Were there any unmanned expeditions to the moon that returned to Earth prior to Apollo?Why didn't the Apollo program do an uncrewed landing/ascent rehearsal?What gave NASA the confidence for a translunar injection in Apollo 8?Could an Apollo LM land uncrewed?Why was the Saturn V considered to be human-rated after Apollo 6?How was dust-mitigation addressed during the Apollo program?If the Apollo mandate were delivered today, would the mission vehicle(s) and profile be similar?Have there been any photos taken of a total Earth-Sun eclipse from the Moon, or its vicinity?Would the Saturn V have been able to send more mass to TLI if it had a lower earth parking orbit?What is the case for human presence on the Moon?Were the Apollo lunar ALSEP transmitter signals ever analyzed or used after the experiments were shut down?How could an object barely exceeding escape velocity from the Moon eventually reach the Earth?Have there been long-term observations of the effects of lunar exposure to equipment?Will it be possible to see BFR approaching the moon from earth, with naked eye?What are NASA's dozen payloads for the Moon that will be ready for launch by the end this year? (2019)

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Were there any unmanned expeditions to the moon that returned to Earth prior to Apollo?


Why didn't the Apollo program do an uncrewed landing/ascent rehearsal?What gave NASA the confidence for a translunar injection in Apollo 8?Could an Apollo LM land uncrewed?Why was the Saturn V considered to be human-rated after Apollo 6?How was dust-mitigation addressed during the Apollo program?If the Apollo mandate were delivered today, would the mission vehicle(s) and profile be similar?Have there been any photos taken of a total Earth-Sun eclipse from the Moon, or its vicinity?Would the Saturn V have been able to send more mass to TLI if it had a lower earth parking orbit?What is the case for human presence on the Moon?Were the Apollo lunar ALSEP transmitter signals ever analyzed or used after the experiments were shut down?How could an object barely exceeding escape velocity from the Moon eventually reach the Earth?Have there been long-term observations of the effects of lunar exposure to equipment?Will it be possible to see BFR approaching the moon from earth, with naked eye?What are NASA's dozen payloads for the Moon that will be ready for launch by the end this year? (2019)






.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;








22












$begingroup$


Apollo 8 orbited the moon, and obviously Apollo 11 landed. I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth? It seems like a big jump to suddenly send manned ships there.










share|improve this question









$endgroup$













  • $begingroup$
    This is an interesting question and makes me wonder 1) would all of that have been possible without the Apollo guidance computer and IMU(s), and 2) would those have functioned reliably without the humans on board tending to them?
    $endgroup$
    – uhoh
    Aug 1 at 1:26







  • 3




    $begingroup$
    @uhoh AGC worked well enough controlled from the ground on Apollo 4 and 6.
    $endgroup$
    – Russell Borogove
    Aug 1 at 2:11










  • $begingroup$
    @RussellBorogove thanks, that's something to think/ask about ;-)
    $endgroup$
    – uhoh
    Aug 1 at 3:54







  • 7




    $begingroup$
    Near duplicate of Why didn't the Apollo program do an uncrewed landing/ascent rehearsal? -- but I like my answer here better. 😉
    $endgroup$
    – Russell Borogove
    Aug 1 at 14:22











  • $begingroup$
    when lindberg flew to europe he took enormous risks given the time and period. without men daring nothing is really possible
    $endgroup$
    – JP VDB
    Aug 2 at 15:34

















22












$begingroup$


Apollo 8 orbited the moon, and obviously Apollo 11 landed. I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth? It seems like a big jump to suddenly send manned ships there.










share|improve this question









$endgroup$













  • $begingroup$
    This is an interesting question and makes me wonder 1) would all of that have been possible without the Apollo guidance computer and IMU(s), and 2) would those have functioned reliably without the humans on board tending to them?
    $endgroup$
    – uhoh
    Aug 1 at 1:26







  • 3




    $begingroup$
    @uhoh AGC worked well enough controlled from the ground on Apollo 4 and 6.
    $endgroup$
    – Russell Borogove
    Aug 1 at 2:11










  • $begingroup$
    @RussellBorogove thanks, that's something to think/ask about ;-)
    $endgroup$
    – uhoh
    Aug 1 at 3:54







