NASA’s first attempt to soft-land an unmanned space probe on another body in the solar system ends with a perfect landing: Surveyor 1 snaps photos from the moon’s surface, takes measurements of the local environment, and provides valuable engineering data about the surface that will prove helpful in constructing the much heavier Apollo lunar modules that will – it is hoped – take astronauts to the moon by the end of the decade.
The first of five Lunar Orbiter satellites is launched by NASA, on a mission to map the moon and scout out promising landing sites for the Apollo program. In addition, radiation and micrometeor collision detectors fly aboard each Lunar Orbiter to see if the design specs of the Apollo spacecraft will be adequate to protect astronauts. Lunar Orbiter 1 is the first spacecraft to send home an image of the Earth as seen from the moon. To keep it from being a navigational hazard to future spacecraft, each Lunar Orbiter deorbits and crashes into the moon after completing its survey.
The Soviet Union launches unmanned space probe Luna 11 toward the moon, the first of a new, smaller generation of Luna probes designed to survey the moon from orbit. Unlike its predecessor, Luna 11 is equipped with cameras, and like NASA’s Lunar Orbiter, Luna 11 is tasked with mapping the moon in advance of a presumed attempt to land cosmonauts there. However, an attitude control problem points Luna 11’s cameras away from the moon, unable to transmit useful imagery back to Earth. Luna 11 remains functional in orbit of the moon for six weeks.
Three days after lifting off from Earth, NASA’s Surveyor 2 robotic probe is en route to the moon when all contact is lost. Thanks to an engine failure, Surveyor 2 is left tumbling out of control, and does eventually reach the moon, slamming into the lunar dust of Copernicus Crater at a leisurely speed of 6,000 miles per hour – perfect for traversing the distance between Earth and moon in a hurry, but not so good for landing intact.
The Soviet Union launches unmanned space probe Luna 12 toward the moon, a near-identical twin of the earlier Luna 11 spacecraft. Luna 12 returns images and observations from lunar orbit for three months until its batteries are exhausted.
The second in NASA’s series of Lunar Orbiter satellites lifts off from Earth on a course for the moon. Lunar Orbiter 2 spends a full week examining the surface of the moon from orbit, sending back high-resolution TV images for mapping purposes, and to help NASA scientists and engineers select suitable landing sites for the upcoming Apollo program. Lunar Orbiter 2’s orbital path allows it to image a particularly promising plain in the Sea of Tranquility…
The Soviet Union launches unmanned space probe Luna 13 toward the moon, where it becomes the third space vehicle to successfully make a soft landing on the lunar surface. Larger than its Soviet predecessor, Luna 9, Luna 13 measures the temperature, radiation, and hardness of the moon’s surface, all useful information to have in advance of a manned landing. After operating on the lunar surface for four days, the Luna 13 lander’s batteries are exhausted and the mission is over.
The third of five Lunar Orbiter satellites is launched to the moon by NASA, and once in orbit, Lunar Orbiter 3 achieves an unmanned spaceflight first: it’s the first unmanned space probe to image another unmanned space probe (in this case, Surveyor 1, which has been on the moon since 1966). A mechanical fault prevents Lunar Orbiter 3 from returning roughly a quarter of its images to Earth.
NASA’s robotic explorer Surveyor 3 touches down safely on the moon, snapping pictures and – with an extendable scoop arm – gathering and analyzing samples of lunar soil. Its landing site, a lunar plain called the Ocean of Storms, becomes the site of a unique long-term experiment: in two years, Surveyor 3 will become the first (and, to date, only) unmanned spacecraft to be personally inspected by humans after its landing.
NASA’s fourth Lunar Orbiter satellite lifts off for its one-week trek to the moon. Placed into an orbit that takes it over the moon’s poles instead of its equator, Lunar Orbiter 4 is able to map virtually all of the near side of the moon over a period of two weeks. Plans to have Lunar Orbiter 4 map the far side are thwarted by mechanical failures and problems with the probe’s camera optics.
For the second time, one of NASA’s robotic Surveyor space probes fails to make it to the moon intact. Launched three days before, Surveyor 4 – which is, coincidentally, targeted to land in roughly the same area that previous lander Surveyor 2 failed to reach – is mere minutes from the lunar surface when contact is lost. There is no means of determining what has caused the failure, though the most likely hypothesis is an explosion of the solid fuel rockets intended to slow Surveyor 4’s descent prior to landing.
NASA’s final Lunar Orbiter satellite is sent to the moon, with a goal of completing the mapping of the moon’s surface left unfinished by mechanical issues with its predecessor. Lunar Orbiter 5 completes the mapping of the lunar far side and helps engineers and scientists determine signal coverage from the Earth-based tracking stations that will help NASA stay in contact with future Apollo missions to the moon.
Despite an in-flight fuel pressure glitch that threatens to make this the third failure for the Surveyor program, Surveyor 5 successfully touches down in the moon’s Sea of Tranquility thanks to remote in-flight reprogramming by NASA engineers. Among its objectives on the lunar surface is a precise measurement of the elements comprising the lunar soil.
NASA’s robotic explorer Surveyor 6 lands safely on the moon, taking soil samples and pictures from the surface and, for the first time, testing an alpha-scattering surface analysis device of a type that would be included on many later missions to Mars. With the conclusion of Surveyor 6’s operations, the Surveyor probes have completed all of the tasks that were prerequisites to future Apollo manned moon missions. Surveyor 6 successfully lands in the same region of the moon that Surveyors 2 and 4 failed to reach.
