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#21
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How are the Japanese doing that?
On 6/24/2010 12:26 AM, Mike DiCenso wrote:
No, certainly you weren't. You were just tossing cold water on NASA bashing stroke-fest that was going on there. ;-) It wasn't my intention to bash NASA, but rather to point out that Japan seems to be catching up with our technological capabilities in unmanned spaceflight very quickly indeed. Pat |
#22
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How are the Japanese doing that?
On 6/23/2010 3:03 PM, Brian Thorn wrote:
That's because of SpaceX's very low budget and HTV's very high cost. SpaceX can't afford to do everything on the first flight, JAXA couldn't afford not to. And neither actually docks. They're grabbed by the Station's arm and berthed. Well, after they are berthed to the ISS, people can go aboard them, so that seems to be a distinction with no real meaning, as you could consider the ISS' robotic arm to be part of the docking gear, but attached to the station, not the approaching spacecraft. Pat |
#23
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How are the Japanese doing that?
On Sat, 26 Jun 2010 18:22:09 -0800, Pat Flannery
wrote: Again... that's something NEAR did ten years ago. It wasn't that NEAR landed on 433 Eros...that wasn't in the original plans for the mission, but they pulled it off with aplomb. It's that Hayabusa did things that were in several separate NASA missions combined into one mission. In other words, once America proved the tech concepts would work, Japan combined it all into one mission. Good for them, but it was America that proved it could be done. Now you seem to be saying, 'Look at what Japan's done! They're so much better than America now!'. I say, 'They're getting good, but they still have a lot of catching up to do.' America is already operating an ion engine superior to Hayabusa's on Dawn. I don't consider opening a door on a spacecraft and exposing it to space to gather samples of cometary tail dust or solar wind for return to Earth being actively engaged in sample gathering. Sadly, it isn't up to you to decide what is and is not sample gathering. Everyone's bouncing up and down about Shenzhou and a future threat to the US in space from China. Who is? A few reactionary politicians and talking heads? Big whoop. We don't need another Cold War space race. The first one derailed our long term plans of infrastructure building at an affordable pace in favor of a few big flag-waving events. If China wants to join the party, they're welcome. They are completely missing the boat,IMHO. They're making a race and competition where none exists. So are you. From a economic and scientific point of view, unmanned spacecraft have exerted far more lasting influence on Earth's history than any manned space program ever has (consider the economic, strategic, and sociological impact that weather satellites, reconsats, and comsats have had since Sputnik 1 versus what Apollo accomplished.) Unmanned spacecraft have also been far greater in number than manned spacecraft, so that's not a great surprise. In any case, the success of satellites seems to be a poor reason to cancel manned spaceflight. Large-scale exploration of planetary surfaces will in all likelihood have to wait for humans on the scene. Unmanned rovers are useful for scouting the terrain to identify areas for further study, but they are much too slow and stupid to get the real job of exploration done. To put it another way - as an analogy from the 1930's - everyone is getting hooked on how many battleships a foreign navy has, rather than how many aircraft carriers and submarines it has...although battleships were a obsolete concept once submarines came along, and dive bombers and torpedo planes could take off from ships. I think battleships, per se, weren't obsolete. They still had their place, especially for shore bombardment. Post WW1 battleships were much more strongly built against submarine attack (USS North Carolina survived submarine torpedo attack while the carrier Wasp did not), but all the ones that existed in 1941 were still poorly designed to ward off attack from the air. (So were most shore installations.) Offensive technology was advancing much more quickly than defensive technology. Once defensive technology caught up, with the Iowa-class in the US, battleships were very effective weapons and actually escorted the carriers. The US was in the process of building more carrier-escort battleships, the Montana-class when the war ended. If the Japanese wanted to do it, then a country that could launch something as big and heavy as HTV into orbit could easily launch a multi-manned spacecraft into orbit also, even using crude technology. Unsurprising, since H-II was originally designed to launch HOPE, the H-II Orbiting Plane. See also Ariane V and Hermes. H-II has proven too expensive for anything but government use, and Europe is reportedly planning a smaller single-payload Ariane VI rocket, much closer to the US EELV families, to replace Ariane V. In fact, such a spacecraft would make Shenzhou look small by comparison. Japan is not doing that...and the reason they aren't doing it is that they have realized that unmanned space technology is the wave of the future, Yet Japan has flown seven astronauts on Shuttle and Space Station missions in the last 20 years, their laboratory on the International Space Station is the only one that was not scaled down in the 20 years between go-ahead and launch. Kibo is presently the largest module on ISS and HTV is the second largest unmanned supply ship for the ISS. Japan was among the nations pushing the US to extend ISS to 2020, and is interested in a further extension to 2025-27. That hardly sounds to me like Japan has decided unmanned is the wave of the future. and are going down that road instead, from a cost-versus-benefit point of view. Yet in the last seven years they have launched three unmanned space probes, the three-part Kibo lab for ISS, and the first HTV cargo flight. This sounds to me very much like a space program well balanced between manned and unmanned missions. ...and Hayabusa and their solar sail spacecraft show that they are getting damned good at that damned fast. Hayabusa may not have collected any sample at all, remember. A great learning experience to be sure, but in all likelihood the sample-return mission was a failure. Their solar sail would have been the third of its kind in orbit had launch failures not eaten the first two built by the US. Brian |
#24
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How are the Japanese doing that?
