Secretary of the Treasury Tim Geithner announced this morning that the United States has reached the legal limit of how much debt it can incur. Just weeks ago, the imminent breach of the $14.3 trillion debt ceiling was the source of political angst in Washington, but Geithner is keeping the government solvent until August 2 by not contributing the government’s share to certain government retirement accounts.

In a letter to Congress, Geithner notified the congressional leadership that Treasury will not “invest fully” in the Civil Service Retirement and Disability Fund or the Government Securities Investment Fund (the “G” Fund) of the Federal Employees’ Retirement System. He said those accounts would be “made whole once the debt limit is increased.”

He stated that, as required by law, he has determined that a “debt issuance suspension period” begins today and will run until August 2, by which time he hopes Congress will have raised the debt limit.

Democrats and Republicans are far apart, or close to agreement, on how to deal with the deficit depending on who is speaking at any particular moment in time.

Space Shuttle Endeavour remains on schedule for launch at 8:56 am EDT tomorrow, Monday, May 16. The STS-134 mission is Endeavour’s last. Its April 29 scheduled launch was delayed because of technical problems that have been resolved.

The 16-day mission will take the Alpha Magnetic Spectrometer science instrument and other equipment and supplies to the International Space Station (ISS).

Only one space shuttle mission remains after this one, the launch of Atlantis (STS-135). A tentative launch date for Atlantis has been June 28, but because of the delay to STS-134, STS-135 is expected to slip as well.

May 16 it is! NASA has announced that space shuttle Endeavour will launch on May 16 at 8:56 am EDT. This is the final launch of Endeavour on its STS-124 mission.

The following events may of interest in the coming week. For more information, check our calendar on the right menu or click the links below. Times, dates and witnesses for congressional hearings and other activities are subject to change; check the relevant committee’s website for up to date information.

During the Week

The House is in session Tuesday-Friday and is scheduled to debate the FY2011 Intelligence Authorization Act (H.R. 754) on Thursday and Friday. The Senate is in session Monday-Friday.

Monday, May 9

• NASA news conference on progress of repairs to space shuttle Endeavour, Kennedy Space Center, FL, 3:00 pm EDT (watch on NASA TV)

Monday-Thursday, May 9-12

• International Academy of Astronautics Planetary Defense Conference: From Threat to Action, Bucharest, Romania

Tuesday-Wednesday, May 10-11

• FAA Commercial Space Transportation Advisory Committee (COMSTAC), National Housing Center, 1201 15th St., NW, Washington, DC
  • Tuesday, working group meetings, 8:00 am – 5:00 pm EDT
  • Wednesday, meeting of full committee, begins at 8:00 am EDT
• NASA Advisory Council (NAC) Planetary Protection Subcommittee, NASA Headquarters, Washington DC
  • Tuesday, 9:00 am – 5:00 pm EDT, room 5H45
  • Wednesday, 9:00 am – 1:00 pm EDT, room 9H40

Wednesday, May 11

• House Armed Services Committee full committee markup of FY2012 National Defense Authorization Act, 2118 Rayburn House Office Building, 10:00 am EDT
• Senate Armed Services Strategic Forces Subcommittee hearing on Military Space Programs, 106 Dirksen Senate Office Building, 2:30 pm EDT
• AIAA Spotlight Awards Gala Dinner, Ronald E. Reagan Building, Washington DC, 6:30 pm EDT

Wednesday-Thursday, May 11-12

• NAC Earth Science Subcommittee meeting, NASA Headquarters, Washington DC, room 3H46
  • Wednesday, 8:30 am – 4:00 pm EDT
  • Thursday, 8:30 am – 2:30 pm EDT

Thursday, May 12

• Senate Appropriations Transportation-HUD Subcommittee Hearing on FAA’s FY2012 Budget Request, 138 Dirksen Senate Office Building, 9:30 am EDT
• House Foreign Affairs Committee Hearing on Export Controls, 2172 Rayburn House Office Building, 10:00 am EDT

NASA has set May 16 as the newest “no earlier than” launch date for space shuttle Endeavour (STS-134). It also extended the mission, once it launches, from 14 to 16 days.

The agency said that launch opportunities continue through May 26, with May 21 as the only day when it cannot launch. If it did, its arrival at the International Space Station on May 23 would conflict with the departure of three of the Expedition 27 crew members who are due to return to Earth that day. NASA said that it determined that all of Endeavour’s tasks could be accomplished with only three ISS crew members aboard.

