Actually, the reason for the asteroid mission instead of the lunar one is simple. It will require essentially the same type of spaceship that is required to get to Mars
uhh since when do asteroids have an a atmosphere? You *MIGHT* pull that argument off with a comet.
It takes roughly 6 months to get *to* Mars. That requires a vehicle that is safe from radiation, has a life support system rated for that length of time, GNC able to handle that length of time and distance, and a lot of other factors. Those are the *exact* same requirements for a vehicle for an asteroid mission. It is not the 3-5 day requirement to get from Earth to the Moon. That tasks nothing in terms of long duration flight. Landing *on* Mars requires an additional R&D step - a step where the Moon provides essentially no real advantage over LEO operations or Earth based operations..
That tempeture you are going on about is in the average -66F range. The atmosphere is quite toxic to humans (95.3%) plus nitrogen (2.7%), argon (1.6%) and traces of oxygen (0.15%) and water (0.03%). It is also about 1% of the pressure.
And the Moon cycles between several hundred below zero to several hundred above. But, only in direct light. It is a vacuum outside that and has weird heat transfer characteristics. You can take the Martian atmosphere and pump it through a number of already built and prototyped systems and generate fuel and oxygen. It is a sustainable resource and technology that is already done. To build a lunar base, you would also have to pump a lot of R&D dollars to support lunar operations. That is lost dollars as far as a Mars mission is concerned. It provides zero R&D leverage onto further development. Not a problem if the Moon is your destination, but if you are doing the Moon as a prototype for Mars, then you have a glaring problem in that this is a solution that is already developed and any additional dollars is a waste from a Mars mission perspective.
The weight thing you are going on about is also bunk. As an asteroid is going to have even LESS gravity than the moon.
Which is why you do the hab design on Earth where it is very cheap to do that sort of development and is a lot safer. You test each segment of the Mars mission in terms of where it is the most cost effective.
You sir are trying to justify something because of your political bent not because it actually makes sense...
Every single technical gain for Mars that has been used to justify Lunar development is cheaper by a combination of Earth/LEO/and asteroid development. Mars is just a stalking horse for people, who want a Lunar Base. If you want to go to the Moon, that has to be the goal. Not as a critical step in another development path. It diverts resources from both the end path and the intermediate step.
The thing is, all of the stuff you are pointing out represents huge expenditures as well as R&D. All Lunar specific. All stuff that would have to be developed specifically to meet Lunar needs. Which is fine - provided that your goal is going to the Moon. But, every single penny sent on developing lunar mining is a penny not being spent on developing Mars tech. You're setting up parallel development paths and multibillion dollar (or even trillion dollar) bases.
Capacitors still have less energy density than batteries. And, they would still have to be transported to the Moon. And, handwaving "ores locally" as no technology has ever been developed to mine and process said ores. (They have already built prototype fuel factories for Mars and tested them). Shoot.. they still have not even directly observed ice on the Moon, much less developed a way to process it. (All of the claims of water on the Moon are based on a guess that the absorption of certain wavelengths of radar correspond to Hydrogen, then they *assume* a certain amount of potential water if said Hydrogen might be bound in water molecules as opposed to being hydrated minerals or other type of presence).
There are a lot of tradeoffs, but the big one is this: spend money on making a Mars Base feasible or making a Lunar Base feasible.
Well.. you could start by building a LEO test model. A tethered capsule can be rotated until it simulates exactly 1/3rd G. Take anything you just asked about and ask if the Moon is the best place for any of that testing.
6 months of hard vacuum can be managed in LEO also. You can even test 1/3rd gravity by using a tether system.
6 months on Earth's South Pole is about the same as 6 months on the Moon's South Pole when you are looking at going to Mars.
If the stated goal is *Mars* exploration, then sidetracked very expensive development should be discouraged. If the goal is the Moon, go there. If it is Mars, develop in that direction. They do not overlap that much in terms of technology and all the other technological development "advantages" that people point out all lose when you compare them to other alternatives. "6 months hard vacuum".. LEO. Lower gravity.. well, in LEO, you can even simulate the exact weight you need. 6 months transit time.. shoot an asteroid mission has to be developed to that exact spec as opposed to a lunar model of a week duration.
Do the math on the weight of the batteries required to hold enough energy to last a lunar base for 14 days, then get back to me.
Also.. that little bit of atmosphere turns out to be a huge difference. Look at any of the in-situ experiments done on creating fuel from the atmosphere and you have tons of fuel being cranked out with essentially very little required power. You have a medium to fly through (dirigibles and blimps will work using hydrogen gas on Mars). You have completely different heating issues. Mars is not similar to the Moon in terms of how the environment affects the mission or technologies.
