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PostPosted: Tue Nov 04, 2014 5:57 am
by The Solar System Scope
You guys know stuff.

PostPosted: Tue Nov 04, 2014 6:43 am
by Northwest Slobovia
The Solar System Scope wrote:You guys know stuff.

Uh, probably. What are you talking about?

PostPosted: Tue Nov 04, 2014 7:11 am
by The Solar System Scope
You type all that stuff and understand it like pros.

PostPosted: Tue Nov 04, 2014 7:44 am
by Northwest Slobovia
The Solar System Scope wrote:You type all that stuff and understand it like pros.

I've been interested in space stuff for most of my life, and I'm much older than typical NS posters. Lotta experience reading up on it... and one of my relatives worked for NASA, and he used to bring me all this neat stuff (books mostly, but he got me tours of some of their facilities). These days, I also have a friendly neighborhood astronomer, and we talk science, mission profiles, and money. He really knows the details of space probes and what they can do (and for how much!) so he's an invaluable resource. (He's also one of the many people who influences what gets built and for how much, so he has a lot of inside knowledge.)

Also, back then there was a Usenet, I spent a lot of time reading sci.space.*, and many of the people who posted there were actual rocket scientists, and one woman was an actual NASA test pilot. They had a lot of useful things about how spaceflight works, what it costs, and why we do certain things and not others (some are good reasons, some aren't... but there are reasons). They were pros, and they'd occasionally post really detailed analyses of new spacecraft and such, which was incredible reading.

PostPosted: Tue Nov 04, 2014 10:57 am
by Monkeykind
Northwest Slobovia wrote:
The Solar System Scope wrote:You type all that stuff and understand it like pros.

I've been interested in space stuff for most of my life, and I'm much older than typical NS posters. Lotta experience reading up on it... and one of my relatives worked for NASA, and he used to bring me all this neat stuff (books mostly, but he got me tours of some of their facilities). These days, I also have a friendly neighborhood astronomer, and we talk science, mission profiles, and money. He really knows the details of space probes and what they can do (and for how much!) so he's an invaluable resource. (He's also one of the many people who influences what gets built and for how much, so he has a lot of inside knowledge.)

Also, back then there was a Usenet, I spent a lot of time reading sci.space.*, and many of the people who posted there were actual rocket scientists, and one woman was an actual NASA test pilot. They had a lot of useful things about how spaceflight works, what it costs, and why we do certain things and not others (some are good reasons, some aren't... but there are reasons). They were pros, and they'd occasionally post really detailed analyses of new spacecraft and such, which was incredible reading.

I can see that, founded 8 years ago.

PostPosted: Tue Nov 04, 2014 11:12 am
by Northwest Slobovia
Monkeykind wrote:
Northwest Slobovia wrote:I've been interested in space stuff for most of my life, and I'm much older than typical NS posters. Lotta experience reading up on it... and one of my relatives worked for NASA, and he used to bring me all this neat stuff (books mostly, but he got me tours of some of their facilities). These days, I also have a friendly neighborhood astronomer, and we talk science, mission profiles, and money. He really knows the details of space probes and what they can do (and for how much!) so he's an invaluable resource. (He's also one of the many people who influences what gets built and for how much, so he has a lot of inside knowledge.)

Also, back then there was a Usenet, I spent a lot of time reading sci.space.*, and many of the people who posted there were actual rocket scientists, and one woman was an actual NASA test pilot. They had a lot of useful things about how spaceflight works, what it costs, and why we do certain things and not others (some are good reasons, some aren't... but there are reasons). They were pros, and they'd occasionally post really detailed analyses of new spacecraft and such, which was incredible reading.

I can see that, founded 8 years ago.

Oh, even older than that: while I don't publish my age here, I do say that I've been blissfully married for over 20 years. :hug: And let me just say we were way older than the age of consent when we got hitched, so even older still. ;)

But enough about me. More actual astronomy: a couple of meteors were spotted over the US yesterday. Anybody see them?

PostPosted: Tue Nov 04, 2014 11:28 am
by Monkeykind
Northwest Slobovia wrote:
Monkeykind wrote:I can see that, founded 8 years ago.

