“The Lockheed Martin X-33 is an unmanned, sub-scale technology demonstrator suborbital spaceplane developed in the 1990s under the U.S. government-funded Space Launch Initiative program”. – Wikipedia

Photo: An Artist's Rendering Shows How Nasa's X-33 Technology Demonstrator, A Cost-Cutting Fully Reusable Single-Stage-To-Orbit Space Vehicle, Will Look Upon Completion. The 67 Foot-Long, 278,600 Pound, Twin Engine Space Vehicle, Capable Of Reaching Speeds In Excess Of Mach 15, Will Lead To The Construction Of A 127 Foot-Long, 2,186,000 Pound Version With Seven Engines And A 50,000 Pound Payload Capacity Called The “Venturestar”. (Photo By Nasa/Getty Images)

A retired man (L) looks toward two girls wearing miniskirts, July 13, 1969 in Nice, France. (Photo by AFP Photo)

Model Jill de Jong from the Netherlands poses for photographers August 29, 2002 at Earls Court in London. (Photo by Scott Barbour/Getty Images)

Bolivia's president Evo Morales holds his scared staffs of power during a blessing by Aymaran spiritual guides, in a traditional ceremony at the archeological site Tiwanaku, Bolivia, Wednesday, January 21, 2015. Morales is set to begin a new term Thursday, that will make him the Andean nation's longest-serving leader, riding high on a wave of unprecedented growth and stability. (Photo by Juan Karita/AP Photo)

An x-ray of a woman drinking, taken by British artist and photographer Hugh Turvey in London, England. (Photo by Hugh Turvey/SPL/Barcroft Media)

Physicist Arie van't Riet uses a series of duel X-ray cameras to capture flowers, plants and small animals in living dioramas. The x-rays are then finished and colorized in Photoshop. Giving way to some breathtaking nature scenes. Photo: “Chameleon and Begonia”. (Photo by Arie van't Riet)

Models promote a condom brand at the first Shenzhen s*x Culture Festival on September 21, 2007 in Shenzhen of Guangdong Province, China. The festival aims to increase awareness about reproductive health and popularise s*x education. (Photo by China Photos/Getty Images)

“The Boeing X-45 unmanned combat air vehicle is a concept demonstrator for a next generation of completely autonomous military aircraft, developed by Boeing's Phantom Works. Manufactured by Boeing Integrated Defense Systems, the X-45 was a part of DARPA's J-UCAS project”. – Wikipedia

Photo: Two X-45A Unmanned Combat Air Vehicles (UCAV) are shown to members of the news media July 11, 2002 at Edwards Air Force Base, California. The X-45A, developed by The Defense Advanced Research Projects Agency and the Boeing Company, is the first unmanned system designed from inception for combat missions. (Photo by David McNew/Getty Images)