Transit to the Moon: roughly 3 days. Transit to Mars: roughly 6 months.
6 months? Shoot.. they do that now at the South Pole. You can test *any* 6 month duration anywhere just by not going there for 6 months. And still be 20 minutes away in case of a real emergency. They have already built and started testing the analogs for Martian bases here. Pretty basic stuff. Build out a hab module. Put some people in it. Let them live there for gradually longer periods of time. Take the lessons learned, incorporate them into the next version. It does not even remotely require the Moon to test if someone can live in a hab for 6 months.
Take your argument one step further.. If you are 5-6 days away from Earth or 20 minutes away from a fully staffed support facility, which would you chose?
The long range comm and navigation portions are more analogous if designed for an asteroid mission than a lunar one. A lunar mission has a fixed point and set trajectory. An asteroid mission would need to be able to navigate and handle comm millions of miles away from Earth.
Weird, they don't even address any of the technical of economic objections to the Moon vs Mars mission. The article misses a lot of key points.
1) There is very little technical overlap in designs between a lunar and martian based program. The Moon has no atmosphere. That means no atmospheric braking. A lander landing on the Moon is radically different than one landing on Mars since the lunar one has to use only rockets to slow its descent. The Martian one can use rockets and parachutes as well as glide. Also, the lack of an atmosphere means that the Moon can not as easily provide oxygen or fuel as Mars, where those products can be pulled directly from the atmosphere. The Moon requires regolith mining to obtain any materials.
2) The transfer vehicle to the Moon is going to be able to complete the trip within 120 hours, or 240 hours if you have to do a return. That is easily within the range of not needing to recycle. You can just load up with consumables and then replenish at either end of the trip. The Martian vehicle will have to have some pretty hefty recycling technology.
3) The day/night cycle on the Moon is vastly longer than that of Mars. Mars is pretty close to that of Earth. Solar power is not even remotely practical on the Moon. (Except in the polar regions where it s theorized that would be possible to find spots where you have continual daylight). If you want to go somewhere other than the poles on the Moon for any duration, you are looking at needing a new generation of nuclear power. Which would also be useful on Mars, but there is a tradeoff there in terms of mass and other factors.)
4) I am back to "There is no atmosphere on the Moon" because it keeps impacting multiple areas. One of the problems that needs to be solved is HVAC type issues. Keeping things warm or cold. The Moon has no atmosphere, hence no convective heat transfer. All heat transfer is radiative or conductive. That necessitates a completely different thermodynamic paradigm than would be possible on Mars.
5) In terms of Human factors, the Moon is 1/6th gravity and Mars is 1/3th. That means items on Mars weighs twice as much as that on the Moon. The lunar space suits can not be worn on Mars as they are too heavy. New ones need to be designed. (We're also back to "The Moon has no atmosphere". Space suits need to be able to maintain a steady temperature inside. Since a lunar space suit is essentially a thermos when you consider it is in vacuum, all you have to worry about it shedding excess heat. On Mars, you are essentially enveloped by a fluid - the atmosphere - which has a temperature and can carry away excess heat.)
Actually, the reason for the asteroid mission instead of the lunar one is simple. It will require essentially the same type of spaceship that is required to get to Mars. The lunar base only has about 20% overlap with Mars technologies and - honestly - for those 20%, Earth is as good an analog as the Moon. When you develop a technology to go to the Moon, that is what you are developing. You are not developing one for Mars.
Essentially, you get the Moon and Mars for only twice the amount as getting the Moon or Mars.
Only the lowest casings of the SRB's have any sort of load bearing members. And.. more importantly, the ET takes almost all of the atmospheric loading on the Shuttle. The SRB's are located behind the bow shock of the ET. They are never exposed directly to the full brunt of the atmosphere. The max-Q for the SRB's are several orders of magnitude lower than they would be on a stand-alone launch vehicle.
The foam comes off of the external tank because it is a *hydrogen* cryogenic system. Hydrogen is cold enough that it liquifies or freezes any gas that comes in contact with it. Water vapor freezes into the foam making the foam rigid. As the air liquifies, it forms a vacuum drawing in yet more air. The liquified air them comes into contact with the adhesives that connect the foam to the tank. Not very many adhesives can handle that level of cold. If you look at the Shuttle, you will note that the hydrogen tanks are mounted above the LOX tanks due to stability issues with the different densities of the materials. What impacts the Shuttle is from the Hydrogen cryo systems. Using Kerosene or any number of other fuels would eliminate the foam issue. Actually.. now that I think about it.. Saturn V also had its insulation shedding like anything during launch and it did not matter as the design of the vehicle was such that debris fell aft. The foam only hits the Shuttle Orbiter as the Shuttle is mounted in the shock wave behind the external tank.
