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Comment by saalweachter | Hacker News Reader

You know, we're probably capable of landing on a landing pad on the moon, now.

Apollo 11/Eagle landed something like 4 miles off from their target site, but SpaceX nowadays routinely lands on target.

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Probably, but do we want to keep going back to the same spot?

... and then Apollo 12 targeted one of the earlier Surveyor probes (which had successfully done its own automated moon landing in the mid-1960s!), and the guidance system had it coming down very close to the earlier probe -- astronaut Pete Conrad manually overrode it to make sure they stayed a safe distance away.

There had been upgrades to software and procedures since Apollo 11 -- most notably, a new guidance parameter the astronauts could enter ("noun 69") to correct for deviations between the planned lunar orbit and the one in which the spacecraft actually was, before descent.

https://www.forbes.com/sites/davidmindell/2019/11/19/apollo-...

Apollo 11 isn't really the proper comparison to make, though; more precise landings were goals of later missions.

Fair enough; Apollo 12 landed within walking distance of the Surveyor probe, but I don't have enough information to know whether 535 feet from the probe was exactly on target, or hundreds of feet off target. So maybe we could have landed on a pad 50 years ago, too?

Apollo 11/Eagle was deliberately piloted away from the initial landing site because the pilot did not think the original location was safe. So until a perfectly placed target for a robot to land on like SpaceX does (which seems only likely if establishing a sort of base), the robots will need to be made smarter about landing or built to be more agile on landing on less than ideal sites.

A launch and return to the same rotating body is surely a simpler maneuver than orbital transfer to a different spinning body and landing. No doubt we are better at it but I’m not sure earth landings are an accurate analog.

Nah, you can't really compare them like that. And landing on a planet with an atmosphere is completely different from a moon without one.

Landing on the moon is easier. It just looks hard because it's so expensive to get there that you don't get many attempts.

That depends on how much atmosphere. Mars has enough atmosphere to be annoying, but not really enough to be useful. Winds can throw you off target, but you can't use a parachute for a soft landing.

That's not true. Many (most?) Mars missions with Landers have used parachutes, though they are not sufficient for a true soft landing.

I'm not an expert but I think landing on Mars with no atmosphere would be harder, because you'd need so much more fuel for a controlled descent.

> SpaceX nowadays routinely lands on target

On the moon?

No SpaceX-made craft has landed on the moon.

The article mentions that SpaceX has landed on the moon once, and tipped over. The moon is harder to land on then the Earth - less gravity and atmosphere.

I haven’t read the article (paywall) so I can’t be sure, but I believe the article is referring to the Intuitive Machines lunar landing.

SpaceX has not yet attempted to land anything on the moon.

SpaceX launched Odysseus. If you want to argue that this doesn't count as SpaceX landing, that's fine, but then it's even less evidence of Spacex's ability to land anything on the moon standing up.

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