Domain: usra.edu
Stories and comments across the archive that link to usra.edu.
Comments · 257
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Disappointed?You may have noticed the extremely low resolution of the images produced by Chandra. In fact, other craft have gotten much better pictures of elemental compositions of the lunar surface, especially common elements like titanium and iron. For instance, Galileo returned this and Clementine (some very high res images here) returned this iron map and this titanium map.
Chandra detected magnesium, silicon, aluminum, and oxygen, but its already known that the lunar highlands are composed mostly of anorthosite, a rock which contains all of those elements but magnesium (I would like to know why magnesium and not calcium was detected). This is more of a proof-of-concept than anything. The most important information to come from these first observations is the discounting of the anomolous farside x-ray emissions.
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Re:Communications potential of space probes?The design data rate for Galileo with the high-gain antenna was 134 kiloBIT per second. The NYer fact checkers missed the 8x larger claim for 134kbyte/s rate in the article
:-)
For the more semi-technical details see this article
Most NASA PR contained the following paragraph:
Galileo's high-gain antenna was to have provided a 134- kilobit-per-second real-time data rate from Jupiter. Had no improvements been made in the Deep Space Network, only a 10-bit per second data rate would have been possible with Galileo's small low-gain antenna for most of the mission. With these improvements, however, along with the changes made on the spacecraft, further increase the downlinked data to an effective rate of 1,000 bits per second.
RTF New Yorker article for the full story of the software effort that saved Galileo. -
Re:www.highliftsystems.comYour NIAC URLs were a bit garbled.
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Re:www.highliftsystems.comYour NIAC URLs were a bit garbled.
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Re:Digital Cameras in freezers on rockets.
Indeed; SIRTF will be great in the short term, but for real longevity (including upgrades to the instrumentation as technology advances), it's going to be hard to beat SOFIA. The ability to service and upgrade a facility is what kept HST useful for so long. With SOFIA, we're effectively dealing with an observatory that lands every day. By comparison with space based observatories, improving and upgrading SOFIA will be a snap!
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Re:Liitle green snowmen (really!)
Yes "snowmen" would be very interesting indeed.
This image and this corresponding daytime image (you can search through all of the THEMIS images from the mars odyssey probe here) show strange and as yet unexplained thermal anomalies on the surface(see here to put the images in context). This is really REALLY important since this is so far the only place on the surface that seems to be emitting heat of a geothermal(ie. not heat from absorbed sunlight) origin. These sites NEED to be imaged by the high resolution camera on MGS as soon as possible to find out wheather they are steaming ice towers or 'fumaroles'(likely due to the huge amount of water ice just discovered under the surface) of the kind found on earth or not. If they are, they are the most promising candidate for life to exist on the surface found to date. -
My Required Space Elevator Post
It's a pet project of mine, but I think it bears commenting on: The space elevator.
I think it may be a _very_ good option for the nation's space needs.
More information can be found here:
Space Elevators: Low Cost Ticket to GEO?
More on Space Elevators
Going Up?
Calling the Space Elevator
Space Elevator May Become Reality - The Linked Study(PDF) Was fascinating.
Space Elevator Could Cost Less Than You Thought
Stepping Closer To The Space Elevator
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This is why we need manned missions...
Unless you buy into the notion that all the Mars probe failures were due to xenophobic Martians, we've recently witnessed several examples of unmanned, robotic craft turning into expensive piles of junk for reasons ranging from the sublime (legs bounced harder than expected) to the ridiculous (meters? feet? what's the difference?).
Contrast those catastrophic failures with events on human-occupied craft. Fires and collisions on Mir, and of course Apollo 13 for those who get their science from the local multiplex -- yet the craft kept flying, due to human involvement and ingenuity. The conclusion is clear: the more complex the system, the more likely you need a non-silicon-based intelligence to keep it from self-destructing.
To address the issue at hand: NASA wants to send a nuclear-powered spaceship to Jupiter? Cool, but you'd darned well better include a crew compartment, unless you *want* to see what happens during a space-based meltdown.
