After being forced to retreat from its operational area in late March 1945, Battery 836 was to have moved first to a location 16 km west of Osnabruck for firing operations, but the situation on the ground prevented this. They then moved to Celle (about 30 km north of Hanover). From there the remaining rockets were to be fired against Russian forces at Kostrzyn, 100 km northeast of Berlin. The unit could not set up in time to accomplish this before Kammler ordered the rocket units to be dissolved and convert to infantry. On April 8 the battery destroyed its rockets and launching equipment and ceased to exist. In all, 1593 V-2's had been fired against Antwerp, 1225 against London, and 461 against other cities and targets, by one accounting. A total of 3000 to 3280 missiles had been fired in combat launches, and another 440 to 1000 in test and training launches. A total of 6,100 missiles had been manufactured, at least 1,800 of which were early production versions that were either scrapped or cannibalised for later production.

The Air Research and Development Command informed the National Advisory Committee for Aeronautics that it had initiated a 30 day effort at the ballistic missile division to prepare a detailed development plan for "an extended manned space vehicle program of which man in space at the earliest practicable date is an integral part." The advisory committee was invited to participate in the preparation of the plan and to advise the Air Force of their anticipated action. (Msg, 04-9-01, Cmdr, ARDC, to Cmdr AFBMD, 9 Apr 58.)

A Thor/Able reentry test vehicle launched from Cape Canaveral, Florida, completed a successful flight down the Atlantic Missile Range. The reentry body of the Thor/Able was recovered at the far end of the range in the South Atlantic. This was the first recovery of an ablative nose cone following an ICBM-range flight.

The first Gemini mission, Gemini-Titan I, was launched from Complex 19 at Cape Kennedy at 11:00 a.m., e.s.t. This was an unmanned flight, using the first production Gemini spacecraft and a modified Titan II Gemini launch vehicle (GLV). The mission's primary purpose was to verify the structural integrity of the GLV and spacecraft, as well as to demonstrate the GLV's ability to place the spacecraft into a prescribed earth orbit. Mission plans did not include separation of the spacecraft from the second stage of the vehicle, and both were inserted into orbit as a unit six minutes after launch. The planned mission encompassed only the first three orbits and ended about four hours and 50 minutes after liftoff. No recovery was planned for this mission, but Goddard continued to track the spacecraft until it reentered the atmosphere on the 64th orbital pass over the southern Atlantic Ocean (April 12) and disintegrated. The flight qualified the GLV and its systems and the structure of the spacecraft.

Tyulin reveals that Voskhod 3 should be completely integrated and ready to go by the end of April, but the flight will be pushed back even farther than that. Mishin is also raising questions about Voskhod 4 and Voskhod 5. The cosmonauts are ready, but have nothing to do but wait. Who will supervise future manned space missions is in question. Korolev was de facto leader in the past. The others - the President of the State Commission, the President of the Academy of Sciences - were in fact just there in support roles. Without Korolev, this may change in the future, and the question has become controversial.

Deputy Administrator Robert C. Seamans, Jr., received a letter from John S. Foster, Jr., Director of Defense Research and Engineering, expressing pleasure that the agreement between the Department of Defense and NASA on extraterrestrial mapping, charting, and geodesy support had been consummated. He was returning a copy of the agreement for the NASA files.

Protoype Soyuz 7K-L1 manned circumlunar spacecraft. There are high winds for the L1 launch, 15-17 m/s. The official limit is 20 m/s, but Chelomei wants to scrub the launch if winds go over 15 m/s. Nevertheless the launch proceeds in 17-18 m/s winds and the L1 reached earth orbit. However the Block D translunar injection stage failed to fire (ullage rockets, which had to fire to settle propellants in tanks before main engine fired, were jettisoned prematurely). The failure is blamed on Mishin and has Tsybin seething in anger. Mishin is disorganised and has made many mistakes. Spacecraft burned up two days later when orbit decayed. Later in the day comes the news the RTS has to be replaced on one of the Soyuz 1/2 spacecraft. This will have a 3 to 4 day schedule impact, and push the launch back to 15-20 April. The crews arrive the same day for the upcoming Soyuz launch.

