Space Shuttle Discovery is towed from the shuttle landing facility to the orbiter processing facility at Kennedy Space Center on April 20, 2010 in Cape Canaveral, Florida. Discovery's landing attempts at KSC were scrubbed yesterday due to unacceptable weather conditions. Discovery is returning from a successful mission to the International Space Station. (Photo by Matt Stroshane/Getty Images). CAPE CANAVERAL, FL – APRIL 20 2010

Supermodel Iman (center) introduces her husband David Bowie (L) to Rihanna (R) at the DKMS' 5th Annual Gala: Linked Against Leukemia honoring Rihanna & Michael Clinton hosted by Katharina Harf at Cipriani Wall Street on April 28, 2011 in New York City. (Photo by Andrew H. Walker/Getty Images for DKMS)

In this handout photo provided by the Helmholtz Center for Research on Infectious Diseases an EHEC bacteria is visible on May 30, 2011 in Berlin, Germany. German health authorities have attributed at least 14 deaths within the last two weeks to an outbreak of enterohemorrhagic E. coli, also known as the EHEC bacteria. (Photo Courtesay Manfred Rohde, Helmholtz-Zentrum fuer Infektionsforschung (HZI)/Getty Images)

Controlled fires lit by residents glow in the hills over the village of Pottenstein during the annual Epiphany celebration on January 6, 2012 in Pottenstein, Germany. The ceremony, which also includes a procession with torches through the village center, is part of a tradition going back to 1905. Pottenstein was once a pilgrimage destination. (Photo by Johannes Simon/Getty Images)

A model walks the runway at the Luca Luca Spring 2012 fashion show during Mercedes-Benz Fashion Week at The Stage at Lincoln Center on September 9, 2011 in New York City. (Photo by Frazer Harrison/Getty Images for Mercedes-Benz Fashion Week)

Model Amanda Kaspor of Highland, Michigan poses with the CT&T e-Zone Plus electric car is displayed during the press preview for the world automotive media North American International Auto Show at the Cobo Center January 12, 2010 in Detroit, Michigan. (Photo by Bryan Mitchell/Getty Images)

Eight-year-old handicapped Chinese girl Qian Hongyan crawls with two home-made props and part of a basketball at Zhuangxia Village on January 5, 2005 in Luliang County of Qujing City, Yunnan Province, China. The girl who lost both of her legs in a traffic accident in 2000 at the age of three, struggles to live her life with a basketball as an underprop, “walking” between school and home by herself. The girl's story is widely reported in the country, and experts from China Rehabilitation Research Center has come to Qian's home to help her for rehabilitative treatment early 2005. (Photo by China Photos/Getty Images)

NASA space shuttle Atlantis is prepared on the Vehicle Assembly Building floor at the Kennedy Space Center May 18, 2011 in Cape Canaveral, Florida. The space shuttle program ends with Atlantis mission STS-135 scheduled for early July. Space shuttle Atlantis will carry the Raffaello multipurpose logistics module to deliver supplies, logistics and spare parts to the International Space Station. Atlantis also will fly a system to investigate the potential for robotically refueling existing spacecraft and return a failed ammonia pump module. (Photo by Roberto Gonzalez/Getty Images)