United States and Soviet Union competed to be the first nations to land people on Earth’s natural satellite, while many other nations and private companies also made attempts at reaching lunar territory.
Moon landings present unique challenges due to its weak gravity – just one-sixth as strong as on Earth – but absence of atmosphere.
Spacecraft
Six spacecraft from the Soviet Union (Interkosmos), United States (NASA), China (CNSA), India (ISRO) and Japan’s JAXA have successfully reached the Moon; three additional private/commercial missions including Israel’s Beresheet, Hakuto-R and Intuitive Machines Odysseus also successfully touched down on its surface.
Apollo 11 crew made history on 20 July 1969 by landing the US-built Apollo Lunar Module onto the moon using the Saturn V rocket and creating Tranquility Base during their seven day stay on Tranquility Base.
Lunar Reconnaissance Orbiter provided a wealth of data about the Moon that enabled many groundbreaking discoveries. Now in orbit, its successor Lunar Orbiter Mission is currently exploring it from above while its lander and rover will explore the far side in 2024.
Rockets
Rockets generate thrust by reacting with explosive chemicals to release explosive fumes that burn and push in one direction – much like wind on Earth!). When these fumes burn off they push in another direction (the opposite to what would occur naturally).
Every component on a spacecraft adds weight and increases fuel usage; astronauts should therefore only bring items essential for their mission.
Eagle, Armstrong and Aldrin’s home for 21.5 hours on the Moon, weighed less than 3 tons. Surveyor 6’s rocket launched it; this needed to carry science equipment as well as supplies for astronauts. Now NASA’s Space Launch System rocket and Orion crew capsule are set to test themselves on lunar surfaces as an important practice run before any future trips to Mars that require even greater commitment on our part.
Orbits
To reach the Moon, rockets propel spacecraft into orbit around Earth. From there on out, gravity keeps their trajectory steady – just like throwing a ball – it takes energy to launch it upward, but then once released will follow its own curved path back towards earth.
Low Earth Orbit (LEO) is the go-to orbit for most manned missions, providing satellites with closer access to Earth for imaging and communications purposes.
At least, it would seem so, since distance from Earth to the Moon varies quite drastically due to its irregular orbit around Earth and can come close or further from it at certain points (known as perigee ) than at others ( apogee). This phenomenon causes it to appear 10% larger and 30% brighter than expected!
Landings
Space exploration aims to gather data on other planets, including the Moon. This knowledge helps inform better decisions regarding how best to explore them as well as future missions to them.
Surveyor 1 was the inaugural spacecraft to land on the Moon, in Sinus Medii. Following its landing, it took pictures and soil samples before moving forward with its examination of where it landed for signs of impact craters.
NASA launched their Lunar Reconnaissance Orbiter (LRO) spacecraft the following year and conducted several missions there, such as providing high-resolution images of the far side of the Moon during a flyby and testing out various experiments and CubeSats that would help demonstrate remote operation of small payloads.