On 6/26/2010 12:05 PM, Brian Thorn wrote:
On Sat, 26 Jun 2010 12:12:17 -0800, Pat wrote: However, the spacecraft did come in contact with the asteroid itself, not once - but twice - to try and recover a sample...and given the low gravity of the asteroid, that's as close as you could get to landing on it. Again... that's something NEAR did ten years ago. It wasn't that NEAR landed on 433 Eros...that wasn't in the original plans for the mission, but they pulled it off with aplomb. It's that Hayabusa did things that were in several separate NASA missions combined into one mission. I don't consider opening a door on a spacecraft and exposing it to space to gather samples of cometary tail dust or solar wind for return to Earth being actively engaged in sample gathering. Everyone's bouncing up and down about Shenzhou and a future threat to the US in space from China. They are completely missing the boat,IMHO. From a economic and scientific point of view, unmanned spacecraft have exerted far more lasting influence on Earth's history than any manned space program ever has (consider the economic, strategic, and sociological impact that weather satellites, reconsats, and comsats have had since Sputnik 1 versus what Apollo accomplished.) To put it another way - as an analogy from the 1930's - everyone is getting hooked on how many battleships a foreign navy has, rather than how many aircraft carriers and submarines it has...although battleships were a obsolete concept once submarines came along, and dive bombers and torpedo planes could take off from ships. If the Japanese wanted to do it, then a country that could launch something as big and heavy as HTV into orbit could easily launch a multi-manned spacecraft into orbit also, even using crude technology. In fact, such a spacecraft would make Shenzhou look small by comparison. Japan is not doing that...and the reason they aren't doing it is that they have realized that unmanned space technology is the wave of the future, and are going down that road instead, from a cost-versus-benefit point of view. ....and Hayabusa and their solar sail spacecraft show that they are getting damned good at that damned fast. Pat |
#25
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How are the Japanese doing that?
On 6/26/2010 5:24 PM, Brian Thorn wrote:
On Sat, 26 Jun 2010 18:22:09 -0800, Pat wrote: Again... that's something NEAR did ten years ago. It wasn't that NEAR landed on 433 Eros...that wasn't in the original plans for the mission, but they pulled it off with aplomb. It's that Hayabusa did things that were in several separate NASA missions combined into one mission. In other words, once America proved the tech concepts would work, Japan combined it all into one mission. Good for them, but it was America that proved it could be done. Now you seem to be saying, 'Look at what Japan's done! They're so much better than America now!' I'm not saying that Japan is superior to the US now; I'm saying that in the field of unmanned spacecraft, they are running neck-and-neck with us, and might well pull ahead in the years to come in the fairly near future. Pat |
#26
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How are the Japanese doing that?
