And the Earth is not flat. It's approximately spherical! And it goes around the Sun, not vice versa. I don't care what the Pope says about it: Galileo Galilei was right and the Bible is wrong!
Are you talking about the same things as the rest of us? From reading this I'm pretty sure you don't know what you're talking about.
Pope Benedict XVI never said Galileo was wrong. He didn't even endorse the sentence against him. What he did, while he was still Cardinal Ratzinger, was quote some (agnostic, by the way) philosopher's opinion of the matter in relation to the revisionism that was occuring in the 18th century: "The church at the time of Galileo was much more faithful to reason than Galileo himself, and also took into consideration the ethical and social consequences of Galileo's doctrine. Its verdict against Gaileo was rational and just, and revisionism can be legitimized solely for motives of political opportunism."
You can not read this fairly without noting that Cardinal Ratzinger himself refers to this opinion as drastic. He favors the quote by Bloch saying, "Christianity has the right to remain faithful to its method of preserving the earth in relation to human dignity, and to order the world with regard to what will happen and what has happened in the world." Meaning basically that although physically the earth revolves around the sun, it's still the center of human activity.
This speech was two years before Pope John Paul II publicly apoligized for the way the church responded to Galileo. Cardinal Ratzinger never himself said the church was right in handling the Galileo affair, and he most certainly never supported geocentrism. However, it seems there's plenty of people who are happy to falaciously believe that claim, sadly including this supposedly well-educated Professor Cini.
You also don't appear to know what historically happened. The board of Inquisitors told Galileo and others not to publicly advocate heliocentrism. He was still permitted to discuss it hypothetically. Galileo had been vocally advocating it and creating quite a stir at the time, because a lot of sticks in the mud flat-out rejected it because they were ignorant, knee-jerk reactionists. He graciously agreed.
When Galileo's friend, Pope Urban VIII succeeded to the papacy, he returned to the subject. Urban actually requested he write a book on it, but again, not to press the arguments directly. However, he didn't hold very well to that condition, and actually used quotes from Urban in presenting Artitotelian viewpoint that ended up sounding rather mocking, although probably inadvertantly.
This public embarrassment unfortunately alienated the Pope, and the sticks-in-the-mud won out, forcing him to publicly recant the theory of heliocentrism, banning the book, and placing him under house arrest for several years.
Ironically, Copernicus had been teaching about heliocentrism 100 years earlier, and his theories were well-received at the time by several popes and innumerable academics. It took that long for the knee jerkers to gain support higher up and find a fittingly controversial victim.
Am I the only one who sees a self-sustaining materials and manufacturing infrastructure on the moon as being worth any cost today? Without it, we'll never realize our sci-fi dreams of colonizing off the planet.
This is true. I agree with this part. However, everytime the topic of ISRU comes up, I see plenty of armchair engineers talking lightly about applying it from the get-go at very, very advanced levels, and it's clear they haven't given any real thought to what it takes to achieve the sort of results they're talking about. One of the posters above, for example, dismisses building a pressure vessel for a habitat as fairly elementary. That first of all neglects the point about structural mass actually being a minority of the payload needs for a moon base, and secondly shows an ingorance of the large and specialized tooling needed to build such components here on earth. How much can that infrastructure actually be shrunk down, made lightweight, or made multipurpose by simply sacrificing productivity?
As I said, I agree if we're going to live in space truly long term, we need to learn to use the resources out there. Once we reach the trade surplus point, we'll have reached that dream of the lunar-industrial age. But it seems like everyone is assuming with a little clever engineering we can do that right now. That's not so. It will take a herculean amount of engineering, testing, re-engineering, failing, succeeding, and taking baby steps to get there.
That's why the first resource utilization will be simple things. Once you've established a baseline competancy, it's easier to add on to it than to do the whole thing all at once. It also leaves you in a better and less expensive position to react to problems or unanticipated supply or demand changes.
On the point about sending unmanned missions first. That is actually part of the plan. NASA decided last year they should identify several targets on the moon of scientific interest and send short "sortie" mission similar to the Apollo program there. At the same time, they would also pick a site for a permanent base and land equipment there in advance of a crew. Right now it looks like two missions to send power, basic supplies, and a basic habitat. Then short manned mission to get everything set up. This would be followed by a longer missions with stuff like ISRU equipment, a pressurized rover for long exploration missions, and additional living/science facilities.
Unfortunately, such things are not as easy in real life as they are in star trek. Have you seen even small processing operations here on earth? Even when you know exactly what you're working with, it has a high percentage of what you want, and the wheat is easily separated from the chaff, it takes a large piece of rather expensive machinery to accomplish it. Wheat and chaff case in point: a typical John Deere combine weighs about 12 tons. All it does it cut wheat, seperate the kernels from the heads, and dump the straw out the back. And it needs gas and air in sufficient quantities to produce about 200 hp to operate. Obviously that's a high volume farm implement, not an optimized space tool, but I stand by the basic point.
Think about what that extensive mineral utilization entails. You're limited by what's up there. The lunar regolith is mostly aluminum oxide, silica, and some calcium, with trace amounts of various gasses like hydrogen and helium. Suppose then you want fiberglass. That's an easy one. You suspend the regolith in a liquid and separate the silica from the alumina based on density. Then you melt the silica and blow it out of a fine nozzle to form strands. Unless you can figure out how to do it in a vaccuum, however, which is plausible, you need a gas to blow it, either brought from earth or boiled out of the regolith.
That right there is five primary subsystems:
1.) Power
2.) Regolith collector
3.) Silica separator
4.) Furnace and fiber machine
5.) Gas storage and/or production.
But fiberglass is all but useless without epoxy, and making fiberglass parts is a messy, complicated job here on earth. You'd be crazy to stake the success of your lunar base on the ability for a self deploying robot to produce useful and quality controlled parts on the moon. Not to mention, all you've got at that point is structural parts, which are only a fraction of the mass of supplies you need.
You could look at the same needs for producing aluminum. It gets really interesting when you start looking at the mass of equipment needed to produce sheet aluminum out of cast ingots. The raw aluminum itself is very energy intenstive to produce, requiring 7.5 kW-hours of electricity per pound to reduce from alumina in high volume smelters.
And I'm not even going to get started on what it takes to make complex shapes like a pressurized habitat or a seal for an airlock.
All of this is why NASA is looking at landing all the needed supplies on the moon and practicing the techniques with human involvement from the start. The first supplies produced will probably be oxygen (which can be electrolytically separated from the silica, alumina, or small amounts of ice present on the moon), and bricks for radiation protection and insulation sintered from the raw regolith.
Start simple. As you show you can make useful items from simple processes, then you add complexity.
Mine was on the Vic-20, the Commodore-64's immediate predecessor. The first was a simple Basic counting game that I think my mom wrote as part of a programming tutorial. I'm guessing I was about three years old at the time.
My first commercial game was probably Tooth Invaders. You were a toothbrush, running around on a set of 2-D teeth, removing plague. Germs would wander around depositing plague and could kill you. If enough plague accumulated, you'd get a cavity and lose. Graphics quality put Strong Bad's "Duck Pond" to shame. After that it was Mole Attack, Moon Base, and the best game available at the time: Choplifter.
After we got a 286, I spent quite a bit of time on the first edition of Microsoft Flight Simulator, flying a 172 out of Midway, amusing myself sometimes by flying into the Hancock building.
Aww...the memories. I should go find an emulator and ROM's for all these.
You're quite right on the basic principle: Corn stalks (aka stover) can be used as the ethanol feedstock. However, my understanding is that the plans are to ramp up ethanol production beyond what corn stover alone could produce, and there is some limited other use of the corn stocks for feed and mulch.
It sounds like the reason the waste isn't currently used is merely that no one has built the plants. The initial round of plants being built rely heavily on waste material like this.
By the way, here is the original wikipedia article I referred to. It covers the production methods and refers to several research studies that have been conducted investigating the feasibility of ethanol as a supplemental fuel. It does not appear to be viable as a complete replacement for gasoline, however.
http://en.wikipedia.org/wiki/Cellulosic_ethanol
Re-reading it, I believe I've understated the known scalability of cellulosic processes, as there are several commercial demonstration plants in operation or under construction producing millions of gallons per year. As noted, however, they currently cost more up front than corn ethanol plants. Also, there are claims that I haven't yet cared to look into that the corn industry has successfully lobbied to maintain an advantage for the development of corn-based ethanol production. A little short-sighted, I would think, since rather than planting more crops, the farmers could be getting greater return on existing crops by selling more of their waste.
This has been circulating around the intarwebs for a few days now, so it spurred me to do some background reading already.