  • 7




    $begingroup$
    Near duplicate of Why didn't the Apollo program do an uncrewed landing/ascent rehearsal? -- but I like my answer here better. 😉
    $endgroup$
    – Russell Borogove
    Aug 1 at 14:22











  • $begingroup$
    when lindberg flew to europe he took enormous risks given the time and period. without men daring nothing is really possible
    $endgroup$
    – JP VDB
    Aug 2 at 15:34













22












22








22


1



$begingroup$


Apollo 8 orbited the moon, and obviously Apollo 11 landed. I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth? It seems like a big jump to suddenly send manned ships there.










share|improve this question









$endgroup$




Apollo 8 orbited the moon, and obviously Apollo 11 landed. I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth? It seems like a big jump to suddenly send manned ships there.







the-moon uncrewed-spaceflight






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Aug 1 at 1:05









Joe BobJoe Bob

1211 silver badge3 bronze badges




1211 silver badge3 bronze badges














  • $begingroup$
    This is an interesting question and makes me wonder 1) would all of that have been possible without the Apollo guidance computer and IMU(s), and 2) would those have functioned reliably without the humans on board tending to them?
    $endgroup$
    – uhoh
    Aug 1 at 1:26







  • 3




    $begingroup$
    @uhoh AGC worked well enough controlled from the ground on Apollo 4 and 6.
    $endgroup$
    – Russell Borogove
    Aug 1 at 2:11










  • $begingroup$
    @RussellBorogove thanks, that's something to think/ask about ;-)
    $endgroup$
    – uhoh
    Aug 1 at 3:54







  • 7




    $begingroup$
    Near duplicate of Why didn't the Apollo program do an uncrewed landing/ascent rehearsal? -- but I like my answer here better. 😉
    $endgroup$
    – Russell Borogove
    Aug 1 at 14:22











  • $begingroup$
    when lindberg flew to europe he took enormous risks given the time and period. without men daring nothing is really possible
    $endgroup$
    – JP VDB
    Aug 2 at 15:34
















  • $begingroup$
    This is an interesting question and makes me wonder 1) would all of that have been possible without the Apollo guidance computer and IMU(s), and 2) would those have functioned reliably without the humans on board tending to them?
    $endgroup$
    – uhoh
    Aug 1 at 1:26







  • 3




    $begingroup$
    @uhoh AGC worked well enough controlled from the ground on Apollo 4 and 6.
    $endgroup$
    – Russell Borogove
    Aug 1 at 2:11










  • $begingroup$
    @RussellBorogove thanks, that's something to think/ask about ;-)
    $endgroup$
    – uhoh
    Aug 1 at 3:54







  • 7




    $begingroup$
    Near duplicate of Why didn't the Apollo program do an uncrewed landing/ascent rehearsal? -- but I like my answer here better. 😉
    $endgroup$
    – Russell Borogove
    Aug 1 at 14:22











  • $begingroup$
    when lindberg flew to europe he took enormous risks given the time and period. without men daring nothing is really possible
    $endgroup$
    – JP VDB
    Aug 2 at 15:34















$begingroup$
This is an interesting question and makes me wonder 1) would all of that have been possible without the Apollo guidance computer and IMU(s), and 2) would those have functioned reliably without the humans on board tending to them?
$endgroup$
– uhoh
Aug 1 at 1:26





$begingroup$
This is an interesting question and makes me wonder 1) would all of that have been possible without the Apollo guidance computer and IMU(s), and 2) would those have functioned reliably without the humans on board tending to them?
$endgroup$
– uhoh
Aug 1 at 1:26





3




3




$begingroup$
@uhoh AGC worked well enough controlled from the ground on Apollo 4 and 6.
$endgroup$
– Russell Borogove
Aug 1 at 2:11




$begingroup$
@uhoh AGC worked well enough controlled from the ground on Apollo 4 and 6.
$endgroup$
– Russell Borogove
Aug 1 at 2:11












$begingroup$
@RussellBorogove thanks, that's something to think/ask about ;-)
$endgroup$
– uhoh
Aug 1 at 3:54





$begingroup$
@RussellBorogove thanks, that's something to think/ask about ;-)
$endgroup$
– uhoh
Aug 1 at 3:54