Surveyor 7, the last of NASA’s robotic moon landers, comes to a smooth landing on the moon’s Tycho Crater. Packed with more scientific instrument packages than any of its predecessors, Surveyor 7 studies the amount of dust kicked up by its retro rockets during landing, and lands closer to its planned target than any of the other Surveyors. Another experiment involves a test to see if a laser beam originated from Earth can be picked up by Surveyor’s cameras.
The Soviet Union launches unmanned space probe Luna 14 toward the moon, where it takes up a lunar orbit and returns scientific data on cosmic rays and gravitational variances. This is the last orbital mission of the Luna series; future Luna vehicles will be landers or landers with rovers, some with sample return capability.
The Soviet Union launches Zond 5, a Soyuz 7K-L1 command & service module intended for flight around the moon. Rather than a cosmonaut crew, however, Zond 5 has biological specimens on board, including insects, plants, bacteria, and a pair of turtles – the first living creatures from Earth to orbit the moon. The specimens are all returned safely, though Zond 5 is the second consecutive Zond flight to lose attitude control after re-entry, splashing down in the Indian Ocean rather than making the customary propulsive return to Soviet soil. American intelligence agencies are aware of the mostly successful flight, and NASA alters the Apollo manned flight schedule to attempt to put men in orbit of the moon by the end of 1968.
The Soviet Union launches an unmanned Soyuz 7K-L1 spacecraft, designated Zond 6, on a seven-day flight around the moon and back to Earth. Like Zond 5 before it, Zond 6 carries specimens of Earth animals and plants, but a rupture of the Soyuz pressure vessel results in these specimens being exposed to hard vacuum, resulting in instant death. Furthermore, the spacecraft opens and jettisons its parachutes too early, leaving it to slam into the ground at high speed. With continued glitches plaguing the Zond flights, Soviet mission planners aren’t confident enough in the 7K-L1 capsule to put cosmonauts in it for the next flight.
Moved ahead in the schedule due to ongoing difficulties with the construction of the lunar module, Apollo 8 lifts off from Cape Canaveral on a mission that represents NASA’s biggest gamble yet in the race for the moon: on only the second manned Apollo flight, astronauts Frank Borman, Jim Lovell and Bill Anders will go to the moon, orbit it in their command/service module, and return to Earth (the lunar module is still in the late stages of development). Mission planners plot out a free return trajectory – ensuring that without engines, Apollo 8 could loop around behind the moon and swing back toward home.
Broadcasting live black & white television pictures from lunar orbit on Christmas Eve, the crew of Apollo 8 delivers one of the most-watched broadcasts of 1968. As the surface of the moon rolls silently outside the windows of their command/service module, the astronauts take turns reading the first chapter of Genesis, dedicating it to “all of you on the good Earth.” After ten orbits of the moon, Apollo 8 fires its engine, putting it on a return trajectory to Earth; it splashes down safely three days later.
Apollo 10 lifts off for a dress rehearsal over the moon. Thomas Stafford, Gene Cernan and John Young fly a complete Apollo stack – both the command/service module and the lunar model – to the moon, conducting practice maneuvers in lunar orbit. Over eight days, the Apollo 10 crew does everything but land on the moon. With the mission requirements fulfilled, NASA announces that the next Apollo mission will attempt an actual landing.
The Soviet Union launches unmanned space probe Luna 15 toward the moon, the Soviet space program’s last attempt to claim a victory in the race to the moon. Intended to land on the moon and gather a core sample of lunar soil which will then be rocketed back to Earth, hopefully ahead of the arrival of lunar soil samples from the concurrent American Apollo 11 moon landing attempt, Luna 15’s lander detaches and attempts its landing on July 20th…only to crash into the moon’s surface, losing all contact with Earth, while NASA astronauts Neil Armstrong and Buzz Aldrin prepare to depart with their soil samples intact. In a rare display of international cooperation, the Soviets shared basic orbital parameters of Luna 15’s flight with NASA to avoid any navigational hazards for Apollo 11.
Apollo 11 lifts off, with astronauts Neil Armstrong, Buzz Aldrin and Michael Collins aboard. This is the first mission scheduled to attempt a landing on the moon, with Armstrong and Aldrin aboard the lunar module while Collins remains in orbit in the command/service module.
The Apollo 11 lunar module touches down in the Sea of Tranquility, a flat plain on the moon. Astronaut Neil Armstrong is the first human being to set foot on another body in the solar system, followed by “Buzz” Aldrin; the two spend roughly two and a half hours on the moon and gather nearly 50 pounds of samples of lunar soil and rock. This feat effectively ends the Cold War space race, though both the United States and the Soviet Union continue their lunar efforts: more Apollo missions are still on the schedule, and the Soviet continue trying to mount a successful launch of their giant N1 rocket.
The Soviet Union launches the Zond 7 unmanned spacecraft, an unmanned version of the Soyuz 7K-L1 space vehicle intended to take cosmonauts around the moon. Carrying no crew, this vehicle takes pictures and tests various spacecraft systems without risking human lives. Zond 7 returns to Earth using an unusual multiple-skip atmospheric re-entry profile on August 14th. If Zond 7 had been carrying a crew, this would have been the first nominal flight of the Soyuz 7K-L1 vehicle. No cosmonaut crews would reach the moon prior to the dissolution of the Soviet Union in the late 20th century.