Corn has higher amounts of the simpler sugars that bacteria need to work on to produce the ethanol. Switchgrass and other cellulosic feedstocks, which are largely equivalent in feasbility in general terms, have those sugars bound up in...you guessed it...cellulose. Because of this it requires much more processing prior to fermentation. There are several ways to do this with varying costs and efficiencies, but at the very least is technically viable.
However, this pre-processing and the fact that large-scale cellulosic ethanol production is a new technology means the initial costs are higher. According to Wikipedia (with original sources referenced), corn ethanol plants cost about $1-3 per gallon of annual capacity to construct. The first round of large scale cellulosic ethanol plants now under construction are billed about $7 per gallon of annual capacity. Production costs are expected to run about $2.25 per gallon initially, or about $125 per barrel of oil energy equivalent.
However, as the method is proven, that cost is expected to come down. About $350 million of cost is also being funded by the federal government under the new energy plan. Also, the cost of the feedstock for cellulosic ethanol production is much lower, as it can use switchgrass as mentioned in the summary, corn stover, wood chips, or just about anything else containing plant matter, where as the corn method requires corn (duh), and thus competes with food production.
Of course, the article makes the energy-return benefit over corn ethanol obvious. Elsewhere it has been estimated that cellulosic ethanol production could account for 30% of our transportation energy needs in a couple decades. Obviously far short of weaning us off foreign oil, but a start nonetheless. However, an added benefit of using grasses like switchgrass is the fields don't have to be replanted every year, reducing soil depletion and erosion.
We've learned with near certainty that there were large amounts of liquid water on Mars in the past. This shows that Mars was almost certainly more like Earth in its past, may still maintain some suitability for human life, and brightens hopes of finding extra-solar, earth-like planets.
We've studied the geological history of Mars in detail that was utterly impossible via any other means short of landing actual people there. This hints at the similarities and differences between Mars and Earth and may help us better understand how our own planet evolved and operates.
We've studied the Martian atmosphere in reasonable detail and gathered more information on its climate. If we ever find it beneficial to try living there (or decide to do so regardless of benefit), this information will be vital.
We've developed and tested a new set of scientific tools, robotic components, autonomous navigation techniques, etc. Several of these were new to the mission.
We've produced thousands of stunning images of an alien surface. That alone is certainly worth as much as public art. Nothing inherently makes the Statue of Liberty, for example, more valuable than Mars Rovers...or, at the risk of sparking the public-vs-private money debate, those big screen TV's everyone has to have.
And we've helped inspire further generations of youth to study science and math.
NASA actually is quite forthcoming with information about their discoveries, but the general public often cares little for more than the most basic details, and thus the private news media usually only give passing mention to NASA press releases. If you're genuinely curious to learn more about the rovers' work, browse through old press releases on the website: http://marsrovers.jpl.nasa.gov/home/index.html
The most successful of recent NASA projects have been the most thoughtful and focused, not the highest spenders.
While I agree some strict budget control measures are long called for, I'm afraid the above quote isn't quite true. I'm having a lot of trouble thinking of missions that fit your description: successful, focused, not big spenders. Mars Pathfinder probably, although it wasn't necessarily a really focused mission. It was primarily a technology demonstrator. Stardust, Deep Impact, Mars Odyssey, and Mars Global Surveyor all get nods. But on the other hand:
The Mars Exploration Rovers were about 30% over budget and Opportunity nearly got cut from the manifest several times. Their goals at time of launch were also somewhat ambiguous.
The Hubble was originally proposed as a $400 million dollar project. As of 1986, that had grown to $1.2 billion. By launch it had cost over $2.5 billion, not counting the servicing mission for the defective mirror. Total costs are around $5 billion now.
Cassini was roughly on budget and so far has been quite successful, but it was a huge spender. That single mission cost $3.2 billion.
Galileo was likewise successful at Jupiter, was not without problems and experienced growth from $270 million to $1.4 billion.
The Mars Climate Orbiter and Mars Polar Lander were both very well focused missions developed from the "better, faster, cheaper" mantra. Both were spectacular failures.
The issue here is that NASA comes up with some really nifty missions, but underestimates the cost and sometimes mis-manages programs, as you've described. However, some of the missions are just too good to let go of, so they continuously eat the cost overruns and delays because they really want the science a particular mission is going to allow. Other times they've invested so much in a mission they don't want to throw all the investment out, and they pay the extra just to make sure they get something out of it. I may have said the MER's didn't have real clear objectives, but NASA knew they had versatile machines and dug up the extra money because they knew they could work with whatever they found on the surface.
The James Webb Space Telescope is an even better, and more current example. It's had features removed or downsized several times, but has still suffered explosive cost growth and delays. However, every time it gets reviewed, the science guys say they absolutely must have this mission and other things get cut to pay for it.
We have most definitely tested nuclear weapons on, above, and below the ground. The Trinity test was only about 100 meters above the ground and kicked up a fair amount of dust, but it definitely did not spread globally.
The impact, should we be fortunate enough to witness one, will no doubt kick up a huge amount of dust over an area of a couple dozen square miles. However, the total energy of this impact is likely to pale compared to even a modestly sized dust storm, and as the cloud spreads out over thousands of square miles, the opacity will drop quickly.
NOAA says that a fully developed hurricane releases 10 megatons of energy every 20 minutes. The storm Opportunity and Spirit endured a few months ago was lower intensity but far, far larger in scale than a hurricane, and it lasted for weeks. Opportunity, fortunately, had a stiff breeze later blow a lot of the dust off its solar panels and is in great shape. Spirit less lucky at the moment, but its happened for both of them multiple times in the past, and may well happen again.
So unless it were to hit near enough to dump substantially sized debris on one of the rovers (it sounds like Opportunity's side of the planet will be facing when it passes), the odds of survival seem pretty good to me.
If it does hit, it will be a fantastic opportunity for observing the effects of impacts on a rocky planet (remember how excited the astronomy community was when Shoemaker-Levy 9 hit Jupiter a few years back?), and we're well equipped to observe it in detail. First of all, Mars is nearly at it's closest approach to earth, so viewing from Hubble and ground scopes will be optimal.
Secondly, as mentioned the rovers may be able to observe the entry and impact. They could also measure the opacity of the debris cloud and how it spreads, and perhaps even measure some of the minerals thrown up using the Mini-TES instrument.
Third, there are three orbiters operating around Mars at the moment. All of them have pretty decent cameras on them to study before and after pictures of any crater, watch the debris cloud expand from above, and perhaps even fly through the debris to sniff it out and look for clues of buried water thrown up by the impact. Mars Express and Mars Reconnaissance Orbiter both have spectrometers that may be useful for that, and a couple of climate instruments that can investigate the effects on Mars atmosphere. The science teams may also come up with some clever ways to get bonus science, too. For example, when Cassini flew through the outer rings of Saturn, NASA measured the density and size of the ring particles by recording bursts of radio noise generated as tiny bits of dust vaporized against her high gain antenna.
The summary also says that Boeing will be the prime contractor for the Ares 1. This is not true. The article is about Boeing being the prime contractor for the avionics. Incidentally, Boeing is also the prime contractor for the second stage structure. However, the first stage is being built by Alliant Techsystems (who also makes the nearly identical shuttle SRB's...that part of the contract was a shoe-in), the 2nd stage engine is being built by Pratt and Whitney, and the Orion spacecraft that the Ares is being designed to launch is contracted to Lockheed Martin.
Can't we simply vote for it to land on Cowboy Neal?
Sorry, had to get that in there. I couldn't help but feel the summary was asking us for our uninformed opinion.
It sounds to me like you're talking about the requirement that has been with the system from the beginning that it be able to ditch in the ocean, regardless of the nominal landing profile. What NASA is trying to decide now is if it should normally land in the ocean and face the added recovery hassle and risk, or on land and need to accomodate the added 1500 pounds of weight plus more complexity (it will either have to discard the heat shield in flight, which may be a falling debris hazard, or have dropout panels for the airbags to deploy through). Water landing is a requirement. Dry landing is an option.
Until just recently, NASA and Lockheed had moved ahead with plans for touchdown on land. However, there's been a lot of discussion over the past two years about the need to keep the weight down. They already reduced the diameter of the capsule by half a meter to keep the capsule within the weight budget. I think also the service module is above its original weight targets, and either the SRB or the second stage performance is below its original goal.
In the discussion section of the article, someone suggested doing an air capture, much like how the Air Force used to retrieve film capsules from the Corona spy satellites by snagging their parachutes and realing them in. However, I don't think he realized that those capsules weighed a few dozen pounds, while Orion will weigh around 8.5 tonnes. NASA also planned to do mid-air capture of the Genesis capsule, which was carrying solar wind particles. Unfortunately, the parachute failed to deploy and it dug a crater in New Mexico.