On Sat, 26 Jun 2010 22:19:59 -0800, Pat Flannery
wrote: I'm not saying that Japan is superior to the US now; I'm saying that in the field of unmanned spacecraft, they are running neck-and-neck with us, and might well pull ahead in the years to come in the fairly near future. We must agree to disagree, then. You see Japan gaining on the US, I see them barely holding their own. While Japan flew Hayabusa, the US flew two rovers, a lander and an orbiter to Mars, sent a probe to Pluto, a single ion-powered probe to two of the three largest main belt asteroids, the world's first orbiter to Mercury, and returned samples from a comet. Japan launched a lunar orbiter in recent years, so did the US (and Europe, and China, and India). Japan launched a Venus orbiter earlier this year, the US is preparing to launch a Lunar gravity mapper, an RTG-powered Mars rover and a Jupiter orbiter next year. Brian |
#27
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How are the Japanese doing that?
On Jun 27, 9:39*am, Brian Thorn wrote:
On Sat, 26 Jun 2010 22:19:59 -0800, Pat Flannery wrote: I'm not saying that Japan is superior to the US now; I'm saying that in the field of unmanned spacecraft, they are running neck-and-neck with us, and might well pull ahead in the years to come in the fairly near future. We must agree to disagree, then. You see Japan gaining on the US, I see them barely holding their own. While Japan flew Hayabusa, the US flew two rovers, a lander and an orbiter to Mars, sent a probe to Pluto, a single ion-powered probe to two of the three largest main belt asteroids, the world's first orbiter to Mercury, and returned samples from a comet. Japan launched a lunar orbiter in recent years, so did the US (and Europe, and China, and India). Japan launched a Venus orbiter earlier this year, the US is preparing to launch a Lunar gravity mapper, an RTG-powered Mars rover and a Jupiter orbiter next year. Brian Mission volume as opposed to quality isn't a fair game, much less ignoring their all-inclusive investments, that which Japan isn't putting 10% as much into their missions for obtaining similar or better results. ~ BG |
#28
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How are the Japanese doing that?
On Sat, 03 Jul 2010 21:45:27 -0700, Fred J. McCall
wrote: Who is? A few reactionary politicians and talking heads? Big whoop. We don't need another Cold War space race. The first one derailed our long term plans of infrastructure building at an affordable pace in favor of a few big flag-waving events. You mean it actually got some money spent and technology developed, don't you? The fact that we didn't keep that stuff and use it is something else again, but without the 'race' we wouldn't have had any of it in the first place. Okay, maybe I should have said "Moon Race". The Cold War gave us the space race competition, which is good. But the decision to be on the moon by 1970 wrecked the methodical and sustainable long-term plans that NASA had been developing. And once the moon race was won, we threw all of it away scavenging SkyLab out of what was left. Without the moon race, we probably would have had the entire Saturn family from C-1 to C-4 or C-5, flying in different configurations on different missions both manned and unmanned (Saturn was meant to be the US all-purpose launch vehicle family) and we would have the EOR infrastructure that von Braun originally wanted in place before Saturn V and LOR won the day as the only way to get to the moon in eight years and change. Brian |
#29
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How are the Japanese doing that?
On 7/4/2010 1:31 PM, Brian Thorn wrote:
But the decision to be on the moon by 1970 wrecked the methodical and sustainable long-term plans that NASA had been developing. And once the moon race was won, we threw all of it away scavenging SkyLab out of what was left. Without the moon race, we probably would have had the entire Saturn family from C-1 to C-4 or C-5, flying in different configurations on different missions both manned and unmanned (Saturn was meant to be the US all-purpose launch vehicle family) and we would have the EOR infrastructure that von Braun originally wanted in place before Saturn V and LOR won the day as the only way to get to the moon in eight years and change. I doubt that would have worked; other than a Moon flight there was no real reason to start building space stations (and one must remember that the Colliers WvB "donut" station was to serve military recon and nuclear strike missions as much as building Moon and Mars ships*.) If we had gone that very expensive and slow route, the Soviets would have easily had time to perfect the N-1 and flown a manned Moon mission on a budget long before we were ready to do it.... at which point everyone would ask "Why didn't we do it that way also?" Saturn I and IB were good rockets, if somewhat clunky in basic design concept of the first stage, but notice no other use was found for them once Apollo/Skylab/ASTP had ended, particularly after the Air Force shifted to Titan III and IV. Outside of a manned Moon or Skylab-sized space station launch mission, what exactly would a Saturn V be used for? Or all the other intermediate sized Saturn boosters for that matter? Titan III/Centaur was a pretty clunky thing in its own right (particularly from the solid/hypergolic/cryogenic propellant point of view**) but notice it got used for the major NASA planetary missions rather than a Saturn I derivative. * http://www.spacedaily.com/news/rocketscience-03zzf.html ** If that thing ever blew on the pad during liftoff, it would have been a really fascinating explosion and fire to analyze in slow motion - sort of an entire chemistry class going horribly wrong. :-D Pat |
#30
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How are the Japanese doing that?