Oh, even older than that: while I don't publish my age here, I do say that I've been blissfully married for over 20 years. :hug: And let me just say we were way older than the age of consent when we got hitched, so even older still. ;)

But enough about me. More actual astronomy: a couple of meteors were spotted over the US yesterday. Anybody see them?

That's...old.

PostPosted: Tue Nov 04, 2014 11:41 am
by Brickistan
Northwest Slobovia wrote:
Brickistan wrote:
a) In this case, I was thinking more about practical knowledge of surviving in ultra-hostile environments. For purely scientific endeavors, I would mainly agree with you - that can be handled by robots.

I think I understand your emphasis on hostile environment survival, but I'm not sure that that's going to get many people into space. If we reason from what we know on Earth, the more hostile the environment, the more expensive it is to keep somebody alive there. Since space seems very hostile, the implied cost would argue for very few people in space.

Immoren's point above about building domed cities on a planetary surface seems like a reasonable approach, assuming there's an economic reason for there to be a city on the planet in the first place. The Martian surface is pretty harsh, but it's easier to survive there than on a space station or on the surface of an airless moon or asteroid.

Brickistan wrote:b) NASA has, unfortunately, been starved of resources for a very long time now. Indeed, had it been given just a fraction of what the US military industrial complex gets, we could very well have had manned missions to Mars by now.

Both issues, really, are down to a lack of will on the part of politicians. Sadly, these days there just isn't much interest in doing basic science and exploration.

That's another point I'm going to have to start my answer to with "Well...". :)

Sure, NASA's budget is "only" $20G/yr, compared to the military's ~$650G/yr budget, but that's a lot of research! And NSF is providing a steady billion dollars a year for astronomy.* That's pretty amazing, I think: it means every taxpayer is, on average, kicking in $10/yr to do nothing more than buy telescopes. That's pure basic research. (*: Personal communication from my friendly neighborhood astronomer.)

As to Mars missions, one of the things we learned from Curiosity is that the interplanetary radiation environment is a lot harsher than we thought, even during periods of "quiet sun". The same is true for the Martian surface. I have a bad feeling that if we'd sent Mars missions in the late 70's like NASA wanted, we would have killed a lot of guys because we didn't understand how hard the problem is. :?


I see where you're coming from.

Do keep in mind though, that we need to go through space to get to another planet. If we can't survive the journey to Mars, then we can't settle there either.

Also, don't forget that it's way cheaper to leave orbit than to achieve orbit. That's why space stations are so vital. Without those to build and maintain spaceships, we're probably not going to get anywhere.

As for the Mars Mission, I agree that it would most likely have been a one-way trip. In fact, I suspect that the first we send, even if it won't be for another fifty years or so, will still be a one-way ticked. Without facilities on Mars, bringing enough fuel to not only land safely but also achieve escape velocity again will most likely be too much.

PostPosted: Tue Nov 04, 2014 11:45 am
by Immoren
Brickistan wrote:
Also, don't forget that it's way cheaper to leave orbit than to achieve orbit. That's why space stations are so vital. Without those to build and maintain spaceships, we're probably not going to get anywhere.
.



Obviously in the future, majority of humanity shall live on asteroid colonies and space station colonies, and only ones living on planetary surfaces are those whose work forces them to live there and those with strange/backwards ideologies. *nods*

PostPosted: Tue Nov 04, 2014 11:51 am
by Monkeykind
Brickistan wrote:
Northwest Slobovia wrote:I think I understand your emphasis on hostile environment survival, but I'm not sure that that's going to get many people into space. If we reason from what we know on Earth, the more hostile the environment, the more expensive it is to keep somebody alive there. Since space seems very hostile, the implied cost would argue for very few people in space.

Immoren's point above about building domed cities on a planetary surface seems like a reasonable approach, assuming there's an economic reason for there to be a city on the planet in the first place. The Martian surface is pretty harsh, but it's easier to survive there than on a space station or on the surface of an airless moon or asteroid.