For comparison, Soyuz lands on dry land in Kazakhstan. Instead of airbags, it has a set of small retrorockets on the bottom that fire just before touchdown to slow from the 24 ft/s rate of the parachute to just 5 ft/s (5.5 km/hr). I'm not sure how they deal with fire through or around the heat shield.
Sorry if I'm misreading your post, but what I was saying in my original post is that the matter the article is dealing with is a completely separate issue in astronomy from dark matter. You seem to be interpreting it as saying dark matter is probably actually normal matter. I won't get into that debate here but just want to clarify that this is not what either the paper or I was suggesting.
Dark matter was detected gravitationally and generally believed to be non-baryonic. The matter in question has not been detected at all, but is thought to exist based on the current models of how the universe was formed. Dark matter appears to make up 25% of the mass/energy in the universe. The matter the article discusses in only about 2%.
Also, from my interpretation of the article and prior reading, it shouldn't be dust, but simply vast clouds of mostly hydrogen and some helium gas. This stuff would reside in the huge volumes of space between the galaxies and would never have achieved sufficient densities to collapse into stars where it could be fused into the heavier atoms necessary to form space dust. At the distances, densities, and temperatures involved, it would be undetectable with our current technology.
And of course, there is free gas and dust that we are able to see in the Milky Way and neighboring galaxies, but this also is a separate issue.
Since I'm sure the question will be asked, no this missing mass is not dark matter, as both the summary and the article are clear to emphasize. I wanted to repeat that. The primary evidence for dark matter is the galactic rotation curves. The article is talking about gaseous normal matter that we believe exists, but hasn't spotted yet. This missing gaseous matter is nowhere near sufficient in mass to explain the gravitational effect of dark matter and is being looked for on a scale larger than galaxies. The missing mass is an estimate 2% of the mass of the universe, whereas dark matter is an estimate 25%.
SpaceX is currently 0 for 2 on attempts to reach orbit (although they claim reaching orbit was a secondary objective of their test flights so far, so the second one was counted as successful based on the demonstration of operation of all components up to second stage ignition). They are still developing the launcher big enough to orbit a manned capsule, as well as the capsules themselves. The other COTS candidate was just re-picked last month after Rocketplane Kistler failed to meet objectives stipulated under the contract. They're years behind where SpaceX is, aside from the fact that one of their partners, ATK Thiokol, already has shown they know how to build boosters (they make the shuttle SRB's). Whether that team can put together the whole system on time and economically enough is still a big question.
On the other hand, the Orion project has an added bit of (expensive) security in the form of their long history of being the experts, and the more substantial funding available. In short, they have resources not provided by COTS.
More importantly, the COTS proposals aren't good enough for what NASA wants Orion to do, which is basically become the standard people mover for the next several decades. While it may seem like a step back from SpaceX's Falcon 9/Dragon combo with only 6 passengers instead of 7, it actually has quite a bit more versatility, with sufficient delta V for additional manuevering, sufficient control to dock itself, supplies for longer missions, and intentional adaptability for other missions. This includes being able to survive re-entry from a lunar-earth trajectory or even a Mars-earth trajectory, and being able to steer significant amounts during re-entry for easier recoverability. NASA actually envisions attaching an Orion capsule to a spacecraft returning a crew from Mars, which would separate as it approached earth.
COTS is only bank-rolling on the capability to reach the ISS, be docked with assistance from the robotic arm, and deorbit safely.
Way over 45% of the videos on youtube about the WTC attacks have "harmful scientific misinformation." It's probably closer to 99% of those.
And no wonder. People with degrees in economics (if any degree at all) make a slideshow with a narration denying engineering phenomena that have been documented for around a century like metal creep at elevated temperatures, and youtube viewers lap it up like water.
Sorry to make a Godwin's law topic change, but no one should be surprised that there's a disappointing amount of misinformation in youtube videos. There's seldom any expertise consulted in making them, and almost never any scientific method utilized in the original statements. Seriously, you might as well ask the dog that rides a skateboard for medical advice as refer to an unaccredited youtube production.
Did no one read the article? It says they're investigating a possible leak. They haven't even confirmed it isn't a miscalibration or some other spurious data.
For comparison, there's about 400 kg of free air inside the space station, and the purported 1.3 kg per day leak isn't even enough to show up as a pressure drop.
I checked NASA's ISS site, and there doesn't seem to be any mention of a leak there yet. The latest update does mention leak checks between the brand new Harmony module and the shuttle docking adapter which was moved to Harmony's forward port but has not yet had the Harmony-side hatch opened. Presumably the purported leak is related to these checks, but that isn't clear.
The whole manned space program from mercury to apollo cost $25 billion.
1.) NASA's budgets from 1958 (inception) to 1973 (end of the Apollo program) add up to $56.7 billion. I'm not sure how much was on Mercury and Gemini, but over $19 billion was on Apollo alone.
2.) There's a little thing called inflation that you failed to take into account. Using the consumer price index, the Apollo expense were $135 billion. In 1966, NASA spent 1.8 times as much in adjusted dollars as their budget for 2007 (note: numbers in this paragraph are derived from wikipedia and don't quite match NASA's published numbers).
3.) I have no idea where you got the figure of $100 million for a Saturn V. NASA spent $6.4 billion on the Saturn V, and launched 13 vehicles, 10 of them manned. That's $492 million per launch, and from the link above you will see that it does not include the CSM, lander, or mission costs.
4.) Just a perspective of modern launch costs shows your numbers are almost certainly skewed. A Titan IV, which had a payload slightly less than the space shuttle but is unmanned cost over $250 million.
5.) The largest of the proposed Saturn derivatives would have peaked out at 260,000 kg LEO capability, but that doesn't matter since those were abandoned in the 60's or 70's.
6.) Another poster addressed the myth that the shuttle has to be rebuilt from the ground up, but I'll repeat it since the myth seems to come up incessantly. The shuttle is thoroughly cleaned and inspected, any repairs or maintenance needed is performed, damaged tiles replaced, and the engines tested. The solid rocket boosters are refurbished and reloaded, and a new external tank is fitted. This is most definitely not a rebuild.
7.) The arguments versus the shuttle are somewhat irrelevant since the ISS components were mostly designed around the shuttle cargo bay and with the shuttle's capability as a work platform in mind. Additionally, the limiting factor on many of the payloads has been not mass, but crew hours available to install them and launcher volume. And don't forget, the launch capacity of the Saturn V is before crew accomodations. For the shuttle, it's after.
8.) The discussion here was a Mars mission, and NASA is developing a more advanced launcher that would eventually contribute to that purpose. The Ares V will have a 130 mT LEO capability, compared to 118 mT for the Saturn V. NASA hasn't made a lot of cost projections, but looking at the infrastructure required and the types of components being used, I'm guessing the Ares V will be around $500-750 million per launch, not counting development costs. I'd figure $150-250 million for manned Ares I missions.
No, that's with the fixed costs of extending the program apportioned. Sorry, I don't remember where my original source for this was, but I'm pretty certain on this point. The sub $100 million figure is just the costs of reprocessing the orbiter and conducting the launch. That does not, however, include initial investment in design and infrastructure, and a bunch of similar miscellaneous costs like the return-to-flight work, which inflate the number further to about $1.3 billion per flight.
NASA is considering adding two more missions to the manifest for early 2011, and I think they're looking at around half a billion as the estimated cost to the shuttle program, not counting the payload, which I believe comes out of the ISS budget.
Also, the $100 million figure for a Saturn V quoted further up in the discussion is bogus, except perhaps in ~1970 dollars. NASA spent $6.5 billion on the Saturn V program from 1964 to 1973 and conducted 13 launches, three of them unmanned. That's $500 million per launch not adjusted for inflation.
You can darn well bet that a Saturn V would cost over $100 million today. The Delta IV heavy, a more modern but much smaller rocket costs over $200 million per launch. The similar-sized but older Titan IV costs about $250 million per launch, which is why it was retired. Even SpaceX's Falcon 9 Heavy, also about the size of the Delta IV, is expected to cost $90 million, raising serious skepticism from many in the launch services industry because the proposed number is so much cheaper than anything in its class.
First of all, I wanted to question whether anybody knew if they had any customers for this satellite bus? The two photos looked more like non-flight testbeds than shiny, thermally controlled satellites we're used to seeing.
Second, does anyone know if a magnetic orientation system has been used on any satellites in the past? Obviously, the rotation rates that can can be achieved by such a system must be pretty low, especially if the satellite has no moving parts to extend booms, so I'm curious what sort of payloads this bus is useful for.
