Mark Riccobono, executive director of the Jernigan Institute of the National Federation of the Blind speaks at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Mark Riccobono, executive director of the Jernigan Institute of the National Federation of the Blind, at podium, delivers remarks at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Chris Scolese, NASA Associate Administrator, speaks at a ceremony where senior NASA officials presented the National Federation of the Blind, with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Chris Scolese, NASA Associate Administrator, speaks at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Dr. Marc Mauer, president of the National Federation of the Blind, at podium, speaks at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Dr. Marc Mauer, president of the National Federation of the Blind speaks at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

House Majority Leader U.S. Rep. Steny Hoyer, D-Md., smiles as he speaks to those in attendance at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

House Majority Leader U.S. Rep. Steny Hoyer, D-Md., speaks at a ceremony where senior NASA officials presented the National Federation for the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA astronaut Greg Johnson, at podium, speaks at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

House Majority Leader U.S. Rep. Steny Hoyer, D-Md., speaks at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA astronaut Greg Johnson, left, speaks with Dr. Marc Mauer, president of the National Federation of the Blind, right, prior to a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

House Majority Leader U.S. Rep. Steny Hoyer, D-Md., speaks at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

House Majority Leader U.S. Rep. Steny Hoyer, D-Md., speaks at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Derrick Tuff, right in wheelchair, and Kayla Weathers, standing left, deliver remarks at a ceremony where senior NASA officials presented the National Federation of the Blind with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Man standing at center is unidentified. Photo Credit: (NASA/Paul E. Alers)

Dr. Marc Mauer, president of the National Federation of the Blind accepts an award from William Gerstenmaier, Associate Administrator, Space Operations, NASA Headquarters at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Mark Riccobono, executive director of the Jernigan Institute of the National Federation of the Blind, right, accepts an award from Dr. Joyce Winterton, Assistant Administrator, Office of Education, NASA Headquarters, center, and Ken Silberman, from Goddard Space Flight Center, at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

Dr. Marc Mauer, president of the National Federation of the Blind, left, accepts two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009 from NASA Associate Administrator Chris Scolese, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

NASA Associate Administrator Chris Scolese, left, and Mark Riccobono, executive director of the Jernigan Institute of the National Federation of the Blind hold up a Braille enscribed award with two Louis Braille Bicentennial Silver Dollars at a ceremony where senior NASA officials presented the NFB with coins that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

House Majority Leader U.S. Rep. Steny Hoyer, D-Md., left, holds up an award presented to him by Mark Riccobono, executive director of the Jernigan Institute of the National Federation of the Blind at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

NAME sings the National Anthem at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)

NAME sings the National Anthem at a ceremony where senior NASA officials presented the NFB with two Louis Braille Bicentennial Silver Dollars that flew on Space Shuttle Atlantis' mission (STS-125) to the Hubble Space Telescope in May 2009, Friday evening, July 31, 2009, at the Capitol Visitors Center in Washington. Photo Credit: (NASA/Paul E. Alers)