That's another point I'm going to have to start my answer to with "Well...". :)

Sure, NASA's budget is "only" $20G/yr, compared to the military's ~$650G/yr budget, but that's a lot of research! And NSF is providing a steady billion dollars a year for astronomy.* That's pretty amazing, I think: it means every taxpayer is, on average, kicking in $10/yr to do nothing more than buy telescopes. That's pure basic research. (*: Personal communication from my friendly neighborhood astronomer.)

As to Mars missions, one of the things we learned from Curiosity is that the interplanetary radiation environment is a lot harsher than we thought, even during periods of "quiet sun". The same is true for the Martian surface. I have a bad feeling that if we'd sent Mars missions in the late 70's like NASA wanted, we would have killed a lot of guys because we didn't understand how hard the problem is. :?


I see where you're coming from.

Do keep in mind though, that we need to go through space to get to another planet. If we can't survive the journey to Mars, then we can't settle there either.

Also, don't forget that it's way cheaper to leave orbit than to achieve orbit. That's why space stations are so vital. Without those to build and maintain spaceships, we're probably not going to get anywhere.

As for the Mars Mission, I agree that it would most likely have been a one-way trip. In fact, I suspect that the first we send, even if it won't be for another fifty years or so, will still be a one-way ticked. Without facilities on Mars, bringing enough fuel to not only land safely but also achieve escape velocity again will most likely be too much.

It'll be a one'way ticket for a few decades.

PostPosted: Tue Nov 04, 2014 7:10 pm
by Nord Amour
I thought this to be somewhat interesting.

http://www.sciencedaily.com/releases/20 ... 121034.htm

PostPosted: Tue Nov 04, 2014 7:32 pm
by Northwest Slobovia
Nord Amour wrote:I thought this to be somewhat interesting.

http://www.sciencedaily.com/releases/20 ... 121034.htm

Yeah, planet formation in a triple star system is pretty odd. I'll have to see if I can get a copy of the paper, it looks interesting.

Also interesting is that they got such good results from ground-based IR telescopes. I mean, sure, IR window 'scopes are capable of some things, but we don't punt IR scopes into orbit for nothing.

PostPosted: Tue Nov 04, 2014 8:27 pm
by Northwest Slobovia
Brickistan wrote:
Northwest Slobovia wrote:I think I understand your emphasis on hostile environment survival, but I'm not sure that that's going to get many people into space. If we reason from what we know on Earth, the more hostile the environment, the more expensive it is to keep somebody alive there. Since space seems very hostile, the implied cost would argue for very few people in space.

Immoren's point above about building domed cities on a planetary surface seems like a reasonable approach, assuming there's an economic reason for there to be a city on the planet in the first place. The Martian surface is pretty harsh, but it's easier to survive there than on a space station or on the surface of an airless moon or asteroid.


That's another point I'm going to have to start my answer to with "Well...". :)

Sure, NASA's budget is "only" $20G/yr, compared to the military's ~$650G/yr budget, but that's a lot of research! And NSF is providing a steady billion dollars a year for astronomy.* That's pretty amazing, I think: it means every taxpayer is, on average, kicking in $10/yr to do nothing more than buy telescopes. That's pure basic research. (*: Personal communication from my friendly neighborhood astronomer.)

As to Mars missions, one of the things we learned from Curiosity is that the interplanetary radiation environment is a lot harsher than we thought, even during periods of "quiet sun". The same is true for the Martian surface. I have a bad feeling that if we'd sent Mars missions in the late 70's like NASA wanted, we would have killed a lot of guys because we didn't understand how hard the problem is. :?


I see where you're coming from.

Do keep in mind though, that we need to go through space to get to another planet. If we can't survive the journey to Mars, then we can't settle there either.

Sure, it's just a lot harder to do than we thought.

[Your reply rearranged for easier comment.]

Brickistan wrote:As for the Mars Mission, I agree that it would most likely have been a one-way trip. In fact, I suspect that the first we send, even if it won't be for another fifty years or so, will still be a one-way ticked. Without facilities on Mars, bringing enough fuel to not only land safely but also achieve escape velocity again will most likely be too much.