Third, one of my first thoughts is it sounds like they might be specifically targeting themselves at SpaceX. With the 1400 pound LEO capacity of the Falcon 1 for $8 million, it's the only rocket that could put one of these things (perhaps two) into space for the $10 million estimated in the article. Even the current low cost contender in the US, the Orbital Sciences Minotaur, which reuses SRB's from retired Peacekeeper missiles, costs over $12 million per rocket, not counting payload integration and launch, as I understand it.
Lastly, the article says this satellite would be a competitor with the Falcon 1, which is obviously false. The Falcon 1 is a launch vehicle. FASTSAT is a satellite. They go together, not compete.
Mars Rover and MER in your response are the same thing. The Space.com article is very out of date, and they had some cost overruns after that which pushed the mission to $820 million, which included I believe the first year of operations and science. I believe NASA has spent another couple hundred million on operations and science due to the extensions...a lot of money, but a lot less than equivalent new missions.
Also, the Mars Science Laboratory currently being built for a launch in 2009 is looking to cost around $1.8 billion USD (a little over a billion Euros, IIRC). It will be nuclear-powered, land completely ready to go instead of in those nifty airbags the MER's came in on, and is roughly the size of a Volkswagen (which is why the airbags won't work). It's supposed to last about 2 years, so if it runs the way the MER's have, NASA will still be trying to kill it off 20 years from now (just kidding...that's ridiculously unlikely).
MSL also ran into budget issues, and has increased in cost several times over the last couple of years, so NASA recently cancelled two rather fascinating instruments to keep the cost down. The first was the descent imager, which I'm not sure how much scientific value it would've had, but the time-lapse video of the descent would have been fascinating. The other was the ChemCam, a marvelous laser and spectrometer combo that would allow scientists to analyze the chemical composition of rocks from up to 40 feet away. However, the descent imager on the Mars Phoenix Lander currently en route turned out to have a fatal flaw, so the operations budget for that got switched to the construction budget for the MSL. Also, the Chemcam team realized that it had come down to defeaturing the Chemcam or not flying it all, and went with the former option to get back in budget. They got some extra money that was saved because Mars Phoenix launched on time. Unfortunately, the sweet zoom capability of the mast camera was cut out and not re-instated.
The CIA world fact book says 2004 electrical production (not counting transportation energy, etc) was 17.4 trillion kW-hours, so we'd need at least 2 TerraWatts of capacity. A relatively large nuclear reactor produces about a GW of electricity, which translates to 2000 plants. Add in other energy needs currently met by fossil fuels and account for capacity factors and that CalTech professor you reference is probably within an order of magnitude of the actual need.
The problem with that argument is it only demonstrates the scope of our energy needs. It says nothing about the feasibility of nuclear versus other technologies, and ignores the fact that the exact same challenge applies to any energy source. To cover our needs with just coal (currently 25% of the world energy supply and something like half of the electrical supply) would similarly require about 10,000 coal plants. You want to it with wind? You need roughly one million of today's highest capacity wind turbines. Solar? About $20 trillion dollars worth of solar panels near the equator will do it. Hydro? Well...forget about that one. Hydro power options are mostly in use in developed countries.
We'd run out of nuclear fuel in decades (actually, I've been told centuries) if we continued to utilize it as poorly as we currently do. Reprocessing, however, can dramatically increase the available energy from existing fuel and potentially the economics of developing new mines. Not to mention reducing the waste by 90% or so.
Don't forget we're just talking about nuclear fission here. If we can get fusion working commercially, the picture changes.
Anyone who thinks we'll get all our energy from one source in the foreseeable future, however, is out of the loop.
The HD camera on SELENE is a PR instrument. Video is useful for things that change. The moon, for the most part, does not change, and the HD camera does not produce scientifically useful images of the moon. SELENE can only take about a minute worth of video.
High Definition as a proper noun generally refers to 1920x1080 resolution, but the various space agencies have produced much higher resolution images for years. The 35mm film shot during the Apollo missions is being scanned into 3070x2044 pixel images, for example, and the medium format film is being scanned at a huge 12800x12800 pixels. The Mars rovers carry 1 MP (1024 x 1024) cameras, and the images are often stitched together into far larger mosaics. I've seen some that even as JPG's take up over 100 MB (and crash IE). The Hubble Space Telescope's highest resolution camera is also only 1024x1024 pixels, and I believe this was chosen to approximate the maximum resolution of the optics, but again, large mosaics are common.
The High Resolution Imaging Scientific Experiment (HiRISE) camera aboard the Mars Reconnaisance Orbiter takes a different approach and is what's called a "push broom camera." Instead of taking rectangular pictures every so often, it scans a single line of up to 20,000 pixels continuously at the rate the spacecraft moves over the ground. In this way it builds up images up to 40,000 pixels long (800 megapixels...now that's high def!), at which point the file has to be transmitted to earth or the camera runs out of memory.
There is this account of a Russian attack sub tailing a U.S. super carrier, and the captain of the carrier ordering increasing amounts of speed to see if the sub could keep up. There was a certain sobering factor that the sub was able to match whatever speed the carrier could reach. Above a certain speed, the sub was going so fast and making so much noise that there was no longer any sub stealth involved, but there was a command decision about whether to go even faster to see if the sub could keep up. On one hand, the sub is giving up intel about how fast it can go, but the carrier is giving up intel on its speed, and the account was that the captain of the carrier gave up on attempting to outrun the sub to not reveal what the carrier could do.
It sounds like you've read Tom Clancy's Submarine. It sometimes amazes me what military personel will tell him anonymously.
Every indication I've seen is that this is a true story. The ship was the USS Enterprise, our first nuclear-powered carrier. The tail was a Soviet November class submarine, one of their early nuclear-power attack boats. They were surprised to find it chasing them at 30 knots, an ability that was later explained by saving weight on reactor shielding (The running joke is that Soviet sub crews glow in the dark). It was probably equally as surprising that the sub could track the carrier while making so much noise itself, much less maintain that speed. The problem wasn't that the Enterprise had reached its top speed, but that her combustion-powered escorts had.
The captain of the sub may not have known he was being tracked (helicopters using sonar buoys are pretty discrete, and surface ships have an even worse time hearing over their own din than submarines, something the Russian captain would have known), while the Americans could bet the Russians knew the Enterprise could easily reach those speeds with plenty of power to spare.
This Chinese sub popping up within range of a battle group (modern torpedoes have a range more than twice that, although by running flat out away they might still have been escaped damage) isn't a show of stealth or technology so much as it is of cleverness and planning. Electric boats are not very fast, but they're darn quiet, even older designs. If the captain can successfully guess its course, which might not be very hard absent a reason to zig zag, he just has to make a dash to get in its path while it's still distant, then manuever at a silent crawl to exactly where he wants to be. It can literally be quieter than the water around it. So all they're really telling us by sneaking into the middle of a battle group is that they have sub drivers with the guts and smarts to do so.
And of course it's also possible, as suggested, the sub found itself there inadvertantly and surfaced to avoid any misinterpretation of hostile intent.
If you're up for a reading recommendation, Larry Bonds does an excellent job of portraying this dash-and-wait tactic for a chapter of Red Phoenix. Or there is the riveting real-life account of the sinking of the largest Japanese carrier in WWII in Shinano!
Also, remember how long ago this happened. There was an expedition there but they didn't have the technology we did. I'm not sure if the tree patterns would help you 100 years later.
Yes. Something that is easy for us to forget is that they didn't have roads, or even much in the way of all terrain vehicles, much less helicopters or satellites when this occurred. Not to mention, it was largely ignored until after the revolution and WWI were both finished up with. The first aerial photographs taken of the site were taken 30 years later and still clearly showed the fall pattern, but no crater was visible.
It's easy to look at the pictures and think you can simply follow the trees all the way to the center. Way easier said than done. First of all, the site is pretty much in the middle of nowhere. There's just a few scattered villages, no doubt with abysmal roads between each and almost nothing traversable with wheels leading anywhere else. They would have walked or ridden pack animals for the entire survey.
It's also a huge area. 80 million trees were felled over 830 square miles. Hunters (I've done my share) and loggers are probably familiar with trying to walk through such an area. The trees may look all neatly arrayed in a photograph, as if you could step easily from one to the next or walk between them like a trail, but the truth is far different. Without the perspective benefit from being atop a hill, the fall pattern is more difficult to discern. The branches will lie tangled, blocking the path at frequent intervals. The trunks will be random distances apart, some managing to overlap nearby trunks. They often sit several feet above the ground, making it easy to fall and twist an ankle or knee, and exhausting to climb over again and again and again. Vegetation will have sprouted up in the 19 years between the fall and Kulik's arrival, leaving a tangled mess of shrubs and briers that sometimes appear deceptively solid from above and forboding from ground level. A mile per hour is a decent speed walking through such an area with several days worth of supplies on your back.