7




7




$begingroup$
Near duplicate of Why didn't the Apollo program do an uncrewed landing/ascent rehearsal? -- but I like my answer here better. 😉
$endgroup$
– Russell Borogove
Aug 1 at 14:22





$begingroup$
Near duplicate of Why didn't the Apollo program do an uncrewed landing/ascent rehearsal? -- but I like my answer here better. 😉
$endgroup$
– Russell Borogove
Aug 1 at 14:22













$begingroup$
when lindberg flew to europe he took enormous risks given the time and period. without men daring nothing is really possible
$endgroup$
– JP VDB
Aug 2 at 15:34




$begingroup$
when lindberg flew to europe he took enormous risks given the time and period. without men daring nothing is really possible
$endgroup$
– JP VDB
Aug 2 at 15:34










2 Answers
2






active

oldest

votes


















48












$begingroup$


I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth?




There were no uncrewed round-trip missions to the moon prior to Apollo 11.



Several one-way missions landed safely on the moon without crew before 1969, but did not return, including the American Surveyor series. The first of these, Surveyor 1, landed on the moon on June 2, 1966.



In 1970, the first robotic round-trip mission, the USSR's Luna 16, returned samples from the moon.



There weren't any huge technical obstacles to robotic lunar round-trip missions. The Luna round-trips used a clever return trajectory that required only a single burn from the moon's surface with no course corrections afterwards, but that technique constrained when and where they could land on the moon; a multiple-burn return would have required a little more sophistication in the probe's guidance and navigation system (and thus more mass and cost), but it wouldn't have been impossible to do pre-Apollo-11.



Returning from the moon takes a vehicle several times larger than one that just needs to get there; if you don't do a lunar orbit rendezvous like Apollo did, then you need to carry all the fuel for your return journey all the way to the moon's surface. Luna 16 was more than 5 times as massive as Surveyor 1, for example, requiring a 700-ton Proton booster to go to the moon instead of a 140-ton Atlas-Centaur.



Lunar orbit rendezvous offers a path to a lunar landing mission with a smaller vehicle at the cost of additional mission complexity, and automatic docking had been demonstrated by the USSR in 1967.



The USSR's lunar landing plan would possibly have landed one LK uncrewed as a backup, followed by a second LK with a single crew member, but they never got the necessary N1 booster to work. The LK itself had a backup ascent engine, so this plan provides 8 times as many ascent engines per crew member as Apollo. They clearly didn't want to strand a cosmonaut on the moon.




It seems like a big jump to suddenly send manned ships there.




It would have been technically feasible to land an Apollo LM (with some modifications) uncrewed. However, one of the major lessons of the X-15 program was that the combination of automation and human capabilities in a complex system was far more reliable than either human or automation alone. If, for example, Apollo 10 had flown its LM to the surface without a crew, it would have had substantial risk of crashing (having no way to know if it was coming down in a field of boulders) and the program would have missed out on the first-hand observations of the crew.



As with other apparently-risky steps taken in the Apollo program (particularly Apollo 8, discussed here and here), skipping an unmanned landing attempt was a calculated risk to save time and money.






share|improve this answer











$endgroup$










  • 3




    $begingroup$
    This is a superb answer!
    $endgroup$
    – Organic Marble
    Aug 1 at 2:47






  • 1




    $begingroup$
    I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
    $endgroup$
    – Innovine
    Aug 1 at 11:53







  • 1




    $begingroup$
    @Innovine And in fact the USSR did a remote control docking in ‘67.
    $endgroup$
    – Russell Borogove
    Aug 1 at 13:23






  • 2




    $begingroup$
    @user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
    $endgroup$
    – Russell Borogove
    Aug 2 at 13:57






  • 2




    $begingroup$
    @RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
    $endgroup$
    – user
    Aug 2 at 14:01


















8












$begingroup$

No. NASA was focused on manned missions. The unmanned Surveyor series proved that a Moon landing was possible, and launching from the lunar surface wasn't considered risky enough that an unmanned trial run was considered worth doing.