LOX, on the other hand, is not exceptionally cold and is easier to keep away from the air. It doesn't really matter much whether it sheds foam or insulation in the type of system described here as the crew capsule would be mounted fore of the fuel and oxygen tanks.
LOX is routinely handled by thousands of industrial facilities in the US alone. Its properties are well known and it has been used safely for over a century.
Liquid boosters have been used safely on dozens of rocket types. They have been used safely to launch crewed capsules. Liquid rocket engines are commercially available. (In fact, every single crewed American vehicle has had liquid fuels as their main source of energy. The SRB's on the Shuttle are booster assist and the only Gemini to fly on a solid was an unmanned test capsule).
What we are seeing here is a departure from decades of development. Solids have been considered unsafe for manned flight for decades as they are not able to be throttled in flight. Once lit, they burn to exhaustion. They have uneven burn characteristics due to uneven mixing of the propellants. No solid casing has ever been put in a load of this magnitude. (The SRB's on the Shuttle never carried the full weight of the shuttle and they were axially loaded as opposed to have the load directly along the case). There is no engine shutdown in an SRB.
Arguing that liquids would take a lot of development to get right is a bit misleading as it is just as much a statement to be made for SRB's.
The whole Shuttle-derived stuff is crap. These are essentially new engines along with a new booster design and they should have had a design competition and weigh the relative merits of various design proposals. This was a fiat decision made by Griffin when he came into office. There was no technical justification. No weighing of options. Even the sizing of the Orion is extremely questionable.
Clause 2: The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it.
In Lincoln's case. The Southern States were officially recognized as being in a state of rebellion. That clearly invokes the clause mentioned above. And, if you look at it from a different angle and consider the CSA as a separate nation, then the latter part of the clause was valid as the CSA did, in fact, invade portions of territory that the US considered to be its territory. (Tennessee actually voted *against* seccession in a general election).
What Gonzoles says is that there is no right of Habeas Corpus *granted* and the President can not revoke something that has not been granted. ie, you have no rights, except those explicitly *granted* by the Constitution.
Well.. I, for one, never really bought into the myth that kids today are unmotivated. It is good to see someone with ambition and drive. I am, like many others, sadly noting the use he put his money to.
Dude, its not Swiss bank accounts or the Cayman Islands. Its Vegas Baby.. Alcohol, women, drugs, gambling... In my day, we did not give a damn about the future as we knew we could always steal more. They can take your possessions away, but never your memories. In my day, we created companies that sold nothing and listed money invested by venture capitalists as "sales" and gave ourselves huge bonuses.. This plan would have really worked, if you have followed the 1990's model and not actually provided any services...
On the serious side tho.. Doesn't this raise some fundamental questions about VOIP security? If I am reading this correctly, they did not hack the VOIP software itself, but a computer on which they resided, then ran the software normally. That opens a lot of systems worldwide to this sort of scheme.
That is a sun synchronous orbit. Fairly useful if you are taking photos. Every time you pass over part of your orbit, the shadows will be at the same angle as your previous pass. Much easier to calculate form and height when you always know the relative angle to the sun.
It is also a useful orbit in that it covers the entire planet, including the poles. If you are interested in items, such as global warming and relative ice-pack, you need to use this sort of orbit.
Not sure if any of the sats in this are configured as Amsats, but this high an inclination could even allow people living in the far north and far south some communcation relay capability.
They used to crash the upper stages of the Saturn 5 to gain scientific data from the Moon. Learned a lot that way.
Hard to say if this will work though. The theoretical plume size has a lot of unknowns involved. To date, they have never directly observed water on the Moon, but have only identified a certain amount of hydrogen, which would correspond to a certain amount of water, if that hydrogen was bound in water molecules. If the hydrogen is hydrated minerals, that plume will be much, much smaller than projected.
Let's get real here. They had already been put in an indefinate hold over the foam issue before Katrina. And, a 6 month delay for that was just as fatal for any shuttle flight to Hubble. They won't even be able to finish ISS in the remaining timeframe. Now, NASA can point at something outside its control and say "This is why Hubble was scrapped".
