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OTV-1

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Template:Infobox spacecraft USA-212[1][2] was the first flight of the Boeing X-37B Orbital Test Vehicle 1 (X-37B OTV-1), an American unmanned robotic spacecraft. It was launched aboard an Atlas V rocket from Cape Canaveral on 22 April 2010, and operated in low Earth orbit. Its designation is part of the USA series.

The spacecraft is operated by the United States Air Force, which has not revealed what the spaceship's specific payload is. The Air Force has stated only that the spacecraft will "demonstrate various experiments and allow satellite sensors, subsystems, components, and associated technology to be transported into space and back."[3]

Launch

USA-212 was launched on an Atlas V 501 rocket, tail number AV-012, from Space Launch Complex 41 at the Cape Canaveral Air Force Station in Florida.[4][5] The launch, which was conducted by United Launch Alliance, occurred at 23:52 UTC on April 22, 2010, placing the spacecraft into low Earth orbit for testing.[6]

The X-37B spacecraft was originally intended to be deployed from the payload bay of a NASA Space Shuttle, but following the Columbia accident, it was transferred to a Delta II 7920. It was subsequently transferred to the Atlas V following concerns over the X-37B's aerodynamic properties during launch.[7]

The launch was the first flight of the Atlas V 501 configuration,[8] and the first in four years to use a 5.4-meter (18 ft) payload fairing.[8][9] Prior to the installation of the spacecraft, the Atlas rocket was moved to the launch pad and performed a wet dress rehearsal on 2 April 2010.[10] It was returned to the Vertical Integration Facility the next day for final assembly.[11] The X-37 arrived at the VIF on 8 April. On 9 April, a 24-hour delay was announced. It subsequently slipped a further 24 hours after the landing of Space Shuttle Discovery on Mission STS-131 was delayed, as the Eastern Range could not have been reconfigured quickly enough to accommodate both events on the same day.[11] After a series of delays, it was set for 19 April 2010. On 21 April, the Atlas was rolled back out to the launch pad for launch.[11] The launch window on 22 April opened at 23:52 UTC, and closed at 00:01 on 23 April.

Mission

File:X-37B in Orbit.jpg
X-37 in orbit with deployed solar panel and open payload bay housing a telescope (artist's impression)

Most of the mission parameters for the USA-212 flight have not been disclosed.[5] The vehicle is capable of being on-orbit for up to 270 days. The Air Force stated the mission time will depend on progress of the craft's experiments during orbit.[12] Mission control is handled by the 3d Space Experimentation Squadron, 21st Space Wing, of the Air Force Space Command in Colorado Springs.[13]

Observations by amateur skywatchers

In May 2010, an amateur astronomer claimed to spot the spacecraft from his home in Toronto, Canada.[14] Shortly after the initial observation, several more detailed observations were made by amateur skywatchers from around the world, who reported the spacecraft to have an almost circular 401 to 422 km (249 to 262 mi) low Earth orbit with an inclination of 40°.[15] The group believed in their calculations and observations with a high degree of confidence.[15] The spacecraft's ground path was observed to repeat every four days, which was considered indicative for a possible imaging reconnaissance mission profile.[15][16]

For two weeks, starting on July 29, the amateur skywatchers were unable to find the spacecraft in the locations they had predicted, leading them to believe it had suddently changed its course.[17] During the mission, the vehicle was observed to change its orbit multiple times, with a total delta-v of the first four orbit changes amounting to 102 m/s (330 ft/s). A common characteristic of all the orbits was that the ground track nearly repeated every few days.[18][19] By November 12, 2010, the orbit had been lowered to 281 by 292 km (175 by 181 mi) with the ground track now repeating every 3 days (47 orbits).[18]

Altitude and ground track resonance history

Time period Periapsis
(AMSL) 		Apoapsis
(AMSL) 		Resonance
(orbits:days)
2010 Apr 22 – Aug 09[20] 403 km (250 mi)[20] 420 km (260 mi)[20] 61:4
2010 Aug 09 – Oct 06 433 km (269 mi)[20] 444 km (276 mi)[20] 91:6
2010 Oct 06 – Nov 01 390 km (240 mi) 395 km (245 mi) 46:3
2010 Nov 01 – Nov 12 315 km (196 mi) 328 km (204 mi) 31:2
2010 Nov 12 – Dec 3 281 km (175 mi) 292 km (181 mi) 47:3
Data collected by amateur observers and posted on the Seesat-l mailing list.[18]

Landing

Infrared view of OTV1 after landing

After completing its mission, the X-37B was deorbited, reentered the atmosphere, and landed at Vandenberg Air Force Base on 3 December 2010.[21] If unable to land at Vandenberg, Edwards Air Force Base was available as a backup site.[22] Range safety tracked the entire approach and landing sequence, and was ready to command a destruct of the vehicle if any serious problems occurred.[13]

The X-37B is the second reusable spacecraft to perform an automated landing after returning from orbit, the first being the Soviet Buran spacecraft in 1988.[23]

Hypothetical mission components

As the mission of USA-212 and the X-37B program are classified, public commentary on the program is speculation. James Oberg speculated that the concurrent launch of Air Force's Hypersonic Technology Vehicle HTV-2 was related to the mission. Part of an X-37B's mission profile might involve a simulated enemy attack, which the X-37B should be able to detect and autonomously counteract.[24] HTV-2 was launched at 23:00 UTC on April 22, 2010, i.e., 52 min ahead of X-37B, from Vandenberg Air Force Base in California,[25] yet got destroyed 9 minutes after launch.[26][27]


