Editing Courier 1B

{{Infobox spaceflight
| name                = Courier 1B
| image               = Courier-1A.jpg
| image_caption       = Courier 1 satellite

| mission_type        = [[Communications satellite|Communications]]
| operator            = [[United States Army|US Army]] / [[DARPA|ARPA]]
| COSPAR_ID           = 1960-013A
| Harvard_designation = 1960 NU 1
| SATCAT              = 00058
| mission_duration    = 17 days (achieved) <br/> {{time interval|October 4, 1960, 17:45:00}} <br/> (in orbit)
| orbits_completed    = 1000

| spacecraft_bus      = 
| manufacturer        = Western Development Labs,<br/>division of [[Philco]]
| launch_mass         = 225 kg <ref name="Display"/>
| power               = 60 watts

| launch_date         = 4 October 1960, 17:45:00 GMT
| launch_rocket       = [[Thor-Ablestar|Thor-Able-Star]]
| launch_site         = [[Eastern Range|Cape Canaveral]], [[Cape Canaveral Space Launch Complex 17|LC-17B]]
| launch_contractor   = [[Douglas Aircraft Corporation|Douglas]] / [[Aerojet]]

| disposal_type       = 
| deactivated         = 
| last_contact        = 21 October 1960
| decay_date          =

| orbit_epoch         = 4 October 1960
| orbit_reference     = [[geocentric orbit|Geocentric]]<ref name="Trajectory"/>
| orbit_regime        = [[low Earth orbit|Low Earth]]
| orbit_periapsis     = 938 km
| orbit_apoapsis      = 1237 km
| orbit_inclination   = 28.33°
| orbit_period        = 106.8 minutes
| apsis               = gee
}}

[[File:1960-10-06 Florida.webm|thumb|right|thumbtime=3|Universal newsreel about the launch of Courier 1B]]

'''Courier 1B''', is the world's first active [[repeater]] communications satellite, Courier 1B was successfully launched on  October 4, 1960 at 17:45:00 [[Greenwich Mean Time|GMT]] from Cape Canaveral, Florida. The first Courier satellite in Project Courier, '''Courier 1A''', was lost 2.5 minutes after lift-off on August 18, 1960.

==History==
As a Cold War initiative, Courier 1B was the 26th satellite launched by the US as opposed to the Soviet Union's six satellites since Sputnik I in 1957. Proposed by the [[US Army Signal Corps]] in September 1958, Courier 1B was a follow-up to [[SCORE (satellite)|SCORE]] program launched December 18, 1958. SCORE "was the first step of an evolutionary program to develop communication satellite systems for use by the military services".<ref>T.P. Mottley, D.H. Marx, W.P. Teetsel, "A Delayed - Repeater Satellite Communication System of Advanced Design", ''IRE Transactions on Military Electronics'', Vol. MIL-4, No. 2, April–July 1960. p. 195.</ref> The '''Project Courier''' was a joint program of the US [[United States Department of Defense|Department of Defense]] [[DARPA|(ARPA)]] along with the US [[Signal Corps (United States Army)|Army Signal Research and Development Laboratory]] at [[Fort Monmouth]], [[New Jersey]].

Courier 1B would receive messages or photographs, store them, and then re-transmit them. Courier 1B was:

:''An experimental system to demonstrate the feasibility of using satellites for providing a solution to global communications problems. It was designed to store teletype messages and transmit them at high speed while the satellite is in view of a ground station... orbiting Earth at {{convert|1000|km}}''.<ref name=":0">Bartow, James E., Mottley, Thomas P., Teetsel, Walter P. "The Courier Communications System". In ''Telecommunication Satellites'', edited by K.W. Gatland (London: Illife Books LTD., 1964), p. 156.</ref>

==Spacecraft==
Courier 1B was built by the Western Development Labs (WDL) division of [[Philco]], previously known as "Army Fort Monmouth Laboratories". Philco was bought by [[Ford Motor Company]], becoming part of its [[Ford Aerospace]] division, which was acquired by [[Loral Corporation]]. WDL then became part of [[Space Systems/Loral]] division of [[Loral Space & Communications]]. IT&T provided ground support equipment and Radiation, Inc, Melbourne, Florida, made the large dish ground antennas. Sonotone Corporation, Elmsford, New York developed the on-board power system for the satellite.

Courier 1B was a {{convert|225|kg}}, {{convert|129.5|cm}} diameter sphere, {{convert|135|kg}} of this was the electronic equipment payload. It carried four 2-W microwave FM (1700-1800&nbsp;MHz) transmitters and a 50-mW transistorized VHF beacon transmitter subsystem. It contained four solid-state receivers in the 1800-1900&nbsp;MHz microwave band. Five tape recorders were used to store data for later playback. Four of these were digital with a total capacity of 13.2&nbsp;Mb (4 minutes at 55&nbsp;kbit/s) each. One was an analog recorder with a 4-minute capacity and a range of 300 to 50,000&nbsp;Hz.<ref name="Display"/>

Four [[whip antenna]]s were mounted at 90° intervals along the equator of the sphere. It also held two [[microwave antenna]]s, a transistorized telemetry generator, a VHF [[diplexer]], and a command decoder. The transmitters and receivers were set up so two of each would be running at any given time, the others were on standby and could be switched in by ground command. The sphere was covered with 19,200 solar cells, charging nickel-cadmium batteries, providing 60 W power. It was the first satellite to use nickel–cadmium storage batteries.<ref name="Display"/>