The Soviet Union took two shots at it: an unnamed mission that failed on launch in June 1969 and Luna 15 (crashed into the Moon 13 hours after the start of Armstrong's moonwalk), but the first successful unmanned sample-return mission was Luna 16, in September of 1970.






share|improve this answer









$endgroup$










  • 4




    $begingroup$
    Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
    $endgroup$
    – Innovine
    Aug 1 at 16:14













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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









48












$begingroup$


I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth?




There were no uncrewed round-trip missions to the moon prior to Apollo 11.



Several one-way missions landed safely on the moon without crew before 1969, but did not return, including the American Surveyor series. The first of these, Surveyor 1, landed on the moon on June 2, 1966.



In 1970, the first robotic round-trip mission, the USSR's Luna 16, returned samples from the moon.



There weren't any huge technical obstacles to robotic lunar round-trip missions. The Luna round-trips used a clever return trajectory that required only a single burn from the moon's surface with no course corrections afterwards, but that technique constrained when and where they could land on the moon; a multiple-burn return would have required a little more sophistication in the probe's guidance and navigation system (and thus more mass and cost), but it wouldn't have been impossible to do pre-Apollo-11.



Returning from the moon takes a vehicle several times larger than one that just needs to get there; if you don't do a lunar orbit rendezvous like Apollo did, then you need to carry all the fuel for your return journey all the way to the moon's surface. Luna 16 was more than 5 times as massive as Surveyor 1, for example, requiring a 700-ton Proton booster to go to the moon instead of a 140-ton Atlas-Centaur.



Lunar orbit rendezvous offers a path to a lunar landing mission with a smaller vehicle at the cost of additional mission complexity, and automatic docking had been demonstrated by the USSR in 1967.



The USSR's lunar landing plan would possibly have landed one LK uncrewed as a backup, followed by a second LK with a single crew member, but they never got the necessary N1 booster to work. The LK itself had a backup ascent engine, so this plan provides 8 times as many ascent engines per crew member as Apollo. They clearly didn't want to strand a cosmonaut on the moon.




It seems like a big jump to suddenly send manned ships there.




It would have been technically feasible to land an Apollo LM (with some modifications) uncrewed. However, one of the major lessons of the X-15 program was that the combination of automation and human capabilities in a complex system was far more reliable than either human or automation alone. If, for example, Apollo 10 had flown its LM to the surface without a crew, it would have had substantial risk of crashing (having no way to know if it was coming down in a field of boulders) and the program would have missed out on the first-hand observations of the crew.



As with other apparently-risky steps taken in the Apollo program (particularly Apollo 8, discussed here and here), skipping an unmanned landing attempt was a calculated risk to save time and money.






share|improve this answer











$endgroup$










  • 3




    $begingroup$
    This is a superb answer!
    $endgroup$
    – Organic Marble
    Aug 1 at 2:47






  • 1




    $begingroup$
    I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
    $endgroup$
    – Innovine
    Aug 1 at 11:53







  • 1




    $begingroup$
    @Innovine And in fact the USSR did a remote control docking in ‘67.
    $endgroup$
    – Russell Borogove
    Aug 1 at 13:23






  • 2




    $begingroup$
    @user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
    $endgroup$
    – Russell Borogove
    Aug 2 at 13:57






  • 2




    $begingroup$
    @RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
    $endgroup$
    – user
    Aug 2 at 14:01















48












$begingroup$


I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth?




There were no uncrewed round-trip missions to the moon prior to Apollo 11.



Several one-way missions landed safely on the moon without crew before 1969, but did not return, including the American Surveyor series. The first of these, Surveyor 1, landed on the moon on June 2, 1966.



In 1970, the first robotic round-trip mission, the USSR's Luna 16, returned samples from the moon.



There weren't any huge technical obstacles to robotic lunar round-trip missions. The Luna round-trips used a clever return trajectory that required only a single burn from the moon's surface with no course corrections afterwards, but that technique constrained when and where they could land on the moon; a multiple-burn return would have required a little more sophistication in the probe's guidance and navigation system (and thus more mass and cost), but it wouldn't have been impossible to do pre-Apollo-11.



Returning from the moon takes a vehicle several times larger than one that just needs to get there; if you don't do a lunar orbit rendezvous like Apollo did, then you need to carry all the fuel for your return journey all the way to the moon's surface. Luna 16 was more than 5 times as massive as Surveyor 1, for example, requiring a 700-ton Proton booster to go to the moon instead of a 140-ton Atlas-Centaur.