The bottom line is that there is no way to predict everything that can go wrong with any complex system. That's why we need more manned missions. Spend less money on absolutely "perfect" systems, and more on systems to support a human presence to fix it when it breaks.
After all, Captain Cook explored the south Pacific with nothing more than boats of wood, and men of iron. He also had a whip, and generous quantities of very strong beer... -
Nasa's Spin...
..."Saddam Hussein is alive and well in a bunker on the moon, Mr. President."
Polar Night? It sounds like Nasa's been playing with the Military Operation Name Generator. -
PDF of this research
For anyone that is exterested, there is an extended scientific abstract of this work, here, to be presented as a poster on Thursday evening at the Lunar and Planetary Science Conference in Houston, Texas. This is a serious conference (I'll be there as usual), and so we'll soon see whether this stands up to scientific scrutiny.
Having read the abstract, and work by Mike Malin (PI of the camera on Mars Global Surveyor) and co-authors, who proposed that these features were water some time ago, I think that there still needs to be more work (and more importantly, supporting evidence, e.g. spectral) before there will be a concensus that the streaks are indeed caused by water. However, the fact that there is clearly a change means that, if these are caused by water, then they are certainly VERY recent (i.e. a few years), which has profound implications. The question would then need to be asked, is the water flow due to an active hydrological system caused by climatic and orbital change, or is it related to volcanic/hydrothermal processes? The latter seems unlikely as there is no evidence, to my mind, of an unusual thermal anomaly in the vicinity of Olympus Mons. Also, there are streaks like this in many other areas of Mars. However, it may be possible to set up a hydrothermal system without an easily detectable thermal anomaly - I don't know for sure. I'll try to ask the author what she thinks next week.
-Karl
Dr Karl Mitchell, Planetary Scientist, Lancaster University, U.K. -
Re:Current Data: Inconclusive
I agree. This headline is definitely jumping the gun, which is beneath what I usually expect of the BBC. Clearly that there is change on the surface is interesting. However, there are alternative explanations to water, such as a debris flow, due to slope collapse, exposing materials in a different oxidation state, which need further investigation.
This is also research that has, to my knowledge, not been peer-reviewed. Tahirih Motazedian is a planetary scientist that I have never met or heard of before. I think she is a student or a junior RA, not that that means anything in itself. It certainly must have taken some degree of dedication to sift through all of the overlapping images to look for such change, and that should be applauded.
This work is being presented at the Lunar and Planetary Science Conference in Houston next week (click here for an abstract), and so we'll soon see if it bears up to scrutiny (I'll be there). At a first glance, the abstract seems to make perfect sense, but it would need some sort of supporting evidence (possibly using multi-spectral THEMIS data) before convincing me. -Karl
Dr Karl Mitchell, Planetary Scientist, Lancaster University, U.K. -
Lack of Imagination?
I'm appalled at the lack of imagination shown by most of these posts.
First off if you read the PDF (15M) report to Nasa prepared by Bradley C. Edwards to satisfy the requirements of his $500 000 grant you will readily see that this is totally feasible.
Next check out the website - where they are calling for people to express interest in working on this project. They expect to be hiring in the next year or so. You'll also see that serious people are taking this seriously. Do you want a job?
Next understand that $17B is not very much money. Considering that BP just spent $6.7B on a oil company in Russia and has plans for more purchases.
I meantion BP because they have a plan to move beyond oil.... BP Solar is BP's attempt to become a broader energy company (check out their new sun logo) instead of an oil company. The High Lift systems news page says: -
BP Solar - a subsidiary of British Petroleum, currently doing $300M in annual sales. Our discussions have focused on BP's interest in using the SE for deployment of a solar energy satellite. Several items that came up included possible collaborative efforts, the performance of our system and the possibility of BP using our system. They are considering writing a letter of endorsement
If BP with the cash they have can throw $6.75 B at Russia they could, over 5 years, finance a large share of the Space Elevator. Who needs the Government? In fact Nasa would make sure it costs more to build than it should. Nasa is a bureaucracy, not a business, and is ill-suited to the sort of cost control required of economically viable business decision. Only communists would argue that a Space Elevator should be built and controlled by government.
What would BP Solar do? Build Power Sats....