William Scott, coauthor of the techno-novel Counterspace: The Next Hours of World War III and former Rocky Mountain Bureau Chief for Aviation Week & Space Technology magazine believes that with X-37B, the Air Force might test weapon delivery from a space plane in low Earth orbit. He mentions Rods from God as a possible scenario.[28] This hypothesis aligns with speculation that the launch of USA-212 marks the beginning of military operations in space.[29]

See also

References

  1. ^ McDowell, Jonathan. "Issue 627". Jonathan's Space Report. Retrieved 23 April 2010.
  2. ^ "Secretive U.S. military space plane mission launched". Satellite News Digest. 23 April 2010. Retrieved 28 April 2010.
  3. ^ Lubold, Gordon (April 20, 2010). "Air Force To Launch X-37 Space Plane: Precursor To War In Orbit?". Christian Science Monitor. Retrieved 23 April 2010.
  4. ^ Leonard, David (22 October 2009). "Air Force's Secretive Space Plane Nears Maiden Voyage". Space.com.
  5. ^ a b Clark, Stephen (25 February 2010). "Air Force X-37B spaceplane arrives in Florida for launch". Spaceflight Now. Retrieved 3 March 2010.
  6. ^ Clark, Stephen (22 April 2010). "Atlas rocket delivers Air Force spaceplane to orbit". Spaceflight Now. Retrieved 23 April 2010.
  7. ^ Krebs, Gunter. "X-37B". Gunter's Space Page. Retrieved 2008-08-05.
  8. ^ a b "Air Force officials launch Atlas V carrying X-37B Orbital Test Vehicle". US Air Force. 2010-04-23. Retrieved 2010-04-23.
  9. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 23 April 2010.
  10. ^ Clark, Stephen (2 April 2010). "Air Force spaceplane is an odd bird with a twisted past". Spaceflight Now. Retrieved 23 April 2010.
  11. ^ a b c Ray, Justin (23 April 2010). "Mission Status Center". Atlas Launch Report. Spaceflight Now. Retrieved 23 April 2010.
  12. ^ Klotz, Irene. "U.S. Air Force X-37B Launched". Aviation Week and Space Technology, 24 April 2010.
  13. ^ a b "Air Force Bloggers Roundtable: Air Force set to launch first X-37B Orbital Test Vehicle". Department of Defense. 20 April 2010. Retrieved 23 April 2010.
  14. ^ "Amateur astronomers unravel X37-B orbit, say likely use for deploying spy satellites".
  15. ^ a b c Leonard David (22 May, 2010). "Secret X-37B spaceplane spotted by amateur skywatchers". Space.com. {{cite web}}: Check date values in: |date= (help)
  16. ^ William J. Broad (21 May 2010). "Surveillance Is Suspected as Spacecraft's Main Role". New York by. Retrieved 23 May 2010.
  17. ^ Peter Farquhar (August 25, 2010). "US military's top secret X-37B shuttle 'disappears' for two weeks, changes orbit". news.com.au.
  18. ^ a b c Molczan, Ted (2010-11-25). "Updated X-37B OTV 1-1 elements". http://www.satobs.org/seesat. Retrieved 2010-11-25. {{cite web}}: External link in |publisher= (help)
  19. ^ US military's top secret X-37B shuttle 'disappears' for two weeks, changes orbit.
  20. ^ a b c d e David, Leonard (2010-08). "Secret X-37B space plane has changed orbit". http://www.msnbc.msn.com. Retrieved 2010-12-05. {{cite web}}: Check date values in: |date= (help); External link in |publisher= (help)
  21. ^ Clark, Stephen. "Home again: U.S. military space plane returns to Earth". Spaceflight Now, December 3, 2010.
  22. ^ Covault, Craig (3 August 2008). "USAF To Launch First Spaceplane Demonstrator". Aviation Week and Space Technology.
  23. ^ Chertok, Boris (2005). Asif A. Siddiqi (ed.). Raketi i lyudi[[Category:Articles containing Russian-language text]] (trans. "Rockets and People") (PDF). NASA History Series. p. 179. Retrieved 2006-07-03. {{cite book}}: URL–wikilink conflict (help)
  24. ^ James Oberg (April 2010-04). "U.S. Air Force Launches Secret Flying Twinkie: Military's new space plane tests unnamed powers". IEEE Spectrum. Retrieved 2010-04-25. {{cite web}}: Check date values in: |date= (help)
  25. ^ Stephen Clark (April 2010-04-23). "New Minotaur rocket launches on suborbital flight". Spaceflight Now. Retrieved 2010-04-25. {{cite web}}: Check date values in: |date= (help)
  26. ^ "Falcon HTV-2 Launch Tests Hypersonic Vehicle Flight Capabilities" (PDF). DARPA. 2010-04-23. Retrieved 2010-12-05.
  27. ^ "DARPA Concludes Review of Falcon HTV-2 Flight Anomaly" (PDF). DARPA. 2010-11-16. Retrieved 2010-12-05.
  28. ^ Air Force's Mystery X-37B Space Plane Fuels Speculation
  29. ^ "CNN.com Video". CNN.
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