The odds of a Hubble mission before Katrina: 0.01% The odds of a Hubble mission after Katrina: 0.005%
I suspect that this was more a victim of Fox thinking they had a clinched demographic and slot. Since X-Files was successful and in that slot, other shows along the same line should also be successful. But, X-Files was moved into that slot bringing its audience with it. None of the other shows them have wedged in there have really had much of a draw on their own.
Also, there is the matter of episode cost. Science fiction is relatively expensive compared to "reality" television and even shows like "The OC". F/X shots every show. Costuming for Firefly was interesting as they did not do the "all-people-of-this-culture-wear-identical-clothes " that a number of scifi shows has done.
I suspect that there were a lot of fights that year about "reality" vs scripted shows inside Fox.
I doubt it had anything to do with any political message inside the show itself. It was strictly a dollar issue and lack of patience.
I am leaning towards very stupid. No vehicle in the stated CEV performance range has ever weighed more than 10k. The Apollo CM was only 5k. A Service module for LEO would be only another 5k, or so - even with a cargo hold.
When you see an engineering statement "this vehicle in this range will weigh X amount" and then research the issue and find the no other vehicle in history operating in that performance range has been in that weight range, then there is something else driving the engineering.
I was leery of CEV when they specified EELV in the specs as there are other launch vehicles available in the correct launch mass range that could have been used. It should have been an open spec with the design teams making proposals based upon a) cost b) safety and c) performance. Design to a spec. I am even more leery now that they have gone to the trouble of putting "shuttle-derived" back on the board with the SRB's as their choice of derivation. Those were designed for lateral loads, not vertical loads. They are not throttable. They are not startable/stopable and nearly every single failure mode is "loss of crew".
I do have more hope in things like SpaceX. If they can deliver their vehicle at the cost/performance they seem to be leaning towards, then there are a number of companies who can build an additional manned component. It is a much lower barrier to entry. Multi-billion projects? You're right. No one out there to do it. But, a series of $10-$100 million projects aimed at leveraging off existing hardware is doable.
Of course, no male dominated program at NASA has ever failed. Mars Observer Mission was a stellar example of quality, for example. As was any number of other missions.. I guess women so completely dominated Shuttle development that no one could ever recover from their core flaws..
The fact of the matter is that the Discovery Missions have been systemically flawed since they started adding elements to them. Exactly what was the success rate the past couple launch windows? 30%? Comes from taking a small budget, cramming as much stuff in as possible and leaving no budget for testing. There is a systemic flaw in NASA. It is called "Incapability to build to a budget". They keep adding features to each successive layer of a prgram to do *more* each mission rather than do the same amount, but with different objectives, because they have the *same* budget.
You're specific example is, by far, the most technically challenging task in the last round of flights. Slamming impactors into an unknown surface at orbital insertion velocities with a period of about 18 months from proposal to hardware with *zero* testing allowed for in the budget (time and equipment).. What did you expect? At least they *hit* the planet instead of mistaking how close it will flyby..
That is not a male/female issue. That is just plain bad engineering and it happens in male dominated programs as much as anywhere else.
NASA prizes were pushed through by a female. You sure you want to advocate this?
The truth of the matter is that NASA has managed a grand total of *one* piece of man rated flying hardware in the past 20 years and it took 15 years between Reagan proposing the space station in 1984 until they actually flew it. If NASA had a better track record the 20 years prior to the time you are complaining about, you might have had a point, but really? You're just blowing smoke. NASA flew a space mission once every 6 months, or so, and had variable success rate long before the hiring practices you are complaining about were implemented.
It is a bit more problematic than that. If you look closer at the specifics of what he wants to do, he's assuming certain technical decisions. He is expecting CEV to weigh in over 50k pounds. He is putting shuttle derived tech into the mix.
When someone hires engineering staff based upon preconcieved technical solutions, that is just politics wearing a different mask for the day.
Well, the problem with satire and sarcasm these days is that it really is hard to find someone who is able to take satire outside the bounds of basic fanboy flaming a series they did not understand...
Make a case they didn't mean it. You're also going to have to make a case that all the anonymous cowards are just goofing.. And, this is/. You've never seen someone make a serious idiotic post before?
Slashdot Mirror
Actually, the reason for the asteroid mission instead of the lunar one is simple. It will require essentially the same type of spaceship that is required to get to Mars
uhh since when do asteroids have an a atmosphere? You *MIGHT* pull that argument off with a comet.
