RS-19 was launched at 2322 hours EST from AMR. The flight was successful. The actual range was 169.4 nm; 13 nm over the intended impact point. Cut-off wee given by the alcohol depletion switch that sensed alcohol injector pressure drop-off. Takeoff occurred 0.156 seconds after firing. The missile followed the correct trajectory with no obvious deviation. Missile cut-off occurred later than predicted and caused the missile to impact approximately 6.5 nm long, During descent the warhead turned left, causing impact to be several miles to the left of the aiming azimuth line. The primary test objectives were to test the angle-of-attack meter hardware (Jupiter control). Missed aimpoint by 25,100 m.

First launches from Arensch to Berensch of DRG (German Rocket Society) 'postcard rockets'. 100 would be launched in the next two years. Ten launches were made carrying 5000 postcards. The subsonic 5 kg rockets were 2 m long, produced 50 kgf thrust, were recovered under three or four parachutes, and had an average accuracy of 130 m over a 3 km range.

After 22 orbits, virtually all spacecraft systems had failed, and Cooper manually fired the retrorockets and the spacecraft reentered the atmosphere, landing safely in the Pacific Ocean at 23:24 GMT, 34 hours, 19 minutes, and 49 seconds after liftoff. Cooper was reported in good condition, and this turned out to be the final Mercury flight.

Tyulin has already warned that military crews at Baikonur are 'going slow' in Voskhod 3 preparations. Now it is reported from Voronezh that the military quality control official is refusing to certify the engines for the third stage of Voskhod 3 as ready for flight. It is clear that the flight will slip into June at this rate...

The cosmonauts tour Leningrad, visiting the sites of the October Revolution - the Battleship Aurora, Winter Palace, etc. Except for Shatalov and Kamanin, none had ever been there before. They also visited subcontractor premises and military units involved in the space programme.

Keldysh first revealed the new 'party line' at a press conference on the semi-successful Venera 5 landing on Venus. When asked about Soviet lunar plans, he revealed that Russia would only use robot probes, that it wouldn't risk men's lives in such an endeavour. At the same time Babakin was hard at work finishing the first Ye-8-5 robot lunar soil return spacecraft, to be launched before Apollo 11.

First Rokot flight from Plesetsk, using a launch pad originally used for Kosmos rockets. The two-stage modified UR-100NUTTKh ICBM, delivered a Briz-KM upper stage to a suborbital trajectory. The first Briz burn was to an approximately 200 x 550 km transfer orbit; the second burn circularized at apogee. It placed two 660 kg dummy satellites in orbits similar to the parking orbit was used for the defunct Iridium program. The Briz-KM stage then made a third burn to lower its perigee to a 178 x 556 km x 86.4 deg disposal orbit.

Pablo de León (Buenos Aires, Argentina tested his vehicle's life support systems, pressure suit, and environment controls using several high altitude glider flights to 30,000 feet using their space suit system. The suit also underwent several thermal tests in a cold chamber (-35 Centigrade) and external temperatures were sustained for more than 2 hours.

Final space station assembly mission. Also delivered spare parts. Endeavour docked with the Station at 10:14 GMT on 18 May. The ELC-3 carrier was unberthed from the shuttle at 13:27 GMT and installed on the Station's truss at 16:09 GMT. The AMS-02 Alpha Magnetic Spectrometer was unberthed at 06:59 GMT on 19 May and bolted to the Station's S3 truss at 09:46 GMT. Cargo Bay Manifest:

• External Airlock/ODS: 1800 kg
• EMU spacesuits 3004, 3018: 260
• RMS arm 201: 410 kg
• Orbiter Boom Sensor System: 382 kg
• Alpha Magnetic Spectrometer (particle detector to search for antimatter): 6917
• STORRM (lidar to test rendezvous and docking technology for the Orion spacecraft): 17 kg
• PPSU-2 electronics box: 17 kg
• SPDU: 17 kg kg
• ROEU 755 umbilical for ELC-3: 90 kg
• ROEU 751 umbilical for AMS-02: 78 kg
• MISSE carriers (3): 171 kg
• MISSE 8 experiment (studies the effect of exposing various materials to space): 45 kg
• Express Logistics Carrier:
  • ELC-3 plus support hardware: 3207 kg
  • Cargo Transport Container: 476 kg
  • SASA-2R S-band antenna: 116 kg
  • SASA-3R S-band antenna: 116 kg
  • SPDM Arm 3/OCTM: 342 kg
  • SPDM support hardware: 269 kg
  • HPGA oxygen tank: 552 kg
  • ATA-2 ammonia tank: 772 kg
  • STP-H3 experiment package (set of US DoD Space Test Program experiments, including thermal control systems and space environment sensors): 500 kg
• Total Payload: 16,554 kg

Transferred a Pump Flow Control Subassembly over to Dextre stowed failed PFCS on ESP-1, Replaced camera and lights used to film NASA TV, Replaced Space to Ground Transceiver Controller, Performed get aheads to Install handrails on Radiator Grapple Bars on S1, Removed thermal blankets and MLI from two Direct Current Switching Units on ESP-2, Prepped the Flex Hose Rotary Coupler on S1 for replacement. Spacewalk suffered a 7-minute delay because of a water leak which formed ice crystals inside the airlock.