Lunar orbit rendezvous offers a path to a lunar landing mission with a smaller vehicle at the cost of additional mission complexity, and automatic docking had been demonstrated by the USSR in 1967.



The USSR's lunar landing plan would possibly have landed one LK uncrewed as a backup, followed by a second LK with a single crew member, but they never got the necessary N1 booster to work. The LK itself had a backup ascent engine, so this plan provides 8 times as many ascent engines per crew member as Apollo. They clearly didn't want to strand a cosmonaut on the moon.




It seems like a big jump to suddenly send manned ships there.




It would have been technically feasible to land an Apollo LM (with some modifications) uncrewed. However, one of the major lessons of the X-15 program was that the combination of automation and human capabilities in a complex system was far more reliable than either human or automation alone. If, for example, Apollo 10 had flown its LM to the surface without a crew, it would have had substantial risk of crashing (having no way to know if it was coming down in a field of boulders) and the program would have missed out on the first-hand observations of the crew.



As with other apparently-risky steps taken in the Apollo program (particularly Apollo 8, discussed here and here), skipping an unmanned landing attempt was a calculated risk to save time and money.






share|improve this answer











$endgroup$










  • 3




    $begingroup$
    This is a superb answer!
    $endgroup$
    – Organic Marble
    Aug 1 at 2:47






  • 1




    $begingroup$
    I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
    $endgroup$
    – Innovine
    Aug 1 at 11:53







  • 1




    $begingroup$
    @Innovine And in fact the USSR did a remote control docking in ‘67.
    $endgroup$
    – Russell Borogove
    Aug 1 at 13:23






  • 2




    $begingroup$
    @user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
    $endgroup$
    – Russell Borogove
    Aug 2 at 13:57






  • 2




    $begingroup$
    @RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
    $endgroup$
    – user
    Aug 2 at 14:01













48












48








48





$begingroup$


I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth?




There were no uncrewed round-trip missions to the moon prior to Apollo 11.



Several one-way missions landed safely on the moon without crew before 1969, but did not return, including the American Surveyor series. The first of these, Surveyor 1, landed on the moon on June 2, 1966.



In 1970, the first robotic round-trip mission, the USSR's Luna 16, returned samples from the moon.



There weren't any huge technical obstacles to robotic lunar round-trip missions. The Luna round-trips used a clever return trajectory that required only a single burn from the moon's surface with no course corrections afterwards, but that technique constrained when and where they could land on the moon; a multiple-burn return would have required a little more sophistication in the probe's guidance and navigation system (and thus more mass and cost), but it wouldn't have been impossible to do pre-Apollo-11.



Returning from the moon takes a vehicle several times larger than one that just needs to get there; if you don't do a lunar orbit rendezvous like Apollo did, then you need to carry all the fuel for your return journey all the way to the moon's surface. Luna 16 was more than 5 times as massive as Surveyor 1, for example, requiring a 700-ton Proton booster to go to the moon instead of a 140-ton Atlas-Centaur.



Lunar orbit rendezvous offers a path to a lunar landing mission with a smaller vehicle at the cost of additional mission complexity, and automatic docking had been demonstrated by the USSR in 1967.



The USSR's lunar landing plan would possibly have landed one LK uncrewed as a backup, followed by a second LK with a single crew member, but they never got the necessary N1 booster to work. The LK itself had a backup ascent engine, so this plan provides 8 times as many ascent engines per crew member as Apollo. They clearly didn't want to strand a cosmonaut on the moon.




It seems like a big jump to suddenly send manned ships there.




It would have been technically feasible to land an Apollo LM (with some modifications) uncrewed. However, one of the major lessons of the X-15 program was that the combination of automation and human capabilities in a complex system was far more reliable than either human or automation alone. If, for example, Apollo 10 had flown its LM to the surface without a crew, it would have had substantial risk of crashing (having no way to know if it was coming down in a field of boulders) and the program would have missed out on the first-hand observations of the crew.



As with other apparently-risky steps taken in the Apollo program (particularly Apollo 8, discussed here and here), skipping an unmanned landing attempt was a calculated risk to save time and money.






share|improve this answer











$endgroup$




I'm wondering if there were any test missions to get unmanned ships to the moon and safely back to Earth?