It takes roughly 6 months to get *to* Mars. That requires a vehicle that is safe from radiation, has a life support system rated for that length of time, GNC able to handle that length of time and distance, and a lot of other factors. Those are the *exact* same requirements for a vehicle for an asteroid mission. It is not the 3-5 day requirement to get from Earth to the Moon. That tasks nothing in terms of long duration flight. Landing *on* Mars requires an additional R&D step - a step where the Moon provides essentially no real advantage over LEO operations or Earth based operations..
That tempeture you are going on about is in the average -66F range. The atmosphere is quite toxic to humans (95.3%) plus nitrogen (2.7%), argon (1.6%) and traces of oxygen (0.15%) and water (0.03%). It is also about 1% of the pressure.
And the Moon cycles between several hundred below zero to several hundred above. But, only in direct light. It is a vacuum outside that and has weird heat transfer characteristics. You can take the Martian atmosphere and pump it through a number of already built and prototyped systems and generate fuel and oxygen. It is a sustainable resource and technology that is already done. To build a lunar base, you would also have to pump a lot of R&D dollars to support lunar operations. That is lost dollars as far as a Mars mission is concerned. It provides zero R&D leverage onto further development. Not a problem if the Moon is your destination, but if you are doing the Moon as a prototype for Mars, then you have a glaring problem in that this is a solution that is already developed and any additional dollars is a waste from a Mars mission perspective.
The weight thing you are going on about is also bunk. As an asteroid is going to have even LESS gravity than the moon.
Which is why you do the hab design on Earth where it is very cheap to do that sort of development and is a lot safer. You test each segment of the Mars mission in terms of where it is the most cost effective.
You sir are trying to justify something because of your political bent not because it actually makes sense...
Every single technical gain for Mars that has been used to justify Lunar development is cheaper by a combination of Earth/LEO/and asteroid development. Mars is just a stalking horse for people, who want a Lunar Base. If you want to go to the Moon, that has to be the goal. Not as a critical step in another development path. It diverts resources from both the end path and the intermediate step.
The thing is, all of the stuff you are pointing out represents huge expenditures as well as R&D. All Lunar specific. All stuff that would have to be developed specifically to meet Lunar needs. Which is fine - provided that your goal is going to the Moon. But, every single penny sent on developing lunar mining is a penny not being spent on developing Mars tech. You're setting up parallel development paths and multibillion dollar (or even trillion dollar) bases.
Capacitors still have less energy density than batteries. And, they would still have to be transported to the Moon. And, handwaving "ores locally" as no technology has ever been developed to mine and process said ores. (They have already built prototype fuel factories for Mars and tested them). Shoot.. they still have not even directly observed ice on the Moon, much less developed a way to process it. (All of the claims of water on the Moon are based on a guess that the absorption of certain wavelengths of radar correspond to Hydrogen, then they *assume* a certain amount of potential water if said Hydrogen might be bound in water molecules as opposed to being hydrated minerals or other type of presence).
There are a lot of tradeoffs, but the big one is this: spend money on making a Mars Base feasible or making a Lunar Base feasible.
Well.. you could start by building a LEO test model. A tethered capsule can be rotated until it simulates exactly 1/3rd G. Take anything you just asked about and ask if the Moon is the best place for any of that testing.
6 months of hard vacuum can be managed in LEO also. You can even test 1/3rd gravity by using a tether system.
6 months on Earth's South Pole is about the same as 6 months on the Moon's South Pole when you are looking at going to Mars.
If the stated goal is *Mars* exploration, then sidetracked very expensive development should be discouraged. If the goal is the Moon, go there. If it is Mars, develop in that direction. They do not overlap that much in terms of technology and all the other technological development "advantages" that people point out all lose when you compare them to other alternatives. "6 months hard vacuum".. LEO. Lower gravity.. well, in LEO, you can even simulate the exact weight you need. 6 months transit time.. shoot an asteroid mission has to be developed to that exact spec as opposed to a lunar model of a week duration.
Do the math on the weight of the batteries required to hold enough energy to last a lunar base for 14 days, then get back to me.
Also.. that little bit of atmosphere turns out to be a huge difference. Look at any of the in-situ experiments done on creating fuel from the atmosphere and you have tons of fuel being cranked out with essentially very little required power. You have a medium to fly through (dirigibles and blimps will work using hydrogen gas on Mars). You have completely different heating issues. Mars is not similar to the Moon in terms of how the environment affects the mission or technologies.
Transit to the Moon: roughly 3 days. Transit to Mars: roughly 6 months.
