“A small British company with a dream of building a re-usable space plane has won an important endorsement from the European Space Agency (ESA) after completing key tests on its novel engine technology. Reaction Engines Ltd believes its Sabre engine, which would operate like a jet engine in the atmosphere and a rocket in space, could displace rockets for space access and transform air travel by bringing any destination on Earth to no more than four hours away”. – Chris Wickham via Reuters. Photo: Artist's impression of Skylon. (Photo by Reaction Engines Ltd)

A group of youngsters dressed as ghouls and zombies for Halloween parade in downtown Lisbon, Portugal, Friday, October 31, 2014. (Photo by Francisco Seco/AP Photo)

Russian President Vladimir Putin, center, uses a binocular, as Defense Minister Sergei Shoigu, left, and chief of Russia's military's General Staff Valery Gerasimov, right, observe military exercises near the Baikal Lake on Wednesday, July 17, 2013. (Photo by Alexei Nikolsky/AP Photo/RIA Novosti/Presidential Press Service)

“SpaceShipOne was a suborbital air-launched spaceplane that completed the first manned private spaceflight in 2004. That same year, it won the US$10 million Ansari X Prize and was immediately retired from active service. Its mothership was named “White Knight”. Both craft were developed and flown by Mojave Aerospace Ventures, which was a joint venture between Paul Allen and Scaled Composites, Burt Rutan's aviation company. Allen provided the funding of approximately US$25 million”. – Wikipedia

Photo: A chase plane follows SpaceShipOne after it reached a height of 62 miles in the first non-governmental flight to leave the Earth's atmosphere on June 21, 2004 in Mojave, California. SpaceShipOne spacecraft was carried to a height of 50,000 by the twin-turbojet high-altitude research aircraft, “White Knight”, where it was launched for its final climb. The space effort was funded by Microsoft co-founder Paul Allen and headed by aerospace engineer Burt Rutan. (Photo by Jim Campbell-Pool/Getty Images)

A dog groomer prepares a model dog during the 2nd Annual Shenzhen International Pet Exhibition, July 14, 2016, in Shenzhen, China. The pet exhibition runs from July 14 - 17, 2016 at the Shenzhen Convention & Exhibition Center. (Photo by VCG/Getty Images)

An invalis asking alms walks past a girl posing for the picture in the center of Ukrainian capital of Kiev on August 17, 2016. (Photo by Sergei Supinsky/AFP Photo)

A Iranian man walks with a sheep he bought at a market in the capital Tehran on September 12, 2016, as Muslims mark the first day of the Eid al-Adha (Feast of the Sacrifice) holiday. Muslims across the world celebrate the annual festival of Eid al-Adha, or the festival of sacrifice, which marks the end of the Hajj pilgrimage to Mecca and commemorates prophet Abraham's readiness to sacrifice his son to show obedience to God. (Photo by AFP Photo/Stringer)

Students from CAS Ballet Theatre School stretch on the sidewalk Saturday, February 20, 2016, in Ann Arbor, Mich. (Photo by Junfu Han/The Ann Arbor News via AP Photo)