But Kulik actually did push through to the center, and he found several trees standing upright, stripped of their branches, consistent with an airburst from above. He also found a bog he was convinced was a crater, but when he drained it there were old tree stumps at the bottom. For an impact to have formed the bog the blast would have shattered the old trees and tossed the remains out of the muddy crater.
Oops...yes, that should have been 0.035% of the helium on the moon is He-3 and 0.000138% of helium on earth is He-3. Not only did I copy the same number down twice, I misplaced a decimal point.
As I understand it, the difference is because most of the He-3 on the earth is primordial...from the earth's formation. He-3 from the sun also strikes the earth, but is quickly lost again from the upper atmosphere. On the moon, there is primordial He-3 plus new stuff from the sun that gets trapped in the rock since there is effectively no atmosphere to slow it down before encountering the surface.
The dilution of He-3 on earth is also increased due to radioactive decay producing alpha particles (He-4).
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Are you talking about the same things as the rest of us? From reading this I'm pretty sure you don't know what you're talking about.
Pope Benedict XVI never said Galileo was wrong. He didn't even endorse the sentence against him. What he did, while he was still Cardinal Ratzinger, was quote some (agnostic, by the way) philosopher's opinion of the matter in relation to the revisionism that was occuring in the 18th century: "The church at the time of Galileo was much more faithful to reason than Galileo himself, and also took into consideration the ethical and social consequences of Galileo's doctrine. Its verdict against Gaileo was rational and just, and revisionism can be legitimized solely for motives of political opportunism."
You can not read this fairly without noting that Cardinal Ratzinger himself refers to this opinion as drastic. He favors the quote by Bloch saying, "Christianity has the right to remain faithful to its method of preserving the earth in relation to human dignity, and to order the world with regard to what will happen and what has happened in the world." Meaning basically that although physically the earth revolves around the sun, it's still the center of human activity.
This speech was two years before Pope John Paul II publicly apoligized for the way the church responded to Galileo. Cardinal Ratzinger never himself said the church was right in handling the Galileo affair, and he most certainly never supported geocentrism. However, it seems there's plenty of people who are happy to falaciously believe that claim, sadly including this supposedly well-educated Professor Cini.
You also don't appear to know what historically happened. The board of Inquisitors told Galileo and others not to publicly advocate heliocentrism. He was still permitted to discuss it hypothetically. Galileo had been vocally advocating it and creating quite a stir at the time, because a lot of sticks in the mud flat-out rejected it because they were ignorant, knee-jerk reactionists. He graciously agreed.
When Galileo's friend, Pope Urban VIII succeeded to the papacy, he returned to the subject. Urban actually requested he write a book on it, but again, not to press the arguments directly. However, he didn't hold very well to that condition, and actually used quotes from Urban in presenting Artitotelian viewpoint that ended up sounding rather mocking, although probably inadvertantly.
This public embarrassment unfortunately alienated the Pope, and the sticks-in-the-mud won out, forcing him to publicly recant the theory of heliocentrism, banning the book, and placing him under house arrest for several years.
Ironically, Copernicus had been teaching about heliocentrism 100 years earlier, and his theories were well-received at the time by several popes and innumerable academics. It took that long for the knee jerkers to gain support higher up and find a fittingly controversial victim.
This is true. I agree with this part. However, everytime the topic of ISRU comes up, I see plenty of armchair engineers talking lightly about applying it from the get-go at very, very advanced levels, and it's clear they haven't given any real thought to what it takes to achieve the sort of results they're talking about. One of the posters above, for example, dismisses building a pressure vessel for a habitat as fairly elementary. That first of all neglects the point about structural mass actually being a minority of the payload needs for a moon base, and secondly shows an ingorance of the large and specialized tooling needed to build such components here on earth. How much can that infrastructure actually be shrunk down, made lightweight, or made multipurpose by simply sacrificing productivity?
As I said, I agree if we're going to live in space truly long term, we need to learn to use the resources out there. Once we reach the trade surplus point, we'll have reached that dream of the lunar-industrial age. But it seems like everyone is assuming with a little clever engineering we can do that right now. That's not so. It will take a herculean amount of engineering, testing, re-engineering, failing, succeeding, and taking baby steps to get there.
That's why the first resource utilization will be simple things. Once you've established a baseline competancy, it's easier to add on to it than to do the whole thing all at once. It also leaves you in a better and less expensive position to react to problems or unanticipated supply or demand changes.
On the point about sending unmanned missions first. That is actually part of the plan. NASA decided last year they should identify several targets on the moon of scientific interest and send short "sortie" mission similar to the Apollo program there. At the same time, they would also pick a site for a permanent base and land equipment there in advance of a crew. Right now it looks like two missions to send power, basic supplies, and a basic habitat. Then short manned mission to get everything set up. This would be followed by a longer missions with stuff like ISRU equipment, a pressurized rover for long exploration missions, and additional living/science facilities.
Unfortunately, such things are not as easy in real life as they are in star trek. Have you seen even small processing operations here on earth? Even when you know exactly what you're working with, it has a high percentage of what you want, and the wheat is easily separated from the chaff, it takes a large piece of rather expensive machinery to accomplish it. Wheat and chaff case in point: a typical John Deere combine weighs about 12 tons. All it does it cut wheat, seperate the kernels from the heads, and dump the straw out the back. And it needs gas and air in sufficient quantities to produce about 200 hp to operate. Obviously that's a high volume farm implement, not an optimized space tool, but I stand by the basic point.
Think about what that extensive mineral utilization entails. You're limited by what's up there. The lunar regolith is mostly aluminum oxide, silica, and some calcium, with trace amounts of various gasses like hydrogen and helium. Suppose then you want fiberglass. That's an easy one. You suspend the regolith in a liquid and separate the silica from the alumina based on density. Then you melt the silica and blow it out of a fine nozzle to form strands. Unless you can figure out how to do it in a vaccuum, however, which is plausible, you need a gas to blow it, either brought from earth or boiled out of the regolith.
That right there is five primary subsystems:
1.) Power
2.) Regolith collector
3.) Silica separator
4.) Furnace and fiber machine
5.) Gas storage and/or production.
But fiberglass is all but useless without epoxy, and making fiberglass parts is a messy, complicated job here on earth. You'd be crazy to stake the success of your lunar base on the ability for a self deploying robot to produce useful and quality controlled parts on the moon. Not to mention, all you've got at that point is structural parts, which are only a fraction of the mass of supplies you need.
You could look at the same needs for producing aluminum. It gets really interesting when you start looking at the mass of equipment needed to produce sheet aluminum out of cast ingots. The raw aluminum itself is very energy intenstive to produce, requiring 7.5 kW-hours of electricity per pound to reduce from alumina in high volume smelters.
And I'm not even going to get started on what it takes to make complex shapes like a pressurized habitat or a seal for an airlock.
All of this is why NASA is looking at landing all the needed supplies on the moon and practicing the techniques with human involvement from the start. The first supplies produced will probably be oxygen (which can be electrolytically separated from the silica, alumina, or small amounts of ice present on the moon), and bricks for radiation protection and insulation sintered from the raw regolith.
Start simple. As you show you can make useful items from simple processes, then you add complexity.
Mine was on the Vic-20, the Commodore-64's immediate predecessor. The first was a simple Basic counting game that I think my mom wrote as part of a programming tutorial. I'm guessing I was about three years old at the time.
My first commercial game was probably Tooth Invaders. You were a toothbrush, running around on a set of 2-D teeth, removing plague. Germs would wander around depositing plague and could kill you. If enough plague accumulated, you'd get a cavity and lose. Graphics quality put Strong Bad's "Duck Pond" to shame. After that it was Mole Attack, Moon Base, and the best game available at the time: Choplifter.
After we got a 286, I spent quite a bit of time on the first edition of Microsoft Flight Simulator, flying a 172 out of Midway, amusing myself sometimes by flying into the Hancock building.
Aww...the memories. I should go find an emulator and ROM's for all these.
You're quite right on the basic principle: Corn stalks (aka stover) can be used as the ethanol feedstock. However, my understanding is that the plans are to ramp up ethanol production beyond what corn stover alone could produce, and there is some limited other use of the corn stocks for feed and mulch.
It sounds like the reason the waste isn't currently used is merely that no one has built the plants. The initial round of plants being built rely heavily on waste material like this.