Well, based on what we know now, a Hohmann transfer orbit voyage with 1970's ideas of sufficient shielding may not have gotten the crew to Mars alive. Beyond the background radiation problem, we seem to have underestimated the energy in the big solar flares, and one of those could kill the crew or wreck the ship's electronics. Hand-flying Apollo 13 was hard enough, and the crew was on a free-return orbit; getting home from Mars with slide rules is a lot harder.

But other than the radiation shielding problem, two way trips aren't that hard. A few options:

1) Apollo option: build a really big rocket. :)

2) Apollo backup option: launch two or more rockets for every manned landing; the extra rockets are fuel tankers or are putting different parts of the ship into orbit (see below).

2a) Go to Mars from someplace else (space station or moon base). It's a special case of 2) once you consider that 2) requires a parking orbit somewhere, and this is "just" adding permanent facilities to that parking orbit.

3) Make fuel on Mars: requires bringing a big power supply, but the math for electrolyzing the atmosphere (in to carbon monoxide and oxygen, IIRC) works just fine. That's a crappy fuel-oxidizer combination, but the return vehicle is small and so is the delta-V, so the miserable mass fraction isn't so bad.

4) Better engines: a higher Isp (specific impulse; spaceship fuel economy, more or less) will get a ship of the same size to Mars faster. We already have solar/ion engines, and they seem to work fine. Fission/ion would give give us more thrust, since we could throw more power at the problem. Fission rocket engines are plenty possible, but we've never gone beyond static tests for those.

There are probably other options I'm not thinking of; those are just what came to mind.

Brickistan wrote:Also, don't forget that it's way cheaper to leave orbit than to achieve orbit. That's why space stations are so vital. Without those to build and maintain spaceships, we're probably not going to get anywhere.

Oh, that's got a bunch of interesting assumptions! Sure, there's less delta-V required, but "cheaper" in dollars? That's far from obvious for space stations.

So, back to 2) from above. Consider going to Mars with three launches. Launch one sends a reusable Mars lander into a martian parking orbit, where it waits for a crew. Launch two puts the Earth-to-Mars (E2M) ship into a LEO parking orbit. Launch three sends a reusable ship (like the Shuttle or Delta Clipper) to the E2M ship, where it transfers the crew and supplies, and then hangs out in LEO.

Every ship is reusable: both atmospheric stages and the E2M ship. While those ships are waiting between missions, they can do typical space stuff: the Mars lander might have its own scientific instruments to observe Mars, for example, and the E2M ship could be used as a temporary space station for experiments that require in-person tending. So why build a station?

It's really not clear that building ships in orbit is cost-effective. It may make more sense to launch prefab modules that dock under ground control. Likewise for repair: it may be cheaper to just bring modules home in some big reusable ship.

I'm not saying space stations are a money pit, just that's it not obvious that they're the way to go, even if we did have a busy space schedule ahead of us. Sure 2001 looks good, but Kubrick didn't have to pay for an actual space station. :)

PostPosted: Wed Nov 05, 2014 1:30 am
by Risottia
Northwest Slobovia wrote:I'm kinda amused at the way you dismiss what corporations did as "building components". I mean, NASA did all the hard work: saying "hey, we need a rocket kinda like this" is really the difficult step in any space mission. The designing, building, and testing of said rocket is trivial. I mean, it's not rocket scien... Oh. :P

I'm amused at the way you dismiss what NASA did as "we need a rocked like this", considering how they designed the whole missions, the specifications, and how the components should link between themselves, plus training the space and land crew, controlling the components' spefications, and whatnot. I mean, it's not rocket scien... Oh. :p

And yes, a stage is a component of a multi-stage vector, fyi.

But seriously, I'm not sure what you mean by "mission entrusted".

It's not rocket science again. "Mission entrusted" means "who is taking the responsibility for the whole project and for the whole set of GO/NO GO".

I mean, it looks like there was a problem with the first stage engine of Orbital's rocket.

Which was Orbital's responsibility.

Risottia wrote:Then again, the Challenger exploded because of a NASA error.

Time to blame the evil capitalist pig-dogs. :p

When you have nothing intelligent to say, it's time to build stupid strawmen.