A Long Tank Thrust Augmented Thor/Agena D space booster lifted NASA's Nimbus 4 meteorological satellite into orbit from Vandenberg. This was the 400th launch.. of the Thor booster that was originally developed by the Air Force as an intermediate range ballistic missile (IRBM) in the 1950s. Environmental research. Primary experiments consisted of an image dissector camera system for providing daytime cloudcover pictures both in real-time and recorded modes, temperature-humidity infrared radiometer (THIR) for measuring daytime and nighttime surface and cloudtop temperatures as well as the water vapor content of the upper atmosphere, infrared interferometer spectrometer (IRIS) for measuring the emission spectra of the earth/atmosphere system, satellite infrared spectrometer (SIRS) for determining the vertical profiles of temperature and water vapor in the atmosphere, a monitor of ultraviolet solar energy (MUSE) for detecting solar UV radiation, a backscatter ultraviolet (BUV) detector for monitoring the vertical distribution and total amount of atmospheric ozone on a global scale, a filter wedge spectrometer (FWS) for accurate measurement of IR radiance as a function of wavelength from the earth/atmosphere system, a selective chopper radiometer (SCR) for determining the temperatures of six successive 10-km layers in the atmosphere from absorption measurements in the 15-micrometer CO2 band, and an interrogation, recording, and location system (IRLS) for locating, interrogating, recording, and retransmitting meteorological and geophysical data from remote collection stations. The spacecraft performed well until April 14, 1971, when attitude problems started. The experiments then operated on a limited time basis until September 30, 1980.

Provision of uninterrupted round the clock telephone and telegraph radiocommunication in the USSR and simultaneous transmission of colour and black-and-white USSR central television programmes to stations in the Orbita network. Positioned in geosynchronous orbit at 85 deg E in 1983-1984 As of 4 September 2001 located at 65.56 deg E drifting at 0.028 deg W per day. As of 2007 Mar 10 located at 82.54E drifting at 0.059W degrees per day.

Prototype of DFH-2 communications satellite. After on-orbit testing and check out of the satellite and the ground stations, the satellite system was declared operational, and was used experimentally for the transmission of television, telephone, and data messages with good results. It stayed in operation for more than four years, exceeding the design life of three years by a comfortable margin. Operated in geosynchronous orbit at 125 deg E in 1984-1988. As of 4 September 2001 located at 40.81 deg E drifting at 0.320 deg W per day. As of 2007 Feb 27 located at 133.57E drifting at 0.079W degrees per day.

Manned five crew. Carried Atlas-2; deployed and retrieved Spartan 201. Payloads: Atmospheric Laboratory for Applications and Science (ATLAS) 2, Shuttle Solar Backscat-ter Ultraviolet (SSBUV) A, Shuttle Pointed Autonomous Research Tool for Astronomy (SPARTAN) 201 (Solar Wind Generation Experi-ment), Solar Ultraviolet Experiment (SUVE), Commercial Material Dispersion Apparatus (CMIX), Physiological and Anatomical Rodent Experiment (PARE), Hand-held, Earth-oriented, Real-time, Cooperative, User-friendly, Location-targeting, and Environmental System (HER-CULES), Shuttle Amateur Radio Experiment (SAREX) II, Space Tissue Loss (STL), Air Force Maui Optical Site (AMOS), Cosmic Radiation Effects and Activation Monitor (CREAM), Radiation Monitoring Equipment (RME) III.

Spartan Flight Support Structure was an MPESS class cross-bay truss structure on which Spartan 204 was mounted. The Spartan satellites were small free flyers deployed by the RMS robot arm for a couple of days and then retrieved. SPTN-204 carried NRL's FUVIS Far Ultraviolet Imaging Spectrograph which was used to study the Shuttle environment and make astronomical observations. This was the first Spartan mission to be sponsored by the USAF Space Test Program rather than NASA.

Launch delayed from March 22, April 4. Space Shuttle Atlantis entered an orbit of approximately 59 x 229 km x 51.6 deg at 2052 UTC, and separated from the External Tank, ET-114. ET-114 reached apogee around 2122 UTC and reentered over the Pacific about 2150 UTC at the end of its first orbit. Atlantis fired its OMS engines at apogee to raise its perigee to 155 km. Further orbit changes will lead to a rendezvous with the Space Station on Station mission 8A. STS-110 carried the S0 truss segment to the Station. The truss was the first segment of the main backbone of the Station which was to grow to carry the large solar panel wings and radiators. Cargo manifest:

• Bay 1-2: Orbiter Docking System - 1800 kg + 3 EMU spacesuits - 360 kg
• Bay 4-13: S0 Truss - 12623 kg. The S0 truss, built by Boeing/Huntington Beach, was 13.4 m long and 4.6 m in diameter. The main truss had a hexagonal cross section. One face carried fluid, power and data cables, while another face carried the rails for the Mobile Transporter. The S0 contained avionics, GPS antennae, and a radiation dose monitor. The S0 would be attached to the LCA (Lab Cradle Assembly) which was attached to the top of the Destiny lab module in 2001. Attached to S0 were:
  • 4 x MTS (Module to Truss Structure) struts. These were used to connect it to the Destiny module
  • Airlock Spur. This was a 4.2 m beam that hinged out to connect to the Quest module and had handrails for spacewalkers
  • Mobile Transporter (MT). This was made by TRW Astro Aerospace in Carpinteria and was an 885 kg, 2.7 m long truck which moved on the S0 rails to transfer heavy cargo along the truss.
• Sill: RMS arm - 410 kg
• Total: 15193 kg

The Quest airlock was depressurized at 1236 GMT. Cosmonaut Budarin supported the operations from inside the station. One of the more important tasks was to reroute power cables for two of the station's critical control moment gyros, so that the pair could not be disabled by any single power disruption. This was important to provide extra redundancy, since one of the four total gyros has already failed and could not be replaced due to the grounding of the shuttle fleet after the STS-107 disaster.

White Knight/SpaceShipOne Flight 53L / 13P. 40 second motor burn time. Handling qualities during boost, through transonic and supersonic. Reaction control system functionality in-flight and feather configuration stability during transonic re-entry. Evaluation of radar tracking capability. Launch conditions were 13.96 km and 230 kph. A planned immediate motor ignition was delayed about 2 minutes to evaluate a shock induced stall buffet resulting in an ignition altitude of only 11.7 km. The 40 second rocket boost was smooth with good control. Pilot commented that the motor was surprisingly quiet; however the boost was heard by ground observers. Burnout occurred at 1.6M and apogee was over 32 km. There was no noted flight control flutter or buzz during the climb. Feather recovery was nominal. Maximum feathered speed on entry was 0.9 Mach. The wing was de-feathered and locked by 12 km. Handling quality assessments during descent were satisfactory and a smooth landing made to runway 30 at Mojave. All video and tracking systems performed well with spectacular footage obtained onboard, from chase and from ground stations.

Launched the EO-17 long-duration crew to replace the EO-16 crew. The commander was the son of cosmonaut Aleksandr Volkov. Also aboard was Oleg Kononenko (no relation to the 1970's Buran pilot of the same name) and Korean astronaut Yi Soyeon. Soyuz TMA-12 docked at the Pirs module of the International Space Station on 2008 Apr 10 at 12:57 GMT on 10 April. Volkov and Kononenko stayed aboard as the EO-17 long duration crew. Yi returned to earth with the EO-16 crew aboard Soyuz TMA-11. Soyuz TMA-12 undocked on 24 October at 00:16 GMT with the EO-17 crew of Kononenko and Volkov, plus space tourist Richard Garriott, aboard. They landed safely at 03:37 GMT.

Falcon 9 F9-023 launched a Dragon with the Bigelow BEAM inflatable module experiment in its trunk. CRS-8 was scheduled to arrive at ISS on Apr 10. The F9-023 first stage performed boostback and reentry burns to successfully land on the ship "Of Course I Still Love You" at 78.50W 30.50N in the Atlantic. This was the second succesful reentry and landing of a Falcon 9 first stage, following the Dec 2015 landing of F9-021 at Cape Canaveral. Dragon CRS-8 arrived at the capture point 10m from the Harmony module at 1115 UTC Apr 10. The Canadarm-2 grappled it at 1123 UTC and berthed it on Harmony's nadir CBM port at 1357 UTC. At about 0600 UTC on Apr 16 the BEAM module was extracted from Dragon's trunk; BEAM was installed on the Tranquility module's aft port at 0937 UTC Apr 16. CRS-8 was unberthed at 1102 UTC May 11 and released into space at 1319 UTC. After a deorbit burn at 1801 UTC it splashed down around 120.1W 31.4N, off the coast of California, at 1851 UTC. The CRS-8 Dragon brought back to Earth the EMU 3011 spacesuit implicated in the Parmitano and Kopra water leaks. EMU 3011 was launched into space on mission STS-132 in 2010. Also brought back aboard CRS-8 were the Flock-2b 11 and 12 cubesats which failed to deploy from the ISS last October. Nanoracks deployers NRCSD-5 and NRCSD-6 were also returned to Earth on CRS-8. The Bigelow Expansion Activity Module (BEAM) remains attached to Node 3. On May 28 the module expansion was successfuly carried out; the process of expanding and pressurizing the module took from 1305 to 2044 UTC. The diameter of the module was 3.2metres; its length was increased by 1.8m to about 3.7m.