On Sun, 04 Jul 2010 20:01:58 -0800, Pat Flannery
wrote: I doubt that would have worked; other than a Moon flight there was no real reason to start building space stations Yet the Russians built eight of them and the United States one. And of course, the moon flight would still have been on the table, it just wouldn't have been part of an enormously expensice race to get the job done by 1970. (and one must remember that the Colliers WvB "donut" station was to serve military recon and nuclear strike missions as much as building Moon and Mars ships*.) Well, that's what Atlas and Titan were built for, too. That doesn't mean we didn't have peaceful missions for them. If we had gone that very expensive and slow route, I don't think it would have been that expensive. I'm talking about a gradual build-up of capability, culminating in an EOR/LOR Apollo-like mission probably after 1975, which is what NASA was working toward in 1960. Certainly not nearly as expensive as Project Apollo, whose mantra was "waste anything but time". the Soviets would have easily had time to perfect the N-1 and flown a manned Moon mission on a budget long before we were ready to do it.... at which point everyone would ask "Why didn't we do it that way also?" I'm talking about if there had never been a moon race, remember. Saturn I and IB were good rockets, if somewhat clunky in basic design concept of the first stage, Yes, but an improved, standard two-tank configuration (instead of multiple Jupiter and Juno tanks) for the first stage would have been a logical upgrade for a second production run, had we ever gotten that far with Saturn. That would give lower manufacturing costs and lower dry mass/higher payload. In fact, that's where S-IC came from, but S-IC grew to be much larger than the S-I/S-IB. In this scenario, S-IB would have been the two-tank replacement for S-I circa 1966 and the much large S-IC first stage would have followed sometime in the 1970s. (Our S-IB was a quick S-I stretch for Saturn IB after the moon race began.) but notice no other use was found for them Except I think Saturns would have replaced Delta, Atlas-Centaur, and Titan III in a non-Moon Race world: one family of launch vehicles instead of three. Basically an EELV program in the 1960s. And having those smaller Saturns in constant production would have made building Saturn C-5 in the 1970s much more affordable. And now with ULA pitching Atlas V Phase II and other growth versions, think that we could have had all that already in one family in the 1960s/1970s with Saturn C-1 through C-5. once Apollo/Skylab/ASTP had ended, particularly after the Air Force shifted to Titan III and IV. The Air Force didn't shift, they never used Saturn at all. They wanted their home-grown Titan all along and didn't care much what the numbers showed Titan vs. Saturn. I think it is painfully obvious that Saturn would have been their better choice: a little more expensive (with that cost difference dropping in the above-described Saturn first stage upgrade) but with enormously better reliability (Saturn had engine-out capability out the wazoo) and enormously greater growth potential with Saturn C-3 and C-4 (both greater than Titan IV in performance) available to them at relatively low development cost and time. Outside of a manned Moon or Skylab-sized space station launch mission, what exactly would a Saturn V be used for? Those would be pretty useful applications right about now, but since the Saturn C-5 is just a high-end version of rockets we already had in production (principally Saturn C-2 and 3, which I suspect would have been the workhorses) it wouldn't be nearly as expensive as Saturn V was in our world. Even then, we may not have needed Saturn C-5 if we had C-3, a Space Station and a nearby propellant depot. Or all the other intermediate sized Saturn boosters for that matter? The same as Delta II through Delta IV-Heavy today. But we'd have had that capabilty circa 1970. Titan III/Centaur was a pretty clunky thing in its own right And Saturns wouldn't have used solids. How many Titans went kablooey thanks to solids? (particularly from the solid/hypergolic/cryogenic propellant point of view**) but notice it got used for the major NASA planetary missions rather than a Saturn I derivative. That's because Saturn was no longer in production. We only had one or two left, and that wasn't enough for both Helioses, both Vikings, and both Voyagers. Titan III was all we had, so someone put a Centaur on top and we made the most of what we had. Brian |
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