PostPosted: Wed Nov 05, 2014 1:34 am
by Risottia
Northwest Slobovia wrote:3) Make fuel on Mars: requires bringing a big power supply, but the math for electrolyzing the atmosphere (in to carbon monoxide and oxygen, IIRC) works just fine. That's a crappy fuel-oxidizer combination, but the return vehicle is small and so is the delta-V, so the miserable mass fraction isn't so bad.


Overall, I'd say that this is the best option, also for a first mission. An automated fuel plant - with very few moving parts - could be dropped on Mars years before the crewed mission, so to have fuel enough for the time the crew has to return home.

PostPosted: Wed Nov 05, 2014 1:39 am
by Risottia
Btw, Rosetta and Philae explained for kids.

http://www.esa.int/spaceinvideos/Videos ... et_landing

PostPosted: Wed Nov 05, 2014 11:12 am
by Monkeykind
Risottia wrote:Btw, Rosetta and Philae explained for kids.

http://www.esa.int/spaceinvideos/Videos ... et_landing

Rosseta the bathtime toy.

PostPosted: Wed Nov 05, 2014 12:01 pm
by Northwest Slobovia
Risottia wrote:
Northwest Slobovia wrote:I'm kinda amused at the way you dismiss what corporations did as "building components". I mean, NASA did all the hard work: saying "hey, we need a rocket kinda like this" is really the difficult step in any space mission. The designing, building, and testing of said rocket is trivial. I mean, it's not rocket scien... Oh. :P

I'm amused at the way you dismiss what NASA did as "we need a rocked like this", considering how they designed the whole missions, the specifications, and how the components should link between themselves, plus training the space and land crew, controlling the components' spefications, and whatnot. I mean, it's not rocket scien... Oh. :p

Not as far as I know. I've been trying to find detailed descriptions of who did what, and I'm simply getting more confused. For example, Boeing says,
The largest production model of the Saturn family of rockets, the Saturn V was designed under the direction of Wernher von Braun at the Marshall Space Flight Center in Huntsville, Ala., with Boeing, North American Aviation, Douglas Aircraft and IBM as the lead contractors.

Which agrees with you: von Braun, working at Marshall, led the design, which certainly sounds like NASA did the heavy thinking.

But later on the same page, it says:

Boeing responsibility to NASA included detailed design, fabrication and assembly of the S-IC in New Orleans and testing of the first stage at the former Mississippi Test Facility (renamed the National Space Technology Laboratories) at nearby Bay St. Louis. Subsequent assignments included systems engineering, vehicle integration and mission support for the entire Saturn V vehicle at Huntsville, Ala., spacecraft engineering and assessment at the Kennedy Space Center, and technical staff support to the Apollo program office at NASA headquarters, Washington, D.C.


Which is more like what I thought: NASA produced high-level requirements, and got aerospace companies to figure out all the details and do the work.

Von Braun's chapter in NASA's official history of Apollo (Apollo Expeditions to the Moon) isn't helping much either. He clearly distinguishes between "developing" and "producing" things, but then talks about "development" going on at both Marshall and the private companies. And then he adds stuff like the Instrument Unit being a Marshall Labs development produced by IBM, but based on an earlier launch-vehicle computer developed by IBM, which sounds more like multi-generational design with a lot of give-and-take betwen government and private industry. (The chapter's too long to type in.)

If you've got better sources, please let me know, 'cause I'm not sure who did what any more. :? :unsure:

Risottia wrote:
Time to blame the evil capitalist pig-dogs. :p

When you have nothing intelligent to say, it's time to build stupid strawmen.

Teasing, not a serious counter-arguement.

But more seriously, if you're gonna argue that NASA does so well and bears total responsibility for all previous manned missions, then they have a lot of blood on their hands. Not only the crews of Apollo 1, Challenger, and Columbia, but everybody who died in training building up US manned spaceflight capability. Which, um, isn't a great record.

