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Water Found Deep Inside the Moon

news.nationalgeographic.com

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Re: Water Found Deep Inside the Moon

#131

Post by thescriptkiddie »

tambourine_man wrote: post #7

I've always been more excited about a Moon colony than a Mars one. I mean, compared to Mars, the Moon is ridiculously close. Many of the same benefits Musk seeks (backup for Civilization, excitement) for a fraction of the cost. Low gravity and atmosphere on a dome would be more complicated, but again, compared to Mars, it's right there . It would be a more humble and realistic first step, IMO.

I'm all for building Lunar outposts, but colonization is not really practial. Luna simply doesn't have the natural resources to sustain a civilization. Yes there is water in the regolith, but nowhere near as much as on Mars. And critically, Carbon, Nitrogen, Phosphorus, and Sulfur are only present in trace amounts. Nearly all of the elements essential to life will have to be imported, either from Earth, from Mars, or from asteroid miners. I'd love to visit, but nobody is going live there permanently any time soon.

Re: Water Found Deep Inside the Moon

#132

Post by niftich »

jacobush wrote: post #129
rory096 wrote: post #56

Earlier quoted context omitted.

>The 50% figure is from memory, and upon further reflection is probably not quite right, so take it with a grain of salt. You're actually underestimating. Mars has an atmosphere, so spacecraft can use aerobraking to significantly reduce the delta-v required to get there. The moon has no such benefit — propulsion is required all the way to the surface. The advantage of the moon, of course, is that it's not limited to…

ACKSHULLY - aerobraking on Mars is a chore. The atmosphere is dense enough to burn you to a crisp, thin enough it won't help you slow down - much. Look at the marvel that is the Skycrane. Not needed for the Moon.

For a dramatic coverage of this exact subject, I highly recommend 'Curiosity's Seven Minutes of Terror' [1] from NASA JPL.

[1] https://www.jpl.nasa.gov/video/details.php?id=1090; or on Youtube: https://www.youtube.com/watch?v=h2I8AoB1xgU

Re: Water Found Deep Inside the Moon

#133

Post by pvaldes »

frandroid wrote: post #87
pc86 wrote: post #77

Earlier quoted context omitted.

Of course you can, it just takes a few orders of magnitude longer.

If the one specialist in your mission dies and it takes 8 years to send a new one, that's not called an effective replacement.

Just send the information and teach a new specialist onlune.

(And don't forget to take an ebook-reader with you in the spaceship with an extensive e-books library).

Re: Water Found Deep Inside the Moon

#134

Post by boznz »

thescriptkiddie wrote: post #131
tambourine_man wrote: post #7

I've always been more excited about a Moon colony than a Mars one. I mean, compared to Mars, the Moon is ridiculously close. Many of the same benefits Musk seeks (backup for Civilization, excitement) for a fraction of the cost. Low gravity and atmosphere on a dome would be more complicated, but again, compared to Mars, it's right there . It would be a more humble and realistic first step, IMO.

I'm all for building Lunar outposts, but colonization is not really practial. Luna simply doesn't have the natural resources to sustain a civilization. Yes there is water in the regolith, but nowhere near as much as on Mars. And critically, Carbon, Nitrogen, Phosphorus, and Sulfur are only present in trace amounts. Nearly all of the elements essential to life will have to be imported, either from Earth, from Mars, or…

"Carbon, Nitrogen, Phosphorus, and Sulfur are only present in trace amounts"

Is this because we havent found them yet, an educated guess or the moon somehow gets rid of these?

Re: Water Found Deep Inside the Moon

#135

Post by codesnik »

drostie wrote: post #108
aaronblohowiak wrote: post #83

Earlier quoted context omitted.

Why not poles?

I'm glad you asked! So there's an important physics reason why the equator is warm and the North and South poles are cold on this planet, and it has to do with how you point a surface. If you ever find yourself in a dark office with a bright desk lamp (or maybe your home office or kid's bedroom might be suitable) you might even try this experiment: take a flat surface, a notepad or steno pad, and hold it up facing th…

why general relativity makes mercury tidal locking wrong? I've heard it's not 1:1, but I don't see any connection

Re: Water Found Deep Inside the Moon

#136

Post by adekok »

quotha wrote: post #53
adekok wrote: post #27

Earlier quoted context omitted.

