttle is there.

Russian Dmitry Kondratyev, American Cady Coleman, and Italian Paolo Nespoli will undock and return to Earth on May 23 aboard their Soyuz TMA-20 spacecraft while the shuttle is still docked with the ISS.

This is the first time NASA and its Russian counterparts have approved the use of “Dual Docked Operations” (DDO). The associated challenges are described on NASASpaceflight.com. They range from technical issues involving proximity operations to asynchronous sleep cycles for the ISS and shuttle crews.

Delays in the launch of Endeavour and to the launch of Soyuz TMA-02M with its replacement ISS crew members necessitated the decision to approve this unusual procedure. Soyuz TMA-02M is now scheduled for launch on June 7 EDT (June 8 Moscow Time) with Russian Sergey Volkov, American Michael Fossum, and Japanese Satoshi Furukawa. They will arrive after the shuttle has departed; it is scheduled to land on June 1.

Meanwhile, the Endeavour crew successfully installed the Alpha Magnetic Spectrometer (AMS) particle physics experiment on the ISS starboard truss this morning.

The top Democrats and Republicans on the Senate Commerce, Science and Transportation Committee sent a letter to NASA Administrator Charlie Bolden today criticizing the agency’s implementation of the 2010 NASA Authorization Act.

The chairmen of the full committee and of the Science and Space Subcommittee, Sen. Jay Rockefeller (D-WV) and Sen. Bill Nelson (D-FL) and their Republican counterparts, Sen. Kay Bailey Hutchison (R-TX) and Sen. John Boozman (R-AR) charged that NASA “has not made sufficient progress in carrying out the changes” required by the 2010 NASA Authorization Act and “has not adequately complied with a number of reporting requirements” in that Act.

The five-page letter goes on to detail the Senators’ concerns about the pace with which NASA is proceeding with the direction in the law to build a new crew transportation system and requests that a senior agency official “who has first hand knowledge of NASA’s efforts to implement policy changes” in the law brief them every two weeks beginning the week of May 30, 2011. It then requests specific information about the reports that were required by the law, such as the names of the senior NASA officials(s) responsible for preparing, reviewing and approving them, various related studies that were “purportedly” presented to NASA while the reports were underway, and copies of all documents and communications, including emails, discussing different aspects of the reports.

The Senators also request very specific information about NASA’s work on the Multi-Purpose Crew Vehicle and Space Launch System required by the Act.

The subcommittee held a hearing today on the relevance of the space program to national imperatives. During the hearing, Sen. Hutchison, in particular, voiced continued concern that NASA is not implementing the law. A SpacePolicyOnline.com summary of the hearing will be posted soon.

Next week, a House subcommittee will hold a hearing on whether the companies that intend to provide commercial cargo services for the International Space Station will be ready to fulfill that role.

On May 26, the Space and Aeronautics Subcommittee of the House Science, Space and Technology Committee will hear from NASA, GAO, and the two companies that plan to offer commercial cargo services, SpaceX and Orbital Sciences. The topic is “NASA’s Commercial Cargo Providers: Are They Ready to Supply the Space Station in the Post-Shuttle Era?” Bill Gerstenmaier, NASA’s Associate Administrator for Space Flight, will represent the agency. Gwynne Shotwell and Frank Culbertson will be there on behalf of SpaceX and Orbital, respectively. Cristina Chaplain will testify for the Government Accountability Office (GAO).

The hearing starts at 10:00 am EDT in 2318 Rayburn House Office Building.

The Senate Commerce, Science and Transportation Committee has posted the witness list for tomorrow’s hearing on Contributions of Space to National Imperatives.

The witnesses are:

• Elliot Pulham, Space Foundation
• Frank Slazer, Aerospace Industries Association
• Chris Chyba, Princeton University
• Frank Culbertson, former astronaut (he is currently with Orbital Sciences Corp.)

The hearing is at 10:30 am in 253 Russell Senate Office Building.

NASA’s press conference about the Endeavour launch is just starting. Watch on NASA TV.

The STS-134 mission is underway. Space Shuttle Endeavour lifted off on schedule at 8:56 am EDT and is now in orbit. A post-launch press conference is scheduled for no earlier than 10:00 am EDT. It can be watched on NASA TV.

The following events may be of interest in the week ahead. For more information, check our calendar on the right menu or click the links below. Times, dates and witnesses for congressional hearings are subject to change; check the committee’s website for up to date information. The House is in recess this week; the Senate is in session.

Monday, May 16

• Scheduled launch of Space Shuttle Endeavour, 8:56 am EDT. Watch on NASA TV.
• National Research Council (NRC) Committee on NASA Technology Roadmaps, Panel on Materials, NRC Beckman Center, Irvine, CA, open sessions 10:15 am – 1:30 pm PDT.

Tuesday, May 17

• NASA news conference on upcoming Aquarius mission, NASA Headquarters, Washington, DC, 1:00 pm EDT

Wednesday, May 18

• Senate Commerce Committee Hearing on Contributions of Space to National Imperatives, 253 Russell Senate Office Building, 10:30 am EDT (as listed in the National Journal’s Daybook)
• CSIS meeting on GPS and Lightsquared, 1800 K Street, N.W., Washington, DC, 2:00-3:30 pm EDT

Wednesday-Friday, May 18-20

• NRC Committee on Human Spaceflight Operations, NRC Jonsson Center, Woods Hole, MA. Open sessions are on May 18 from 1:15-6:15 pm EDT.

Wednesday-Sunday, May 18-22

• International Space Development Conference 2011, Huntsville, AL

Friday, May 20

• Marshall Institute and Space Enterprise Council seminar on The Emergence of U.S. National Space Policy: Considering Space Policy Development from Carter to Obama, TechAmerica, 601 Pennsylvania Ave,. NW, Suite 600, Washington DC, 9:00 am – 12:00 pm