place and secrets have gone hand in deal since the start of aeronautics . After all , the space subspecies occurred at the height of the Cold War . The geopolitical site might have changed but nations still get off private missions into space .
The ironically better - know one is the US Air Force Space Plane , or X-37B , presently in its fifth cryptic foreign mission in orbit . The uncrewed vehicle , also known as the Orbital Test Vehicle ( OTV ) , has now pass more than 400 days in range , testing newfangled technical school and potentially deploy small planet .
While an telling mean solar day count , the mission is currently second to last for duration . OTV-1 , which launched in 2010 , was the first and shortest mission at 224 days . Every missionary work since then has go the continuance of its predecessor . OTV-4 last 717 days and 20 hours , less than two weeks from a full two year in space . As OTV-5 go when X-37B was plunge onSeptember 7 , 2017 , to ticktock the previous phonograph record it will have to come back down sometime after August 25 , 2019 .
X-37B was originally a NASA project and it owes a lot of its design to the Space Shuttle orbiter , which were used in 135 missions from 1981 to 2011 . The space aeroplane itself see like a smaller version of the iconic crew launcher . Just like the Space Shuttle , it has a cargo bay with a robotic weapon system , although the hold is roughly as magnanimous as a truck . It is only 8.8 metre ( 29 feet ) in length with a wingspread of 4.6 measure ( nearly 15 feet ) . It is solar powered and weighs approximately 5 tonnes ( 5.5 ton ) .
“ The X-37B Orbital Test Vehicle , or OTV , is an data-based test political program to demonstrate technologies for a reliable , recyclable , unmanned place test platform for the US Air Force , " explains the officialAir Force web site .
" The primary object of the X-37B are dual : recyclable spacecraft engineering for America ’s futurity in blank space and operating experiments which can be fall to , and examined , on Earth . ”
Most of the payload of X-37B is nameless ( add up on , it ’s a secret outer space plane after all ! ) but it has been annunciate that it ’s try out the Advanced Structurally Embedded Thermal Spreader II , which measures the performance of an oscillating oestrus pipe , as well as carry several small satellites .
