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

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

#221

Post by maccam94 »

GCU-Empiricist wrote: post #68
maccam94 wrote: post #53

Earlier quoted context omitted.

I really want to see asteroid mining prioritized, as well as a space station capable of permanent human habitation (either partial or full gravity). A space station is also preferable to another planet for our next big space endeavor IMO because it is easier to get materials to and from it (no extra gravity well to deal with). Also, I feel like a lot of people think "ah, everything has to be done differently because…

It'll happen when there's a business model that reduces the operating margin for a company. My best guess is this will be when the price for lithium or trans-uranics goes up significantly, or some engineering process requires microgravity conditions.

My point is that just getting projects started in space has a high barrier of entry due to the expense of moving personnel and structures into space. If we had permanent residents there, and the ability to manufacture the structures in space, it would become cost effective to build those specialized zero-G factories. It's unlikely that any single company will pony up the cost for that space habitat/construction facility, since it will be the most expensive structure to build.

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

#222

Post by flukus »

ams6110 wrote: post #87
jpatokal wrote: post #60

Earlier quoted context omitted.

Sure, but sharing right of way with cars is slow, dangerous and generally avoided whenever feasible.

Yes, has all the disadvantages of a bus system with the added disadvantage that changing routes is tremendously expensive since you need to lay new track.

> with the added disadvantage that changing routes is tremendously expensive since you need to lay new track.

That disadvantage is actually a good thing when you're buying real estate, a bus route can change but my tram stop has much more permanence.

It also doesn't have to be an either/or thing, my local trams are dedicated in large parts but on road where congestion is lighter.

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

#223

Post by clacke2 »

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…

> Uber-like services

That's a convoluted, backwards and very funny way of saying "taxi". :-D

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

#224

Post by gozur88 »

coliveira wrote: post #148
gozur88 wrote: post #14

Earlier quoted context omitted.

We would never have done it the first time if not for military competition with the USSR.

The USA already has bombs, no science is being used to produce more of the same.

We had bombs before the space race, too. That doesn't mean it wasn't, in essence, a military competition.

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

#225

Post by gozur88 »

bonesss wrote: post #62
make3 wrote: post #36

Earlier quoted context omitted.

Except that back then they couldn't see what was in the new world. Now we can (on the moon), and know that there isn't much. Also, it would take a lot more than just sending people there for them to be mostly be self sufficient like in the 17th century, because: - there is no oxygen, - there is no food, - there is no water, - there is no magnetosphere.

We can make [oxygen from moon rocks]( https://phys.org/news/2009-08-scientists-oxygen-moon.html ). There is [water on the moon]( https://www.nasa.gov/mission_pages/Mini-RF/multimedia/featur... ). With oxygen, water, and power, we can make food. Appropriate radiation shielding is a matter of construction, which could occur on the moon itself using local materials ideally, or building underground enough to be shielded.…

Yes, yes, we can do all that stuff. But why would we? What justifies the expense?

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

#226

Post by alexnewman »

mruniverse wrote: post #16
alexnewman wrote: post #11

What evidence leads you to believe that nasa is currently run as efficiently or as innovative as during say the first half of Apollo. Everything I’ve heard from people who worked there is that it’s generally become more and more of nightmare

You ask for evidence, then follow up with "I heard from people..."?

Ahh, I am glad you asked. I actually have been lucky enough to work at two small spacecraft companies. I am not an aerospace engineer but I talk to people who are and interact with tons of x-nasa people. Also, my weirdo comments aren't my own. Checkout the omega tau series, especially http://omegataupodcast.net/218-a-life-in-apollo/

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

#227

Post by alexnewman »

aeorgnoieang wrote: post #149
mruniverse wrote: post #16

Earlier quoted context omitted.

You ask for evidence, then follow up with "I heard from people..."?

People telling you things is evidence.

Actually,that's a good point! People telling me things isn't exactly evidence. I wonder what pure evidence would look like?

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

#228

Post by maccam94 »

TeMPOraL wrote: post #194
maccam94 wrote: post #56

Earlier quoted context omitted.

I'm not sure what the delta-V is like to get materials from an asteroid vs the Moon, but I'd expect there is much more variety of resources on asteroids. I think an orbital station is also more attractive than the Moon from a delta-V standpoint.

> but I'd expect there is much more variety of resources on asteroids As far as I understand, in terms of easy access, yes - in particular resources that on planemos tended to sink to the core as the object formed and cooled down. > I think an orbital station is also more attractive than the Moon from a delta-V standpoint. LEO? Not necessarily. You still need to burn your way up the pretty steep gravity well. Both th…

Interesting, I didn't realize Earth's gravity was still so strong at 500km up. Getting payloads to the station from space would still be cheaper because we could rely on aerobraking, but accelerating mass to Earth escape velocity from LEO would require an extra 1km/s of delta-V compared to the Moon. I think the Moon might make sense if we can mine significant materials from it, but I haven't read much about what's there.

Source: https://en.wikipedia.org/wiki/Delta-v_budget#/media/File:Del...

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

#229

Post by TeMPOraL »

maccam94 wrote: post #228
TeMPOraL wrote: post #194

Earlier quoted context omitted.

> but I'd expect there is much more variety of resources on asteroids As far as I understand, in terms of easy access, yes - in particular resources that on planemos tended to sink to the core as the object formed and cooled down. > I think an orbital station is also more attractive than the Moon from a delta-V standpoint. LEO? Not necessarily. You still need to burn your way up the pretty steep gravity well. Both th…

Interesting, I didn't realize Earth's gravity was still so strong at 500km up. Getting payloads to the station from space would still be cheaper because we could rely on aerobraking, but accelerating mass to Earth escape velocity from LEO would require an extra 1km/s of delta-V compared to the Moon. I think the Moon might make sense if we can mine significant materials from it, but I haven't read much about what's th…

Yup, our well is steep :).

See also this subway-style ∆v map of our system (inspired by a similar map for Kerbal Space Program): http://i.imgur.com/AAGJvD1.png. I feel it would work great as a poster on a wall.

The map really brings home the point that "Low Earth Orbit is halfway to anywhere in the Solar System".

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

#230

Post by SAI_Peregrinus »

deanCommie wrote: post #209
smitherfield wrote: post #111

Earlier quoted context omitted.

The Netherlands is approximately the same land area and population density as the NYC metropolitan area[1], so it is (as you say) a very different environment from the entire US or even Spain. [1] https://upload.wikimedia.org/wikipedia/commons/thumb/7/72/NY...

That's a bit of an exaggeration. Here are the areas overlaid: https://imgur.com/a/s9pq7 It's more like the area from New York to Boston

Well, since smitherfield used the CSA (combined statistical area) it's actually rather close. 34,493 km^2 for the New York CSA, while Netherlands is 41,543 km^2. So about 83% of the size of the Netherlands.
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