The satellite had the capability to simultaneously transmit, receive, and store approximately 68,000 coded words per minute. It also had real-time communications mode, supporting a single half-duplex voice circuit. The mission was operated by two monitoring stations in New Jersey and Puerto Rico using special 8.5 meters of dish antennas.<ref name="Display">{{Cite web |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1960-013A|title=Courier 1B: Display 1960-013A|date=27 February 2020|website=nssdc.gsfc.nasa.gov|publisher=NASA|access-date=28 April 2020}} {{PD-notice}}</ref>

==Mission==
Courier 1B launched on 4 October 1960 at 17:45:00 GMT from the [[Eastern Range|Atlantic Missile Range]] at [[Cape Canaveral]], [[Florida]]. The launch vehicle was a [[Thor-Ablestar|Thor-Able-Star]], comprising a modified USAF [[PGM-17 Thor|Thor IRBM]] first stage and a USAF Able-Star upper stage with a re-startable liquid engine. The satellite was successfully inserted into an orbit with a [[Apsis|perigee]] of {{convert|938|km}}, an [[Apsis|apogee]] of {{convert|1237|km}}, an [[Orbital inclination|inclination]] of 28.33°, and an [[Orbital period]] of 106.8 minutes.<ref name="Trajectory">{{Cite web |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/displayTrajectory.action?id=1960-013A|title=Courier 1B: Trajectory 1960-013A|date=27 February 2020|website=nssdc.gsfc.nasa.gov|publisher=NASA|access-date=29 April 2020}} {{PD-notice}}</ref> Messages were successfully received and transmitted and the satellite operated nominally until a command system failure ended communications 17 days after launch.<ref name="Display"/>

After completing a first orbit, a teletype message to the [[United Nations General Assembly]] from [[President of the United States]] [[Dwight D. Eisenhower]] was sent to [[United States Secretary of State]] [[Christian Herter]], to be delivered by Herter to [[Frederick Boland]], President of the General Assembly at the United Nations then in session at New York. The message of Eisenhower was transmitted by Courier 1B from the Camp Evans, [[Deal Test Site]], a New Jersey off-base transmission facility of [[Fort Monmouth]]. The message was relayed to the Camp Salinas Training Area, a ground station and tracking installation in [[Salinas, Puerto Rico|Salinas]], [[Puerto Rico]]. If Courier 1B was in sight of the two ground stations at the same time, Courier 1B had the capability of "real time" messaging.<ref>Bartow, Mottley, Teetsel. "The Courier Communications System". In ''Telecommunication Satellites'', p. 157.</ref>

Courier 1B had an effective message transmission rate of 55,000 bits per second and:

''Used ultra–high frequency (UHF) communications. This portion of the electromagnetic spectrum had remained relatively unused and generally free from man-made and atmospheric interference. The Courier satellite could simultaneously transmit and receive approximately 68,000 words per minute while moving through space at 16,000 miles per hour, and could send and receive facsimile photographs.<ref>{{Cite book|url=https://history.army.mil/html/books/030/30-17-1/CMH_Pub_30-17-1.pdf|title=Getting the Message Through A Branch History of the US Army Signal Corps|last=Raines|first=Rebecca Robbins|publisher=Center of Military History, US Army|year=1996|location=Washington, D.C.|pages=332|access-date=2018-05-30|archive-url=https://web.archive.org/web/20191026142001/https://history.army.mil/html/books/030/30-17-1/CMH_Pub_30-17-1.pdf|archive-date=2019-10-26|url-status=dead}}</ref>

After 228 orbits over 17 days, the payload failed to respond to commands. It was believed that the clock-based access codes got out of synchronization and the satellite would not respond to what it interpreted as unauthorized commands.

==See also==
{{Portal|Spaceflight}}
* [[List of communications satellite firsts]]

==References==
{{Reflist}}

==Further reading==
* James E. Bartow, Thomas P. Mottley, Walter P. Teetsel, "The Courier Communications Satellite System". In ''Telecommunication Satellites (Theory, Practice, Ground Stations, Satellites, Economics)'', edited by K.W. Gatland. pp. 156-183
* T.P. Mottley, D.H. Marx, W.P. Teetsel, "A Delayed-Repeater Satellite Communication System of Advanced Design". In ''IRE Transactions on Military Electronics'', Vol. MIL-4, No. 2, April–July 1960, pp. 195-207. N.B.: ''IRE Transactions on Military Electronics'' is currently published as ''IEEE Transactions on Aerospace and Electronic Systems''
* T. P. Mottley, W. P. Teetsel, P. W. Siglin, "Project Courier Final Report", AD224091, U. S. Army Signal Research and Development Laboratory, Fort Monmouth, New Jersey, July 24, 1961
* Pierce W. Siglin & George Senn, "Courier Communication Satellite". In ''The Journal of the Institution of Electrical Engineers'', Vol. 7, August 1961, pp. 504-508
* G.F. Senn & P.W. Siglin, "Courier Satellite Communication System". In ''IRE Transactions on Military Electronics'', Vol. MIL-4, No. 4, October 1960, pp. 407-413. N.B.: ''IRE Transactions on Military Electronics'' is currently published as ''IEEE Transactions on Aerospace and Electronic Systems''

==External links==
* [http://space.skyrocket.de/doc_sdat/courier.htm Information on Courier 1A and 1B at Gunter's Space Page]
* [https://web.archive.org/web/20120723165008/http://www.campevans.org/_CE/html/tac-bro66.html Courier 1B history at CampEvans.org (Home of InfoAge.]
* [http://smcheritagefoundation.org/courier-1b/ Courier Page of SMC Heritage Foundation]

{{Orbital launches in 1960}}

[[Category:Communications satellites in low Earth orbit]]
[[Category:Spacecraft launched in 1960]]