6 months? Shoot.. they do that now at the South Pole. You can test *any* 6 month duration anywhere just by not going there for 6 months. And still be 20 minutes away in case of a real emergency. They have already built and started testing the analogs for Martian bases here. Pretty basic stuff. Build out a hab module. Put some people in it. Let them live there for gradually longer periods of time. Take the lessons learned, incorporate them into the next version. It does not even remotely require the Moon to test if someone can live in a hab for 6 months.
Take your argument one step further.. If you are 5-6 days away from Earth or 20 minutes away from a fully staffed support facility, which would you chose?
The long range comm and navigation portions are more analogous if designed for an asteroid mission than a lunar one. A lunar mission has a fixed point and set trajectory. An asteroid mission would need to be able to navigate and handle comm millions of miles away from Earth.
Weird, they don't even address any of the technical of economic objections to the Moon vs Mars mission. The article misses a lot of key points.
1) There is very little technical overlap in designs between a lunar and martian based program. The Moon has no atmosphere. That means no atmospheric braking. A lander landing on the Moon is radically different than one landing on Mars since the lunar one has to use only rockets to slow its descent. The Martian one can use rockets and parachutes as well as glide. Also, the lack of an atmosphere means that the Moon can not as easily provide oxygen or fuel as Mars, where those products can be pulled directly from the atmosphere. The Moon requires regolith mining to obtain any materials.
2) The transfer vehicle to the Moon is going to be able to complete the trip within 120 hours, or 240 hours if you have to do a return. That is easily within the range of not needing to recycle. You can just load up with consumables and then replenish at either end of the trip. The Martian vehicle will have to have some pretty hefty recycling technology.
3) The day/night cycle on the Moon is vastly longer than that of Mars. Mars is pretty close to that of Earth. Solar power is not even remotely practical on the Moon. (Except in the polar regions where it s theorized that would be possible to find spots where you have continual daylight). If you want to go somewhere other than the poles on the Moon for any duration, you are looking at needing a new generation of nuclear power. Which would also be useful on Mars, but there is a tradeoff there in terms of mass and other factors.)
4) I am back to "There is no atmosphere on the Moon" because it keeps impacting multiple areas. One of the problems that needs to be solved is HVAC type issues. Keeping things warm or cold. The Moon has no atmosphere, hence no convective heat transfer. All heat transfer is radiative or conductive. That necessitates a completely different thermodynamic paradigm than would be possible on Mars.
5) In terms of Human factors, the Moon is 1/6th gravity and Mars is 1/3th. That means items on Mars weighs twice as much as that on the Moon. The lunar space suits can not be worn on Mars as they are too heavy. New ones need to be designed. (We're also back to "The Moon has no atmosphere". Space suits need to be able to maintain a steady temperature inside. Since a lunar space suit is essentially a thermos when you consider it is in vacuum, all you have to worry about it shedding excess heat. On Mars, you are essentially enveloped by a fluid - the atmosphere - which has a temperature and can carry away excess heat.)
Actually, the reason for the asteroid mission instead of the lunar one is simple. It will require essentially the same type of spaceship that is required to get to Mars. The lunar base only has about 20% overlap with Mars technologies and - honestly - for those 20%, Earth is as good an analog as the Moon. When you develop a technology to go to the Moon, that is what you are developing. You are not developing one for Mars.
Essentially, you get the Moon and Mars for only twice the amount as getting the Moon or Mars.
Only the lowest casings of the SRB's have any sort of load bearing members. And.. more importantly, the ET takes almost all of the atmospheric loading on the Shuttle. The SRB's are located behind the bow shock of the ET. They are never exposed directly to the full brunt of the atmosphere. The max-Q for the SRB's are several orders of magnitude lower than they would be on a stand-alone launch vehicle.
The foam comes off of the external tank because it is a *hydrogen* cryogenic system. Hydrogen is cold enough that it liquifies or freezes any gas that comes in contact with it. Water vapor freezes into the foam making the foam rigid. As the air liquifies, it forms a vacuum drawing in yet more air. The liquified air them comes into contact with the adhesives that connect the foam to the tank. Not very many adhesives can handle that level of cold. If you look at the Shuttle, you will note that the hydrogen tanks are mounted above the LOX tanks due to stability issues with the different densities of the materials. What impacts the Shuttle is from the Hydrogen cryo systems. Using Kerosene or any number of other fuels would eliminate the foam issue. Actually.. now that I think about it.. Saturn V also had its insulation shedding like anything during launch and it did not matter as the design of the vehicle was such that debris fell aft. The foam only hits the Shuttle Orbiter as the Shuttle is mounted in the shock wave behind the external tank.