PostPosted: Wed Nov 05, 2014 2:19 pm
by Monkeykind
Northwest Slobovia wrote:
Risottia wrote:I'm amused at the way you dismiss what NASA did as "we need a rocked like this", considering how they designed the whole missions, the specifications, and how the components should link between themselves, plus training the space and land crew, controlling the components' spefications, and whatnot. I mean, it's not rocket scien... Oh. :p

Not as far as I know. I've been trying to find detailed descriptions of who did what, and I'm simply getting more confused. For example, Boeing says,
The largest production model of the Saturn family of rockets, the Saturn V was designed under the direction of Wernher von Braun at the Marshall Space Flight Center in Huntsville, Ala., with Boeing, North American Aviation, Douglas Aircraft and IBM as the lead contractors.

Which agrees with you: von Braun, working at Marshall, led the design, which certainly sounds like NASA did the heavy thinking.

But later on the same page, it says:

Boeing responsibility to NASA included detailed design, fabrication and assembly of the S-IC in New Orleans and testing of the first stage at the former Mississippi Test Facility (renamed the National Space Technology Laboratories) at nearby Bay St. Louis. Subsequent assignments included systems engineering, vehicle integration and mission support for the entire Saturn V vehicle at Huntsville, Ala., spacecraft engineering and assessment at the Kennedy Space Center, and technical staff support to the Apollo program office at NASA headquarters, Washington, D.C.


Which is more like what I thought: NASA produced high-level requirements, and got aerospace companies to figure out all the details and do the work.

Von Braun's chapter in NASA's official history of Apollo (Apollo Expeditions to the Moon) isn't helping much either. He clearly distinguishes between "developing" and "producing" things, but then talks about "development" going on at both Marshall and the private companies. And then he adds stuff like the Instrument Unit being a Marshall Labs development produced by IBM, but based on an earlier launch-vehicle computer developed by IBM, which sounds more like multi-generational design with a lot of give-and-take betwen government and private industry. (The chapter's too long to type in.)

If you've got better sources, please let me know, 'cause I'm not sure who did what any more. :? :unsure:

Risottia wrote:When you have nothing intelligent to say, it's time to build stupid strawmen.

Teasing, not a serious counter-arguement.

But more seriously, if you're gonna argue that NASA does so well and bears total responsibility for all previous manned missions, then they have a lot of blood on their hands. Not only the crews of Apollo 1, Challenger, and Columbia, but everybody who died in training building up US manned spaceflight capability. Which, um, isn't a great record.

http://www.google.co.uk/url?sa=t&rct=j& ... 7474,d.cWc
8 Astronoaut fatality incidents, 12 non-astronaut fatality incidents. Total of 20 different incidents.

PostPosted: Tue Nov 11, 2014 12:34 pm
by Risottia
http://blogs.esa.int/rosetta/2014/11/11 ... -on-track/

Rosetta is GO for the Philae separation. In 4.30 hourse we'll have a GO/NO GO for the separation of Philae. The signal confirming the actual separation is expected on Earth at 09.03 GMT (10.03 CET) and the descent will last about 7 hours.

Jump like a boss, Philae! 8)

PostPosted: Tue Nov 11, 2014 1:05 pm
by Monkeykind
Risottia wrote:http://blogs.esa.int/rosetta/2014/11/11/gonogo-1-rosetta-is-on-track/

Rosetta is GO for the Philae separation. In 4.30 hourse we'll have a GO/NO GO for the separation of Philae. The signal confirming the actual separation is expected on Earth at 09.03 GMT (10.03 CET) and the descent will last about 7 hours.

Jump like a boss, Philae! 8)

I've been counting down since the eighth!
http://futuretimeline.net/21stcentury/2014.htm#rosetta

PostPosted: Wed Nov 12, 2014 12:14 am
by Brickistan
So it seems that the final go has just been given and Rosetta is now slowing down to achieve a lower orbit for delivery. Going to be interesting to follow this...

PostPosted: Wed Nov 12, 2014 12:20 am
by Oceans Haven
@-@ this thread is awesome....TAG. ill be reading this in my free time xD

PostPosted: Wed Nov 12, 2014 8:41 am
by The Solar System Scope

PostPosted: Wed Nov 12, 2014 9:32 am
by Monkeykind
The Solar System Scope wrote:Keep track of Philae!

THE COMET HAS LANDED PEOPLE!