By the way, here is the original wikipedia article I referred to. It covers the production methods and refers to several research studies that have been conducted investigating the feasibility of ethanol as a supplemental fuel. It does not appear to be viable as a complete replacement for gasoline, however.
http://en.wikipedia.org/wiki/Cellulosic_ethanol Re-reading it, I believe I've understated the known scalability of cellulosic processes, as there are several commercial demonstration plants in operation or under construction producing millions of gallons per year. As noted, however, they currently cost more up front than corn ethanol plants. Also, there are claims that I haven't yet cared to look into that the corn industry has successfully lobbied to maintain an advantage for the development of corn-based ethanol production. A little short-sighted, I would think, since rather than planting more crops, the farmers could be getting greater return on existing crops by selling more of their waste.
This has been circulating around the intarwebs for a few days now, so it spurred me to do some background reading already.
Corn has higher amounts of the simpler sugars that bacteria need to work on to produce the ethanol. Switchgrass and other cellulosic feedstocks, which are largely equivalent in feasbility in general terms, have those sugars bound up in...you guessed it...cellulose. Because of this it requires much more processing prior to fermentation. There are several ways to do this with varying costs and efficiencies, but at the very least is technically viable.
However, this pre-processing and the fact that large-scale cellulosic ethanol production is a new technology means the initial costs are higher. According to Wikipedia (with original sources referenced), corn ethanol plants cost about $1-3 per gallon of annual capacity to construct. The first round of large scale cellulosic ethanol plants now under construction are billed about $7 per gallon of annual capacity. Production costs are expected to run about $2.25 per gallon initially, or about $125 per barrel of oil energy equivalent.
However, as the method is proven, that cost is expected to come down. About $350 million of cost is also being funded by the federal government under the new energy plan. Also, the cost of the feedstock for cellulosic ethanol production is much lower, as it can use switchgrass as mentioned in the summary, corn stover, wood chips, or just about anything else containing plant matter, where as the corn method requires corn (duh), and thus competes with food production.
Of course, the article makes the energy-return benefit over corn ethanol obvious. Elsewhere it has been estimated that cellulosic ethanol production could account for 30% of our transportation energy needs in a couple decades. Obviously far short of weaning us off foreign oil, but a start nonetheless. However, an added benefit of using grasses like switchgrass is the fields don't have to be replanted every year, reducing soil depletion and erosion.
We've learned with near certainty that there were large amounts of liquid water on Mars in the past. This shows that Mars was almost certainly more like Earth in its past, may still maintain some suitability for human life, and brightens hopes of finding extra-solar, earth-like planets.
We've studied the geological history of Mars in detail that was utterly impossible via any other means short of landing actual people there. This hints at the similarities and differences between Mars and Earth and may help us better understand how our own planet evolved and operates.
We've studied the Martian atmosphere in reasonable detail and gathered more information on its climate. If we ever find it beneficial to try living there (or decide to do so regardless of benefit), this information will be vital.
We've developed and tested a new set of scientific tools, robotic components, autonomous navigation techniques, etc. Several of these were new to the mission.
We've produced thousands of stunning images of an alien surface. That alone is certainly worth as much as public art. Nothing inherently makes the Statue of Liberty, for example, more valuable than Mars Rovers...or, at the risk of sparking the public-vs-private money debate, those big screen TV's everyone has to have.
And we've helped inspire further generations of youth to study science and math.
NASA actually is quite forthcoming with information about their discoveries, but the general public often cares little for more than the most basic details, and thus the private news media usually only give passing mention to NASA press releases. If you're genuinely curious to learn more about the rovers' work, browse through old press releases on the website:
http://marsrovers.jpl.nasa.gov/home/index.html
While I agree some strict budget control measures are long called for, I'm afraid the above quote isn't quite true. I'm having a lot of trouble thinking of missions that fit your description: successful, focused, not big spenders. Mars Pathfinder probably, although it wasn't necessarily a really focused mission. It was primarily a technology demonstrator. Stardust, Deep Impact, Mars Odyssey, and Mars Global Surveyor all get nods. But on the other hand:
The issue here is that NASA comes up with some really nifty missions, but underestimates the cost and sometimes mis-manages programs, as you've described. However, some of the missions are just too good to let go of, so they continuously eat the cost overruns and delays because they really want the science a particular mission is going to allow. Other times they've invested so much in a mission they don't want to throw all the investment out, and they pay the extra just to make sure they get something out of it. I may have said the MER's didn't have real clear objectives, but NASA knew they had versatile machines and dug up the extra money because they knew they could work with whatever they found on the surface.
The James Webb Space Telescope is an even better, and more current example. It's had features removed or downsized several times, but has still suffered explosive cost growth and delays. However, every time it gets reviewed, the science guys say they absolutely must have this mission and other things get cut to pay for it.
We have most definitely tested nuclear weapons on, above, and below the ground. The Trinity test was only about 100 meters above the ground and kicked up a fair amount of dust, but it definitely did not spread globally.
The impact, should we be fortunate enough to witness one, will no doubt kick up a huge amount of dust over an area of a couple dozen square miles. However, the total energy of this impact is likely to pale compared to even a modestly sized dust storm, and as the cloud spreads out over thousands of square miles, the opacity will drop quickly.
NOAA says that a fully developed hurricane releases 10 megatons of energy every 20 minutes. The storm Opportunity and Spirit endured a few months ago was lower intensity but far, far larger in scale than a hurricane, and it lasted for weeks. Opportunity, fortunately, had a stiff breeze later blow a lot of the dust off its solar panels and is in great shape. Spirit less lucky at the moment, but its happened for both of them multiple times in the past, and may well happen again.
So unless it were to hit near enough to dump substantially sized debris on one of the rovers (it sounds like Opportunity's side of the planet will be facing when it passes), the odds of survival seem pretty good to me.
If it does hit, it will be a fantastic opportunity for observing the effects of impacts on a rocky planet (remember how excited the astronomy community was when Shoemaker-Levy 9 hit Jupiter a few years back?), and we're well equipped to observe it in detail. First of all, Mars is nearly at it's closest approach to earth, so viewing from Hubble and ground scopes will be optimal.
Secondly, as mentioned the rovers may be able to observe the entry and impact. They could also measure the opacity of the debris cloud and how it spreads, and perhaps even measure some of the minerals thrown up using the Mini-TES instrument.
Third, there are three orbiters operating around Mars at the moment. All of them have pretty decent cameras on them to study before and after pictures of any crater, watch the debris cloud expand from above, and perhaps even fly through the debris to sniff it out and look for clues of buried water thrown up by the impact. Mars Express and Mars Reconnaissance Orbiter both have spectrometers that may be useful for that, and a couple of climate instruments that can investigate the effects on Mars atmosphere. The science teams may also come up with some clever ways to get bonus science, too. For example, when Cassini flew through the outer rings of Saturn, NASA measured the density and size of the ring particles by recording bursts of radio noise generated as tiny bits of dust vaporized against her high gain antenna.
The summary also says that Boeing will be the prime contractor for the Ares 1. This is not true. The article is about Boeing being the prime contractor for the avionics. Incidentally, Boeing is also the prime contractor for the second stage structure. However, the first stage is being built by Alliant Techsystems (who also makes the nearly identical shuttle SRB's...that part of the contract was a shoe-in), the 2nd stage engine is being built by Pratt and Whitney, and the Orion spacecraft that the Ares is being designed to launch is contracted to Lockheed Martin.
Can't we simply vote for it to land on Cowboy Neal?
Sorry, had to get that in there. I couldn't help but feel the summary was asking us for our uninformed opinion.
It sounds to me like you're talking about the requirement that has been with the system from the beginning that it be able to ditch in the ocean, regardless of the nominal landing profile. What NASA is trying to decide now is if it should normally land in the ocean and face the added recovery hassle and risk, or on land and need to accomodate the added 1500 pounds of weight plus more complexity (it will either have to discard the heat shield in flight, which may be a falling debris hazard, or have dropout panels for the airbags to deploy through). Water landing is a requirement. Dry landing is an option.
Until just recently, NASA and Lockheed had moved ahead with plans for touchdown on land. However, there's been a lot of discussion over the past two years about the need to keep the weight down. They already reduced the diameter of the capsule by half a meter to keep the capsule within the weight budget. I think also the service module is above its original weight targets, and either the SRB or the second stage performance is below its original goal.
In the discussion section of the article, someone suggested doing an air capture, much like how the Air Force used to retrieve film capsules from the Corona spy satellites by snagging their parachutes and realing them in. However, I don't think he realized that those capsules weighed a few dozen pounds, while Orion will weigh around 8.5 tonnes. NASA also planned to do mid-air capture of the Genesis capsule, which was carrying solar wind particles. Unfortunately, the parachute failed to deploy and it dug a crater in New Mexico.
For comparison, Soyuz lands on dry land in Kazakhstan. Instead of airbags, it has a set of small retrorockets on the bottom that fire just before touchdown to slow from the 24 ft/s rate of the parachute to just 5 ft/s (5.5 km/hr). I'm not sure how they deal with fire through or around the heat shield.
