Luna 15 is successful

Overview
What happens if Luna 15 returned lunar samples to Earth before Apollo 11 did?

Timeline
1957: USSR launched the first satellite Sputnik 1.

1961: USSR cosmonaut Yuri Gagarin became the first man in space.

1966: Soviet rocket designer Sergei Korolev didn't die in an operation. Point of divergence.

July 1969: Luna 15 successfully landed on the Moon as the NASA astronauts Neil Armstrong and Buzz Aldrin is walking on the Moon. Eventually Luna 15 will return the lunar samples to Earth hours before Apollo 11 did, causing much embarrassment in USA.

1971: USSR launched the first space station Salyut 1.

1973: USA launched their space station Skylab.

1975: NASA's Skylab B artificial gravity space station is launched, which is based on the Self-Deploying Space Station design. This is seen as another big lead against the Soviet Union in the Space Race.

1977: The twin Voyager mission is launched by U.S.

1981: American space shuttle "Columbia" is launched.

1986: Space Shuttle "Challenger" exploded during launch.

1991: The USSR ceased to exist.

1995: NASA's Comet Rendezvous Asteroid Flyby mission is launched to Comet Kopff.

2003: Europa Orbiter is sent to the namesake Jovian moon with the aid of a Space Shuttle. Concurrently NASA launched Deep Space 4 to comet Tempel 1. Unfortunately the Columbia space shuttle tragedy happened as in OTL.

2008: A robotic NASA mission successfully retrieved sample from Mars.

2015: Laser Interferometer Gravitational-Wave Observatory (LIGO) discovered the first gravitational waves. NASA's Orion spacecraft reaches ISS after a long hiatus.

2016: Donald John Trump is being elected as the President of the United States. Exoplanet Proxima Centauri b is discovered. LIGO announced the gravitational wave discovery as in OTL.