LOX, on the other hand, is not exceptionally cold and is easier to keep away from the air. It doesn't really matter much whether it sheds foam or insulation in the type of system described here as the crew capsule would be mounted fore of the fuel and oxygen tanks.
LOX is routinely handled by thousands of industrial facilities in the US alone. Its properties are well known and it has been used safely for over a century.
Liquid boosters have been used safely on dozens of rocket types. They have been used safely to launch crewed capsules. Liquid rocket engines are commercially available. (In fact, every single crewed American vehicle has had liquid fuels as their main source of energy. The SRB's on the Shuttle are booster assist and the only Gemini to fly on a solid was an unmanned test capsule).
What we are seeing here is a departure from decades of development. Solids have been considered unsafe for manned flight for decades as they are not able to be throttled in flight. Once lit, they burn to exhaustion. They have uneven burn characteristics due to uneven mixing of the propellants. No solid casing has ever been put in a load of this magnitude. (The SRB's on the Shuttle never carried the full weight of the shuttle and they were axially loaded as opposed to have the load directly along the case). There is no engine shutdown in an SRB.
Arguing that liquids would take a lot of development to get right is a bit misleading as it is just as much a statement to be made for SRB's.
The whole Shuttle-derived stuff is crap. These are essentially new engines along with a new booster design and they should have had a design competition and weigh the relative merits of various design proposals. This was a fiat decision made by Griffin when he came into office. There was no technical justification. No weighing of options. Even the sizing of the Orion is extremely questionable.
Clause 2: The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it.
In Lincoln's case. The Southern States were officially recognized as being in a state of rebellion. That clearly invokes the clause mentioned above. And, if you look at it from a different angle and consider the CSA as a separate nation, then the latter part of the clause was valid as the CSA did, in fact, invade portions of territory that the US considered to be its territory. (Tennessee actually voted *against* seccession in a general election).
What Gonzoles says is that there is no right of Habeas Corpus *granted* and the President can not revoke something that has not been granted. ie, you have no rights, except those explicitly *granted* by the Constitution.
Unless I miss my guess, Russia hasn't trailed in number of launches per year in probably 30 years. This is roughly their normal percentage.
Well.. I, for one, never really bought into the myth that kids today are unmotivated. It is good to see someone with ambition and drive. I am, like many others, sadly noting the use he put his money to.
Dude, its not Swiss bank accounts or the Cayman Islands. Its Vegas Baby.. Alcohol, women, drugs, gambling... In my day, we did not give a damn about the future as we knew we could always steal more. They can take your possessions away, but never your memories. In my day, we created companies that sold nothing and listed money invested by venture capitalists as "sales" and gave ourselves huge bonuses.. This plan would have really worked, if you have followed the 1990's model and not actually provided any services...
On the serious side tho.. Doesn't this raise some fundamental questions about VOIP security? If I am reading this correctly, they did not hack the VOIP software itself, but a computer on which they resided, then ran the software normally. That opens a lot of systems worldwide to this sort of scheme.
That is a sun synchronous orbit. Fairly useful if you are taking photos. Every time you pass over part of your orbit, the shadows will be at the same angle as your previous pass. Much easier to calculate form and height when you always know the relative angle to the sun.
It is also a useful orbit in that it covers the entire planet, including the poles. If you are interested in items, such as global warming and relative ice-pack, you need to use this sort of orbit.
Not sure if any of the sats in this are configured as Amsats, but this high an inclination could even allow people living in the far north and far south some communcation relay capability.
They used to crash the upper stages of the Saturn 5 to gain scientific data from the Moon. Learned a lot that way.
Hard to say if this will work though. The theoretical plume size has a lot of unknowns involved. To date, they have never directly observed water on the Moon, but have only identified a certain amount of hydrogen, which would correspond to a certain amount of water, if that hydrogen was bound in water molecules. If the hydrogen is hydrated minerals, that plume will be much, much smaller than projected.
eh? You just *think* that that is his right leg...
Let's get real here. They had already been put in an indefinate hold over the foam issue before Katrina. And, a 6 month delay for that was just as fatal for any shuttle flight to Hubble. They won't even be able to finish ISS in the remaining timeframe. Now, NASA can point at something outside its control and say "This is why Hubble was scrapped".
The odds of a Hubble mission before Katrina: 0.01%
The odds of a Hubble mission after Katrina: 0.005%
Yeah.. you're right.. it is half as likely now..