There were no uncrewed round-trip missions to the moon prior to Apollo 11.



Several one-way missions landed safely on the moon without crew before 1969, but did not return, including the American Surveyor series. The first of these, Surveyor 1, landed on the moon on June 2, 1966.



In 1970, the first robotic round-trip mission, the USSR's Luna 16, returned samples from the moon.



There weren't any huge technical obstacles to robotic lunar round-trip missions. The Luna round-trips used a clever return trajectory that required only a single burn from the moon's surface with no course corrections afterwards, but that technique constrained when and where they could land on the moon; a multiple-burn return would have required a little more sophistication in the probe's guidance and navigation system (and thus more mass and cost), but it wouldn't have been impossible to do pre-Apollo-11.



Returning from the moon takes a vehicle several times larger than one that just needs to get there; if you don't do a lunar orbit rendezvous like Apollo did, then you need to carry all the fuel for your return journey all the way to the moon's surface. Luna 16 was more than 5 times as massive as Surveyor 1, for example, requiring a 700-ton Proton booster to go to the moon instead of a 140-ton Atlas-Centaur.



Lunar orbit rendezvous offers a path to a lunar landing mission with a smaller vehicle at the cost of additional mission complexity, and automatic docking had been demonstrated by the USSR in 1967.



The USSR's lunar landing plan would possibly have landed one LK uncrewed as a backup, followed by a second LK with a single crew member, but they never got the necessary N1 booster to work. The LK itself had a backup ascent engine, so this plan provides 8 times as many ascent engines per crew member as Apollo. They clearly didn't want to strand a cosmonaut on the moon.




It seems like a big jump to suddenly send manned ships there.




It would have been technically feasible to land an Apollo LM (with some modifications) uncrewed. However, one of the major lessons of the X-15 program was that the combination of automation and human capabilities in a complex system was far more reliable than either human or automation alone. If, for example, Apollo 10 had flown its LM to the surface without a crew, it would have had substantial risk of crashing (having no way to know if it was coming down in a field of boulders) and the program would have missed out on the first-hand observations of the crew.



As with other apparently-risky steps taken in the Apollo program (particularly Apollo 8, discussed here and here), skipping an unmanned landing attempt was a calculated risk to save time and money.







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edited Aug 2 at 14:10

























answered Aug 1 at 1:52









Russell BorogoveRussell Borogove

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101k4 gold badges359 silver badges441 bronze badges










  • 3




    $begingroup$
    This is a superb answer!
    $endgroup$
    – Organic Marble
    Aug 1 at 2:47






  • 1




    $begingroup$
    I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
    $endgroup$
    – Innovine
    Aug 1 at 11:53







  • 1




    $begingroup$
    @Innovine And in fact the USSR did a remote control docking in ‘67.
    $endgroup$
    – Russell Borogove
    Aug 1 at 13:23






  • 2




    $begingroup$
    @user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
    $endgroup$
    – Russell Borogove
    Aug 2 at 13:57






  • 2




    $begingroup$
    @RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
    $endgroup$
    – user
    Aug 2 at 14:01












  • 3




    $begingroup$
    This is a superb answer!
    $endgroup$
    – Organic Marble
    Aug 1 at 2:47






  • 1




    $begingroup$
    I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
    $endgroup$
    – Innovine
    Aug 1 at 11:53







  • 1




    $begingroup$
    @Innovine And in fact the USSR did a remote control docking in ‘67.
    $endgroup$
    – Russell Borogove
    Aug 1 at 13:23






  • 2




    $begingroup$
    @user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
    $endgroup$
    – Russell Borogove
    Aug 2 at 13:57






  • 2




    $begingroup$
    @RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
    $endgroup$
    – user
    Aug 2 at 14:01







3




3




$begingroup$
This is a superb answer!
$endgroup$
– Organic Marble
Aug 1 at 2:47




$begingroup$
This is a superb answer!
$endgroup$
– Organic Marble
Aug 1 at 2:47




1




1




$begingroup$
I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
$endgroup$
– Innovine
Aug 1 at 11:53





