Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

wsj.com

Post reply on HN
Print view View original

101–110 of 246 posts

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#101

Post by valuearb »

Klathmon wrote: post #69
maccam94 wrote: post #49

Earlier quoted context omitted.

It's recently gotten way cheaper. Cost per kilogram delivered to LEO: Saturn V (used for the Moon landing mission): $8,250 Falcon 9: $2,700 (price for an expendable launch) BFR (hypothetical, in development rocket): $500

Does that scale to a full lunar mission though? Just because it's cheaper to take the bus downtown doesn't say anything about the cost of airfare to another continent.

Depends on your design. The Saturn V was big enough to launch the entire lunar stack of vehicles in one shot. Anything less than that requires in orbit assembly.

IIRC: Saturn V could put 100k pounds in lunar injection. The first SLS will be around 50k, the Falcon Heavy around 40k.

Layer versions of the SLS, should we choose to spend more tens of billions developing them, will eventually have Saturn V capabilities.

The BFR (as planned) will be the largest capacity rocket ever made. Putting 300k+ in low earth orbit. It’s designed to be refueled in orbit, so essentially it’s lunar/mars injection orbit payload caisvity is 300k+.

It’s also designed to be fully reusable, unlike the Falcon series that only reuses main boosters. So it’s claimed to be far cheaper than them, and they are already the most affordable rockets ever made.

The SLS is designed to be crushed and melted like a beer can after every launch, which is why it will cost $2B+ per launch.

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#102

Post by lmm »

golergka wrote: post #74
Al-Khwarizmi wrote: post #58

Earlier quoted context omitted.

Yes, that's a very good summary of what happened. I'm aware of those factors, but I still think we took a wrong turn. Maybe not in the US due to the population sparsity and sprawl, but in Spain and many other European countries, if we could connect every town or city of more than 10K people by either rail, light rail or tram (instead of having spent billions on highways), that would cover 80% of the population. A lar…

> A large majority wouldn't need a car, and could instead use Uber-like services for the last mile. They wouldn't need it, but I bet that majority would still want it.

In Europe? I doubt it. The car doesn't quite have the same cultural significance as a symbol of adulthood/independence here, at least not to the younger generation.

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#103

Post by paulus_magnus2 »

Economy. If Moon was made of gold it wouldn't be worth going there for it [1]. Perhaps reusable spacecraft can change that.

For strategic / military reasons (money no objective) we can achieve much more than if profit is the only motivation.

[1. need a better source?] https://space.stackexchange.com/questions/22059/if-the-moon-...

Edit:

Elon Musk: With New SpaceX Tech, Rocket Costs Will Drop By A Factor of 100

https://twitter.com/elonmusk/status/908254079092002816?ref_s...

Also analysis / spaculatoin for BFR. Keep in mind we're only talking about sending stuff to Mars, not retrieving it. http://www.thespacereview.com/article/3343/1

Edit 2 federal court set the value of the moon rocks at $50,800 per gram based on how much it cost the U.S. government to retrieve the samples between 1969 and 1972.

https://www.space.com/11804-nasa-moon-rock-sting-apollo17.ht...

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#104

Post by lmm »

ThomPete wrote: post #81

The question is why would we put a man on the moon? I grew up with Moonbase Alpha (although I am not expecting to be thrown into space by a major explosion) and want this as much as anyone else but is there any reason (mining, strategic, know benefits to research) which justifies the price?

I see it as worthwhile for the same reason that art or theoretical research is worthwhile.

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#105

Post by ThomPete »

nnq wrote: post #93
ThomPete wrote: post #81

The question is why would we put a man on the moon? I grew up with Moonbase Alpha (although I am not expecting to be thrown into space by a major explosion) and want this as much as anyone else but is there any reason (mining, strategic, know benefits to research) which justifies the price?

> is there any reason [...] which justifies the price THIS kind of thinking is our problem imho - we are living in rich times and we should start behaving as such! We have more of everything than we need. Yeah, there are children starving or dying of preventable diseases somewhere in the world, but guess what, even if we'd be 10x richer there will still be. Or we'll whip out a world war or some runaway next gen biowe…

As much as I want to agree with you I think it's a very naive way of thinking about this problem (which can sometimes be good so don't get me wrong).

I personally believe in what I call natural next steps. I.e steps that are naturally extending previous ones.

To me, the next step is making the space station much more robust.

And focusing on AI might actually be a much smarter move as it might allow us to build a secure and stable moonbase before we could do it using humans.

So it's a very complex discussion where priorities might sometimes look like they are ignoring something like a space station on the moon, but actually end up being a better choice because it will allow us to get there quicker.