I always knew there was something sinister about this creature
I suspect that this was more a victim of Fox thinking they had a clinched demographic and slot. Since X-Files was successful and in that slot, other shows along the same line should also be successful. But, X-Files was moved into that slot bringing its audience with it. None of the other shows them have wedged in there have really had much of a draw on their own.
s " that a number of scifi shows has done.
Also, there is the matter of episode cost. Science fiction is relatively expensive compared to "reality" television and even shows like "The OC". F/X shots every show. Costuming for Firefly was interesting as they did not do the "all-people-of-this-culture-wear-identical-clothe
I suspect that there were a lot of fights that year about "reality" vs scripted shows inside Fox.
I doubt it had anything to do with any political message inside the show itself. It was strictly a dollar issue and lack of patience.
I am leaning towards very stupid. No vehicle in the stated CEV performance range has ever weighed more than 10k. The Apollo CM was only 5k. A Service module for LEO would be only another 5k, or so - even with a cargo hold.
When you see an engineering statement "this vehicle in this range will weigh X amount" and then research the issue and find the no other vehicle in history operating in that performance range has been in that weight range, then there is something else driving the engineering.
I was leery of CEV when they specified EELV in the specs as there are other launch vehicles available in the correct launch mass range that could have been used. It should have been an open spec with the design teams making proposals based upon a) cost b) safety and c) performance. Design to a spec. I am even more leery now that they have gone to the trouble of putting "shuttle-derived" back on the board with the SRB's as their choice of derivation. Those were designed for lateral loads, not vertical loads. They are not throttable. They are not startable/stopable and nearly every single failure mode is "loss of crew".
I do have more hope in things like SpaceX. If they can deliver their vehicle at the cost/performance they seem to be leaning towards, then there are a number of companies who can build an additional manned component. It is a much lower barrier to entry. Multi-billion projects? You're right. No one out there to do it. But, a series of $10-$100 million projects aimed at leveraging off existing hardware is doable.
Of course, no male dominated program at NASA has ever failed. Mars Observer Mission was a stellar example of quality, for example. As was any number of other missions.. I guess women so completely dominated Shuttle development that no one could ever recover from their core flaws..
The fact of the matter is that the Discovery Missions have been systemically flawed since they started adding elements to them. Exactly what was the success rate the past couple launch windows? 30%? Comes from taking a small budget, cramming as much stuff in as possible and leaving no budget for testing. There is a systemic flaw in NASA. It is called "Incapability to build to a budget". They keep adding features to each successive layer of a prgram to do *more* each mission rather than do the same amount, but with different objectives, because they have the *same* budget.
You're specific example is, by far, the most technically challenging task in the last round of flights. Slamming impactors into an unknown surface at orbital insertion velocities with a period of about 18 months from proposal to hardware with *zero* testing allowed for in the budget (time and equipment).. What did you expect? At least they *hit* the planet instead of mistaking how close it will flyby..
That is not a male/female issue. That is just plain bad engineering and it happens in male dominated programs as much as anywhere else.
NASA prizes were pushed through by a female. You sure you want to advocate this?
The truth of the matter is that NASA has managed a grand total of *one* piece of man rated flying hardware in the past 20 years and it took 15 years between Reagan proposing the space station in 1984 until they actually flew it. If NASA had a better track record the 20 years prior to the time you are complaining about, you might have had a point, but really? You're just blowing smoke. NASA flew a space mission once every 6 months, or so, and had variable success rate long before the hiring practices you are complaining about were implemented.
It is a bit more problematic than that. If you look closer at the specifics of what he wants to do, he's assuming certain technical decisions. He is expecting CEV to weigh in over 50k pounds. He is putting shuttle derived tech into the mix.
When someone hires engineering staff based upon preconcieved technical solutions, that is just politics wearing a different mask for the day.
It probably is closer to $8. Just showing what a specific size fanbase will manage, if it has any loyalty..
Well, the problem with satire and sarcasm these days is that it really is hard to find someone who is able to take satire outside the bounds of basic fanboy flaming a series they did not understand...
/. You've never seen someone make a serious idiotic post before?
Make a case they didn't mean it. You're also going to have to make a case that all the anonymous cowards are just goofing.. And, this is
Which means:
http://www.imdb.com/title/tt0379786/business
"budget $40,000,000 (estimated)"
Throw in an average ticket price of $5 and the thing has posted $35 million over its production costs....
Just off its established fanbase.