We are officially at T-10 days until the Apollo 11 50th anniversary!
Here are some facts about the Sea of Tranquility, the chosen landing site for our first walk on the Moon:
Mare Tranquillitatis (Sea of Tranquility)
00.67408° N latitude, 23.47297° E longitude
Named in 1651 by astronomers Francesco Grimaldi and Giovanni Battista Riccioli, the Sea of Tranquility is a large lunar basin thought to have been formed 3850—3800 million years ago during the formation of the Inner Solar System (ca., Late Heavy Bombardment). Basalts in the area date back to 3800—3200 million years ago.
For the first lunar landing, the Sea of Tranquility was chosen due to its relatively smooth and level area. However, a last minute change in the original landing site was made due to the amount of craters present. The lunar module Eagle, piloted by Neil Armstrong, landed some four miles away from the pre-planned site.
But Apollo 11 was not the first to visit this area of the Moon. On February 20, 1965, the Ranger 8 spacecraft was deliberately crashed into the surface after successfully transmitting over 7,000 photographs of the Moon in the final 23 minutes of its mission.
Surveyor 5 also landed in Mare Tranquillitatis on September 11, 1967, after transmitting 19,118 images of the Moon, and was the fifth lunar lander of the unmanned Surveyor program.
Humanity's first steps beyond Earth were taken here on July 20, 1969 at 8:18 PM UTC (4:18 PM EDT). While astronaut Michael Collins orbited above, Neil Armstrong and Buzz Aldrin set up experiments and collected 49 pounds of lunar rocks and soil — the first extraterrestrial samples returned to Earth.
Credits: @nasa; @usgs; Almagestum Novum – G. B. Riccioli, 1651.