$begingroup$
I think your answer should mention the tortoises on Zond 5. It's an intermediate step between unmanned craft and the manned missions, showing that life support systems could remain operational, and keeping the passengers alive long enough to survive the journey.
$endgroup$
– Innovine
Aug 1 at 11:53





1




1




$begingroup$
@Innovine And in fact the USSR did a remote control docking in ‘67.
$endgroup$
– Russell Borogove
Aug 1 at 13:23




$begingroup$
@Innovine And in fact the USSR did a remote control docking in ‘67.
$endgroup$
– Russell Borogove
Aug 1 at 13:23




2




2




$begingroup$
@user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
$endgroup$
– Russell Borogove
Aug 2 at 13:57




$begingroup$
@user That was considered by the US, but the USSR’s final plan was a one-lander LOR plan not too unlike Apollo. A return lander still has to descend and ascend safely (albeit without crew mass on the descent) then you need a whole second ship for descent only, so it’s less efficient.
$endgroup$
– Russell Borogove
Aug 2 at 13:57




2




2




$begingroup$
@RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
$endgroup$
– user
Aug 2 at 14:01




$begingroup$
@RussellBorogove I think their plan was to do the entire landing automatically. Soviet spacecraft tended to be more automated than US ones. So the first lander would be a test of the landing system, and also offer a spare craft if the ascent engine on the later manned one failed.
$endgroup$
– user
Aug 2 at 14:01













8












$begingroup$

No. NASA was focused on manned missions. The unmanned Surveyor series proved that a Moon landing was possible, and launching from the lunar surface wasn't considered risky enough that an unmanned trial run was considered worth doing.



The Soviet Union took two shots at it: an unnamed mission that failed on launch in June 1969 and Luna 15 (crashed into the Moon 13 hours after the start of Armstrong's moonwalk), but the first successful unmanned sample-return mission was Luna 16, in September of 1970.






share|improve this answer









$endgroup$










  • 4




    $begingroup$
    Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
    $endgroup$
    – Innovine
    Aug 1 at 16:14















8












$begingroup$

No. NASA was focused on manned missions. The unmanned Surveyor series proved that a Moon landing was possible, and launching from the lunar surface wasn't considered risky enough that an unmanned trial run was considered worth doing.



The Soviet Union took two shots at it: an unnamed mission that failed on launch in June 1969 and Luna 15 (crashed into the Moon 13 hours after the start of Armstrong's moonwalk), but the first successful unmanned sample-return mission was Luna 16, in September of 1970.






share|improve this answer









$endgroup$










  • 4




    $begingroup$
    Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
    $endgroup$
    – Innovine
    Aug 1 at 16:14













8












8








8





$begingroup$

No. NASA was focused on manned missions. The unmanned Surveyor series proved that a Moon landing was possible, and launching from the lunar surface wasn't considered risky enough that an unmanned trial run was considered worth doing.



The Soviet Union took two shots at it: an unnamed mission that failed on launch in June 1969 and Luna 15 (crashed into the Moon 13 hours after the start of Armstrong's moonwalk), but the first successful unmanned sample-return mission was Luna 16, in September of 1970.






share|improve this answer









$endgroup$



No. NASA was focused on manned missions. The unmanned Surveyor series proved that a Moon landing was possible, and launching from the lunar surface wasn't considered risky enough that an unmanned trial run was considered worth doing.



The Soviet Union took two shots at it: an unnamed mission that failed on launch in June 1969 and Luna 15 (crashed into the Moon 13 hours after the start of Armstrong's moonwalk), but the first successful unmanned sample-return mission was Luna 16, in September of 1970.







share|improve this answer












share|improve this answer



share|improve this answer










answered Aug 1 at 2:01









MarkMark

5,18924 silver badges37 bronze badges




5,18924 silver badges37 bronze badges










  • 4




    $begingroup$
    Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
    $endgroup$
    – Innovine
    Aug 1 at 16:14












  • 4




    $begingroup$
    Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
    $endgroup$
    – Innovine
    Aug 1 at 16:14







4




4




$begingroup$
Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
$endgroup$
– Innovine
Aug 1 at 16:14




$begingroup$
Zond 5 performed a successful circumlunar flight in '68, and its passengers, a pair of tortoises, returned safely to earth.
$endgroup$
– Innovine
Aug 1 at 16:14

















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