Sorry if I'm misreading your post, but what I was saying in my original post is that the matter the article is dealing with is a completely separate issue in astronomy from dark matter. You seem to be interpreting it as saying dark matter is probably actually normal matter. I won't get into that debate here but just want to clarify that this is not what either the paper or I was suggesting.
Dark matter was detected gravitationally and generally believed to be non-baryonic. The matter in question has not been detected at all, but is thought to exist based on the current models of how the universe was formed. Dark matter appears to make up 25% of the mass/energy in the universe. The matter the article discusses in only about 2%.
Also, from my interpretation of the article and prior reading, it shouldn't be dust, but simply vast clouds of mostly hydrogen and some helium gas. This stuff would reside in the huge volumes of space between the galaxies and would never have achieved sufficient densities to collapse into stars where it could be fused into the heavier atoms necessary to form space dust. At the distances, densities, and temperatures involved, it would be undetectable with our current technology.
And of course, there is free gas and dust that we are able to see in the Milky Way and neighboring galaxies, but this also is a separate issue.
Since I'm sure the question will be asked, no this missing mass is not dark matter, as both the summary and the article are clear to emphasize. I wanted to repeat that. The primary evidence for dark matter is the galactic rotation curves. The article is talking about gaseous normal matter that we believe exists, but hasn't spotted yet. This missing gaseous matter is nowhere near sufficient in mass to explain the gravitational effect of dark matter and is being looked for on a scale larger than galaxies. The missing mass is an estimate 2% of the mass of the universe, whereas dark matter is an estimate 25%.
Also, I though it interesting that the is a very interesting rendition of the nearby universe. It's not related to the article, but it does show the filamentary structure the article talks about.
SpaceX is currently 0 for 2 on attempts to reach orbit (although they claim reaching orbit was a secondary objective of their test flights so far, so the second one was counted as successful based on the demonstration of operation of all components up to second stage ignition). They are still developing the launcher big enough to orbit a manned capsule, as well as the capsules themselves. The other COTS candidate was just re-picked last month after Rocketplane Kistler failed to meet objectives stipulated under the contract. They're years behind where SpaceX is, aside from the fact that one of their partners, ATK Thiokol, already has shown they know how to build boosters (they make the shuttle SRB's). Whether that team can put together the whole system on time and economically enough is still a big question.
On the other hand, the Orion project has an added bit of (expensive) security in the form of their long history of being the experts, and the more substantial funding available. In short, they have resources not provided by COTS.
More importantly, the COTS proposals aren't good enough for what NASA wants Orion to do, which is basically become the standard people mover for the next several decades. While it may seem like a step back from SpaceX's Falcon 9/Dragon combo with only 6 passengers instead of 7, it actually has quite a bit more versatility, with sufficient delta V for additional manuevering, sufficient control to dock itself, supplies for longer missions, and intentional adaptability for other missions. This includes being able to survive re-entry from a lunar-earth trajectory or even a Mars-earth trajectory, and being able to steer significant amounts during re-entry for easier recoverability. NASA actually envisions attaching an Orion capsule to a spacecraft returning a crew from Mars, which would separate as it approached earth.
COTS is only bank-rolling on the capability to reach the ISS, be docked with assistance from the robotic arm, and deorbit safely.
Way over 45% of the videos on youtube about the WTC attacks have "harmful scientific misinformation." It's probably closer to 99% of those.
And no wonder. People with degrees in economics (if any degree at all) make a slideshow with a narration denying engineering phenomena that have been documented for around a century like metal creep at elevated temperatures, and youtube viewers lap it up like water.
Sorry to make a Godwin's law topic change, but no one should be surprised that there's a disappointing amount of misinformation in youtube videos. There's seldom any expertise consulted in making them, and almost never any scientific method utilized in the original statements. Seriously, you might as well ask the dog that rides a skateboard for medical advice as refer to an unaccredited youtube production.
Did no one read the article? It says they're investigating a possible leak. They haven't even confirmed it isn't a miscalibration or some other spurious data.
For comparison, there's about 400 kg of free air inside the space station, and the purported 1.3 kg per day leak isn't even enough to show up as a pressure drop.
I checked NASA's ISS site, and there doesn't seem to be any mention of a leak there yet. The latest update does mention leak checks between the brand new Harmony module and the shuttle docking adapter which was moved to Harmony's forward port but has not yet had the Harmony-side hatch opened. Presumably the purported leak is related to these checks, but that isn't clear.
1.) NASA's budgets from 1958 (inception) to 1973 (end of the Apollo program) add up to $56.7 billion. I'm not sure how much was on Mercury and Gemini, but over $19 billion was on Apollo alone.
2.) There's a little thing called inflation that you failed to take into account. Using the consumer price index, the Apollo expense were $135 billion. In 1966, NASA spent 1.8 times as much in adjusted dollars as their budget for 2007 (note: numbers in this paragraph are derived from wikipedia and don't quite match NASA's published numbers).
3.) I have no idea where you got the figure of $100 million for a Saturn V. NASA spent $6.4 billion on the Saturn V, and launched 13 vehicles, 10 of them manned. That's $492 million per launch, and from the link above you will see that it does not include the CSM, lander, or mission costs.
4.) Just a perspective of modern launch costs shows your numbers are almost certainly skewed. A Titan IV, which had a payload slightly less than the space shuttle but is unmanned cost over $250 million.
5.) The largest of the proposed Saturn derivatives would have peaked out at 260,000 kg LEO capability, but that doesn't matter since those were abandoned in the 60's or 70's.
6.) Another poster addressed the myth that the shuttle has to be rebuilt from the ground up, but I'll repeat it since the myth seems to come up incessantly. The shuttle is thoroughly cleaned and inspected, any repairs or maintenance needed is performed, damaged tiles replaced, and the engines tested. The solid rocket boosters are refurbished and reloaded, and a new external tank is fitted. This is most definitely not a rebuild.
7.) The arguments versus the shuttle are somewhat irrelevant since the ISS components were mostly designed around the shuttle cargo bay and with the shuttle's capability as a work platform in mind. Additionally, the limiting factor on many of the payloads has been not mass, but crew hours available to install them and launcher volume. And don't forget, the launch capacity of the Saturn V is before crew accomodations. For the shuttle, it's after.
8.) The discussion here was a Mars mission, and NASA is developing a more advanced launcher that would eventually contribute to that purpose. The Ares V will have a 130 mT LEO capability, compared to 118 mT for the Saturn V. NASA hasn't made a lot of cost projections, but looking at the infrastructure required and the types of components being used, I'm guessing the Ares V will be around $500-750 million per launch, not counting development costs. I'd figure $150-250 million for manned Ares I missions.
No, that's with the fixed costs of extending the program apportioned. Sorry, I don't remember where my original source for this was, but I'm pretty certain on this point. The sub $100 million figure is just the costs of reprocessing the orbiter and conducting the launch. That does not, however, include initial investment in design and infrastructure, and a bunch of similar miscellaneous costs like the return-to-flight work, which inflate the number further to about $1.3 billion per flight.
NASA is considering adding two more missions to the manifest for early 2011, and I think they're looking at around half a billion as the estimated cost to the shuttle program, not counting the payload, which I believe comes out of the ISS budget.
Also, the $100 million figure for a Saturn V quoted further up in the discussion is bogus, except perhaps in ~1970 dollars. NASA spent $6.5 billion on the Saturn V program from 1964 to 1973 and conducted 13 launches, three of them unmanned. That's $500 million per launch not adjusted for inflation.
You can darn well bet that a Saturn V would cost over $100 million today. The Delta IV heavy, a more modern but much smaller rocket costs over $200 million per launch. The similar-sized but older Titan IV costs about $250 million per launch, which is why it was retired. Even SpaceX's Falcon 9 Heavy, also about the size of the Delta IV, is expected to cost $90 million, raising serious skepticism from many in the launch services industry because the proposed number is so much cheaper than anything in its class.
First of all, I wanted to question whether anybody knew if they had any customers for this satellite bus? The two photos looked more like non-flight testbeds than shiny, thermally controlled satellites we're used to seeing.
Second, does anyone know if a magnetic orientation system has been used on any satellites in the past? Obviously, the rotation rates that can can be achieved by such a system must be pretty low, especially if the satellite has no moving parts to extend booms, so I'm curious what sort of payloads this bus is useful for.
Third, one of my first thoughts is it sounds like they might be specifically targeting themselves at SpaceX. With the 1400 pound LEO capacity of the Falcon 1 for $8 million, it's the only rocket that could put one of these things (perhaps two) into space for the $10 million estimated in the article. Even the current low cost contender in the US, the Orbital Sciences Minotaur, which reuses SRB's from retired Peacekeeper missiles, costs over $12 million per rocket, not counting payload integration and launch, as I understand it.