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#106

Post by DennisP »

paulus_magnus2 wrote: post #103

Economy. If Moon was made of gold it wouldn't be worth going there for it [1]. Perhaps reusable spacecraft can change that. For strategic / military reasons (money no objective) we can achieve much more than if profit is the only motivation. [1. need a better source?] https://space.stackexchange.com/questions/22059/if-the-moon-... Edit: Elon Musk: With New SpaceX Tech, Rocket Costs Will Drop By A Factor of 100 https:…

Not only is that based on expendable rockets, but as your link says, the game changes if you use a mass driver to launch your payloads back to Earth.

And of course, as Andy Weir has been saying, tourism could be a major economic driver once reusable rockets get cheap enough.

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#107

Post by ThomPete »

lmm wrote: post #104
ThomPete wrote: post #81

The question is why would we put a man on the moon? I grew up with Moonbase Alpha (although I am not expecting to be thrown into space by a major explosion) and want this as much as anyone else but is there any reason (mining, strategic, know benefits to research) which justifies the price?

I see it as worthwhile for the same reason that art or theoretical research is worthwhile.

Philosophically I agree 100% but they cost a fraction of what it would cost to create a base on the moon for instance.

Someone has to pick up that bill.

I am sure we will get a base on the moon with time but technologically we aren't there yet.

Let's focus on build a solid and habitable space station then we can use some of that knowledge to establish a base on the moon. (once we have solved the resource issues)

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#108

Post by lmm »

maccam94 wrote: post #49
Animats wrote: post #43

Because, half a century later, it's not any cheaper to do it than it was then.

It's recently gotten way cheaper. Cost per kilogram delivered to LEO: Saturn V (used for the Moon landing mission): $8,250 Falcon 9: $2,700 (price for an expendable launch) BFR (hypothetical, in development rocket): $500

The Falcon 9 isn't human-rated, and cost per kilogram doesn't cover everything - putting together 10 pieces in orbit would be really expensive.

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#109

Post by walterstucco »

Al-Khwarizmi wrote: post #58
jpatokal wrote: post #54

Earlier quoted context omitted.

Classic trams and modern light rail are different beasts. Trams were popular worldwide back in the days where automobiles were far too expensive for most people and buses hadn't taken off yet, and since they were the only practical means of transport for medium distances, even small cities had massive ridership. They also ran right on the road, sharing space with cars, which was OK because there were a lot less cars…

Yes, that's a very good summary of what happened. I'm aware of those factors, but I still think we took a wrong turn. Maybe not in the US due to the population sparsity and sprawl, but in Spain and many other European countries, if we could connect every town or city of more than 10K people by either rail, light rail or tram (instead of having spent billions on highways), that would cover 80% of the population. A lar…

It would just move workers and/or students

Not a big leap forward, being the vast majority of public transport users

People that need to move outside of going back and forth from a fixed place still would prefer a car

For obvious ease

You don't bring your girlfriend by the sea at night on a tram , you don't go to visit grandma with four kids on a tram, you don't walk 5 km from the station to the place you have to go by using a tram, unless you're forced to

BTW trams are really expensive to build, expensive to ride for more than short distances and maintenance is on the public, while car maintenance is on the owners.

We need better private transport, not better public ones

They're already ok, if you enjoy suffering rush hours congestion

Re: If We Can Put a Man on the Moon, Why Can’t We Put a Man on the Moon?

#110

Post by cryptoz »

valuearb wrote: post #89
stupidcar wrote: post #77

Earlier quoted context omitted.

Your analogy makes no sense. America isn't a person, doesn't have a limited working life, and isn't going to "retire". The solution to an inefficient federal bureaucracy and a large national debt isn't to cut economically irrelevant spending in those areas where the US enjoys an actual advantage over other countries. It's to improve the bureaucracy and balance spending in meaningful ways. Unfortunately, any sane atte…

Calling this a republican problem is being willfully ignorant of the problems in our government structure. We didn’t get $21B in debt cause of republicans, or democrats, but because of congress. Congress directed NASA to spend $20B to build the SLS, a super heavy launch system built by congresses favorite contractors. It won’t be reusable at all, ever launch rocket will be burned up in the atmosphere. Each launch wil…

The problems being discussed here happen at least 2 orders of magnitude larger than you are talking about. The little NASA journey to SLS has effectively no impact on the grander US government debt or the issues causing it.

The issues causing the debt are much much bigger problems that last centuries and are largely Republican-driven. They are things like overspending on War, keeping the poor population poor (war on drugs, cutting education spending, etc), that keep the population of the US unable to earn money and pay taxes, etc.

The problems are large and structural and they are not with NASA or their decision making. They are with Republicans.

Post reply on HN