A news conference will be held on May 9 at 3:00 pm to discuss the progress of repairs to the Launch Control Assembly that failed and scrubbed the April 29 launch attempt. NASA TV will cover the news conference live.

NASA is expected to set a new launch date for space shuttle Endeavour (STS-134) Friday afternoon.

A post on NASA’s shuttle website states that “Endeavour’s no earlier than launch date remains May 10, but senior NASA managers will meet Friday to evaluate the progress of repairs and select a new launch date for the STS-134 mission to the International Space Station.” Technicans are replacing a faulty Load Control Assembly needed for the shuttle’s Auxiliary Power Units that control hydraulic systems that steer the vehicle. This mission was intended to launch on April 29.

Commemorating the 50th anniversary of Alan Shepard’s historic spaceflight, NASA Administrator Charlie Bolden said in a statement today that “we are still driven to reach for new heights in human exploration” and “we are just getting started.”

Calling May 5, 1961 “a good day,” Bolden noted that he was a teenager at the time and while “I never dared dream it growing up in segregated South Carolina, I was proud to follow in Alan’s footsteps several years later and become a test pilot myself.”

The statement went on to extol the Obama Administration’s policy of using NASA to facilitate the development of commercial crew for access to low Earth orbit, “allowing NASA to focus on those bigger, more challenging destinations and to enable our science missions to peer farther and farther beyond our solar system.”

NASA announced today its selection of three planetary mission candidates as part of its Discovery program, as well as three planetary exploration-related technology development projects.

Next year, one of the three mission candidates will be selected for a 2016 launch. In the meantime, each project team will receive $3 million to conduct the concept phase or preliminary design studies and analyses. The three, which were chosen from 28 submissions, are the following:

• Geophysical Monitoring Station (GES) to study the interior of Mars (Bruce Banerdt, JPL, principal investigator; JPL would manage the project),
• Titan Mare Explorer (TiME) to land in and float on a methane-ethane sea on Saturn’s Moon Titan (Ellen Stofan, Proxemy Research, principal investigator; Johns Hopkins University’s Applied Physics Lab would manage the project), and
• Comet Hopper to land on a comet multiple times and observe its changes as it interacts with the Sun (Jessica Sunshine, University of Maryland, principal investigator; NASA’s Goddard Space Flight Center would manage the project)

Discovery missions are cost-capped at $425 million not including launch costs. Eleven spacecraft in the Discovery series have been launched so far, including the MESSENGER spacecraft that recently entered orbit around Mercury.

NASA also selected three technology development proposals. Each team will receive an amount of money yet to be negotiated to bring the technologies to a higher level of readiness. The three that were selected are the following:

• Primitive Material Explorer (PME) to develop a mass spectrometer that can provide highly precise measurements of the chemical composition of a comet and the role of comets in delivering volatiles to Earth (Anita Cochran, University of Texas at Austin, principal investigator),
• Whipple: Reaching into the Outer Solar System to develop and validate a technique called blind occultation that could lead to discovery of various celestial objects in the outer solar system (Charles Alcock, Smithsonian Astrophysical Observatory, Cambridge, MA, principal investigator), and
• NEOCam to develop a telescope to study the origin and evolution of Near Earth Objects (NEOs) — comets and asteroids — and study the present risk of Earth impact (Amy Mainzer, JPL, principal investigator)

Fifty years ago tomorrow, May 5, Alan Shepard became the first American to reach space. Although his 15 minute flight was only suborbital, not orbital like Soviet cosmonaut Yuri Gagarin’s on April 12, it gave President John F. Kennedy enough confidence to announce just three weeks later the goal of landing a man on the Moon and returning him safely to Earth by the end of the decade.

Shepard launched from Cape Canaveral Air Force Station (CCAFS), FL in a Mercury capsule atop a Redstone rocket. The event is being commemorated tomorrow at CCAFS, adjacent to NASA’s Kennedy Space Center, at 9:00 am EDT and will be covered live on NASA TV. Shepard died in 1998. He was one of the original seven astronauts selected in 1959. Scott Carpenter, another member of that group, will be at the event tomorrow. It includes a recreation of the flight and recovery, and a tribute to Shepard’s second spaceflight, Apollo 14. (Shepard was grounded for most of the 1960s because of an inner ear disorder.)

The U.S. Postal Service released a stamp honoring Shepard’s flight earlier today.

NASA is now targeting May 10 as the earliest launch date for space shuttle Endeavour. NASA calls it a “success oriented” date that is subject to change as technicians continue to assess what it will take to repair a malfunctioning Load Control Assembly in the orbiter’s aft compartment.