Lastly, the article says this satellite would be a competitor with the Falcon 1, which is obviously false. The Falcon 1 is a launch vehicle. FASTSAT is a satellite. They go together, not compete.
Mars Rover and MER in your response are the same thing. The Space.com article is very out of date, and they had some cost overruns after that which pushed the mission to $820 million, which included I believe the first year of operations and science. I believe NASA has spent another couple hundred million on operations and science due to the extensions...a lot of money, but a lot less than equivalent new missions.
Also, the Mars Science Laboratory currently being built for a launch in 2009 is looking to cost around $1.8 billion USD (a little over a billion Euros, IIRC). It will be nuclear-powered, land completely ready to go instead of in those nifty airbags the MER's came in on, and is roughly the size of a Volkswagen (which is why the airbags won't work). It's supposed to last about 2 years, so if it runs the way the MER's have, NASA will still be trying to kill it off 20 years from now (just kidding...that's ridiculously unlikely).
MSL also ran into budget issues, and has increased in cost several times over the last couple of years, so NASA recently cancelled two rather fascinating instruments to keep the cost down. The first was the descent imager, which I'm not sure how much scientific value it would've had, but the time-lapse video of the descent would have been fascinating. The other was the ChemCam, a marvelous laser and spectrometer combo that would allow scientists to analyze the chemical composition of rocks from up to 40 feet away. However, the descent imager on the Mars Phoenix Lander currently en route turned out to have a fatal flaw, so the operations budget for that got switched to the construction budget for the MSL. Also, the Chemcam team realized that it had come down to defeaturing the Chemcam or not flying it all, and went with the former option to get back in budget. They got some extra money that was saved because Mars Phoenix launched on time. Unfortunately, the sweet zoom capability of the mast camera was cut out and not re-instated.
The CIA world fact book says 2004 electrical production (not counting transportation energy, etc) was 17.4 trillion kW-hours, so we'd need at least 2 TerraWatts of capacity. A relatively large nuclear reactor produces about a GW of electricity, which translates to 2000 plants. Add in other energy needs currently met by fossil fuels and account for capacity factors and that CalTech professor you reference is probably within an order of magnitude of the actual need.
The problem with that argument is it only demonstrates the scope of our energy needs. It says nothing about the feasibility of nuclear versus other technologies, and ignores the fact that the exact same challenge applies to any energy source. To cover our needs with just coal (currently 25% of the world energy supply and something like half of the electrical supply) would similarly require about 10,000 coal plants. You want to it with wind? You need roughly one million of today's highest capacity wind turbines. Solar? About $20 trillion dollars worth of solar panels near the equator will do it. Hydro? Well...forget about that one. Hydro power options are mostly in use in developed countries.
We'd run out of nuclear fuel in decades (actually, I've been told centuries) if we continued to utilize it as poorly as we currently do. Reprocessing, however, can dramatically increase the available energy from existing fuel and potentially the economics of developing new mines. Not to mention reducing the waste by 90% or so.
Don't forget we're just talking about nuclear fission here. If we can get fusion working commercially, the picture changes.
Anyone who thinks we'll get all our energy from one source in the foreseeable future, however, is out of the loop.
The HD camera on SELENE is a PR instrument. Video is useful for things that change. The moon, for the most part, does not change, and the HD camera does not produce scientifically useful images of the moon. SELENE can only take about a minute worth of video.
High Definition as a proper noun generally refers to 1920x1080 resolution, but the various space agencies have produced much higher resolution images for years. The 35mm film shot during the Apollo missions is being scanned into 3070x2044 pixel images, for example, and the medium format film is being scanned at a huge 12800x12800 pixels. The Mars rovers carry 1 MP (1024 x 1024) cameras, and the images are often stitched together into far larger mosaics. I've seen some that even as JPG's take up over 100 MB (and crash IE). The Hubble Space Telescope's highest resolution camera is also only 1024x1024 pixels, and I believe this was chosen to approximate the maximum resolution of the optics, but again, large mosaics are common.
The High Resolution Imaging Scientific Experiment (HiRISE) camera aboard the Mars Reconnaisance Orbiter takes a different approach and is what's called a "push broom camera." Instead of taking rectangular pictures every so often, it scans a single line of up to 20,000 pixels continuously at the rate the spacecraft moves over the ground. In this way it builds up images up to 40,000 pixels long (800 megapixels...now that's high def!), at which point the file has to be transmitted to earth or the camera runs out of memory.
It sounds like you've read Tom Clancy's Submarine. It sometimes amazes me what military personel will tell him anonymously.
Every indication I've seen is that this is a true story. The ship was the USS Enterprise, our first nuclear-powered carrier. The tail was a Soviet November class submarine, one of their early nuclear-power attack boats. They were surprised to find it chasing them at 30 knots, an ability that was later explained by saving weight on reactor shielding (The running joke is that Soviet sub crews glow in the dark). It was probably equally as surprising that the sub could track the carrier while making so much noise itself, much less maintain that speed. The problem wasn't that the Enterprise had reached its top speed, but that her combustion-powered escorts had.
The captain of the sub may not have known he was being tracked (helicopters using sonar buoys are pretty discrete, and surface ships have an even worse time hearing over their own din than submarines, something the Russian captain would have known), while the Americans could bet the Russians knew the Enterprise could easily reach those speeds with plenty of power to spare.
This Chinese sub popping up within range of a battle group (modern torpedoes have a range more than twice that, although by running flat out away they might still have been escaped damage) isn't a show of stealth or technology so much as it is of cleverness and planning. Electric boats are not very fast, but they're darn quiet, even older designs. If the captain can successfully guess its course, which might not be very hard absent a reason to zig zag, he just has to make a dash to get in its path while it's still distant, then manuever at a silent crawl to exactly where he wants to be. It can literally be quieter than the water around it. So all they're really telling us by sneaking into the middle of a battle group is that they have sub drivers with the guts and smarts to do so.
And of course it's also possible, as suggested, the sub found itself there inadvertantly and surfaced to avoid any misinterpretation of hostile intent.
If you're up for a reading recommendation, Larry Bonds does an excellent job of portraying this dash-and-wait tactic for a chapter of Red Phoenix. Or there is the riveting real-life account of the sinking of the largest Japanese carrier in WWII in Shinano!
Yes. Something that is easy for us to forget is that they didn't have roads, or even much in the way of all terrain vehicles, much less helicopters or satellites when this occurred. Not to mention, it was largely ignored until after the revolution and WWI were both finished up with. The first aerial photographs taken of the site were taken 30 years later and still clearly showed the fall pattern, but no crater was visible.
It's easy to look at the pictures and think you can simply follow the trees all the way to the center. Way easier said than done. First of all, the site is pretty much in the middle of nowhere. There's just a few scattered villages, no doubt with abysmal roads between each and almost nothing traversable with wheels leading anywhere else. They would have walked or ridden pack animals for the entire survey.
It's also a huge area. 80 million trees were felled over 830 square miles. Hunters (I've done my share) and loggers are probably familiar with trying to walk through such an area. The trees may look all neatly arrayed in a photograph, as if you could step easily from one to the next or walk between them like a trail, but the truth is far different. Without the perspective benefit from being atop a hill, the fall pattern is more difficult to discern. The branches will lie tangled, blocking the path at frequent intervals. The trunks will be random distances apart, some managing to overlap nearby trunks. They often sit several feet above the ground, making it easy to fall and twist an ankle or knee, and exhausting to climb over again and again and again. Vegetation will have sprouted up in the 19 years between the fall and Kulik's arrival, leaving a tangled mess of shrubs and briers that sometimes appear deceptively solid from above and forboding from ground level. A mile per hour is a decent speed walking through such an area with several days worth of supplies on your back.
But Kulik actually did push through to the center, and he found several trees standing upright, stripped of their branches, consistent with an airburst from above. He also found a bog he was convinced was a crater, but when he drained it there were old tree stumps at the bottom. For an impact to have formed the bog the blast would have shattered the old trees and tossed the remains out of the muddy crater.
Oops...yes, that should have been 0.035% of the helium on the moon is He-3 and 0.000138% of helium on earth is He-3. Not only did I copy the same number down twice, I misplaced a decimal point.
As I understand it, the difference is because most of the He-3 on the earth is primordial...from the earth's formation. He-3 from the sun also strikes the earth, but is quickly lost again from the upper atmosphere. On the moon, there is primordial He-3 plus new stuff from the sun that gets trapped in the rock since there is effectively no atmosphere to slow it down before encountering the surface.
The dilution of He-3 on earth is also increased due to radioactive decay producing alpha particles (He-4).