“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 s*x worker (C) stages a performance to denounce what they say is abuse and social stigma against them in Madrid, Spain, October 14, 2015. Placard reads "Prostitutes are the ones that make the streets dirty". (Photo by Andrea Comas/Reuters)

In this Wednesday, March 18, 2015 photo, limestone quarry workers walk through a cloud of dust spewed into the air by rotor blades of the stone-cutting machinery in the desert of Minya, southern Egypt. Around 45,000 people, including children, work in an estimated 1,500 quarries, digging out stones that later will be used in construction or powdered to be used by pharmaceutical and ceramic companies. (Photo by Mosa'ab Elshamy/AP Photo)

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)

“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)

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)

Palestinian boy Mohamad al-Sheikh, 12, who is nicknamed “Spiderman” and hopes to break the Guinness world records with his bizarre feats of contortion, demonstrates acrobatics skills on a beach in Gaza City June 2, 2016. (Photo by Mohammed Salem/Reuters)

A woman stands in a gift shop in central Rason city, part of the special economic zone northeast of Pyongyang, in this August 30, 2011 file photo. North Korea is a militarized, male-dominated society, but it is women who are making the money as the insular nation allows an unofficial market-based economy to take shape. (Photo by Carlos Barria/Reuters)