Mars is effectively a vacuum (for people purposes) anyways, just like the moon. And both are bone-dry, which means lots of static charges when you go outside. The main difference is that Mars has sufficient weather that the dust is roundish, whereas the moon dust is composed of extremely sharp shards. IMHO, if we can't make a go of it on the moon, we have no business going to Mars.

You know there is water on both right?

If only there was an article which talked about water on the moon...

But seriously, since you're going to be unnecessarily pedantic, you're still wrong. Bones (even dry ones on earth) have a MUCH higher percentage of water content than the average location on Mars or the Moon.

Perhaps you could explain why nit-picking is so important? HN isn't a science forum. There's no expectation that people post full scientific justification (with references) for what they say.

It should be about people making polite conversation. Instead, you're missing the point entirely. Which is sad.

Re: Water Found Deep Inside the Moon

#137

Post by WalterBright »

pc86 wrote: post #77
WalterBright wrote: post #70

Earlier quoted context omitted.

You can also rotate the crew on the moon. Can send things to the moon you didn't anticipate. Can send replacement/repair parts. Can't do that for Mars.

Of course you can, it just takes a few orders of magnitude longer.

By then you'll be dead if you actually needed those replacement parts.

Re: Water Found Deep Inside the Moon

#138

Post by rory096 »

jacobush wrote: post #129
rory096 wrote: post #56

Earlier quoted context omitted.

>The 50% figure is from memory, and upon further reflection is probably not quite right, so take it with a grain of salt. You're actually underestimating. Mars has an atmosphere, so spacecraft can use aerobraking to significantly reduce the delta-v required to get there. The moon has no such benefit — propulsion is required all the way to the surface. The advantage of the moon, of course, is that it's not limited to…

ACKSHULLY - aerobraking on Mars is a chore. The atmosphere is dense enough to burn you to a crisp, thin enough it won't help you slow down - much. Look at the marvel that is the Skycrane. Not needed for the Moon.

>thin enough it won't help you slow down - much.

No. It's thin enough you can't land with parachutes alone. It's still enough that Mars Global Surveyor used it to make up a 1,250 m/s delta-v deficit.

Is landing on Mars more complex than a thick atmospheric landing on parachutes or an exoatmospheric landing on propulsion only? Yes. But the atmosphere still saves you a lot of delta-v.

[0] https://mars.jpl.nasa.gov/mgs/sci/aerobrake/SFMech.html

Re: Water Found Deep Inside the Moon

#139

Post by keenerd »

woranl wrote: post #66
tambourine_man wrote: post #7

I've always been more excited about a Moon colony than a Mars one. I mean, compared to Mars, the Moon is ridiculously close. Many of the same benefits Musk seeks (backup for Civilization, excitement) for a fraction of the cost. Low gravity and atmosphere on a dome would be more complicated, but again, compared to Mars, it's right there . It would be a more humble and realistic first step, IMO.

I rather have Civilization backup in Mars. If the Earth goes, the Moon wouldn't be in a very good shape. Just like I wouldn't go hide in the kitchen, while the living room is burning down.

I'm having trouble thinking of catastrophes that could take out both. Well, I can think of a few (bio-weapon, nearby supernova) but they would take out a Mars colony just as easily.

Re: Water Found Deep Inside the Moon

#140

Post by xweb »

ribosometronome wrote: post #88
kbenson wrote: post #84

Earlier quoted context omitted.

> the backup option is only for the wealthy, leaving the rest in a worse state. Like most technology, it flows from the rich to the poor eventually as it becomes cheaper. The important part you omitted is that it leaves the rest in a worse relative state. Their absolute state is no worse, and likely better. Arguing against a backup for civilization (or more appropriately, a backup for the species) because it will be…

Why is humanity's survival important?

Pipe down, Skynet.
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