These are High Lift's vision for the main use for the Space Elevator. Imagine a fleet of these beaming power to anywhere on earth. Every country on the planet could get cheap electricity without the huge national grid infrastructure required now. Without the huge investments in time and resources to build power stations - and without the fossil fuel use.
Use your imagination.
These ideas have been the subject of SF for decades - but the Space Elevator is now possible due to those nifty Carbon Nano-tubes.
When your imagination focussed by the reality of this thing actually being built in the near term (5 years) everything changes - and it'll change for us not our children. It'll change our careers.
Imagine this - an electric airplane that is powered by a Powersat beaming microwaves to it. No fuel to carry, super efficient travel - and at what speeds?
These guys are planning for the Space Elevator to be operational SOON - they have realistic timelines.
What I want to see here is some discussion of the uses that could realistically be made of a space elevator. We're the generation that will built it, use it and be changed by it. I like the parallel to be made with electricity, or flight, or the steam engine - in the early stages everyone probably dismissed it - and the world changed despite them.
What would you realistically (with a nod towards economic viability) do with the low launch costs they're projecting - $10/LB...
Ideas anyone? -
Lack of Imagination?
I'm appalled at the lack of imagination shown by most of these posts.
First off if you read the PDF (15M) report to Nasa prepared by Bradley C. Edwards to satisfy the requirements of his $500 000 grant you will readily see that this is totally feasible.
Next check out the website - where they are calling for people to express interest in working on this project. They expect to be hiring in the next year or so. You'll also see that serious people are taking this seriously. Do you want a job?
Next understand that $17B is not very much money. Considering that BP just spent $6.7B on a oil company in Russia and has plans for more purchases.
I meantion BP because they have a plan to move beyond oil.... BP Solar is BP's attempt to become a broader energy company (check out their new sun logo) instead of an oil company. The High Lift systems news page says: -
BP Solar - a subsidiary of British Petroleum, currently doing $300M in annual sales. Our discussions have focused on BP's interest in using the SE for deployment of a solar energy satellite. Several items that came up included possible collaborative efforts, the performance of our system and the possibility of BP using our system. They are considering writing a letter of endorsement
If BP with the cash they have can throw $6.75 B at Russia they could, over 5 years, finance a large share of the Space Elevator. Who needs the Government? In fact Nasa would make sure it costs more to build than it should. Nasa is a bureaucracy, not a business, and is ill-suited to the sort of cost control required of economically viable business decision. Only communists would argue that a Space Elevator should be built and controlled by government.
What would BP Solar do? Build Power Sats....
These are High Lift's vision for the main use for the Space Elevator. Imagine a fleet of these beaming power to anywhere on earth. Every country on the planet could get cheap electricity without the huge national grid infrastructure required now. Without the huge investments in time and resources to build power stations - and without the fossil fuel use.
Use your imagination.
These ideas have been the subject of SF for decades - but the Space Elevator is now possible due to those nifty Carbon Nano-tubes.
When your imagination focussed by the reality of this thing actually being built in the near term (5 years) everything changes - and it'll change for us not our children. It'll change our careers.
Imagine this - an electric airplane that is powered by a Powersat beaming microwaves to it. No fuel to carry, super efficient travel - and at what speeds?
These guys are planning for the Space Elevator to be operational SOON - they have realistic timelines.
What I want to see here is some discussion of the uses that could realistically be made of a space elevator. We're the generation that will built it, use it and be changed by it. I like the parallel to be made with electricity, or flight, or the steam engine - in the early stages everyone probably dismissed it - and the world changed despite them.
What would you realistically (with a nod towards economic viability) do with the low launch costs they're projecting - $10/LB...
Ideas anyone? -
Re:Okay
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Re:What I'd like to seeI'd also like to see a space elevator persued, but I don't know that we have the tech yet.
Here's a good paper on the subject. It's a 15mb pdf, but worth the download.
In it, a good many of the technical problems are solidly examined, and reasonable solutions are proposed.
The approach presented is to launch an initial spool of very thin cable into geosynchronous orbit. This spool will be some thousands of kg in mass; this won't be *that* much harder than putting up a communications satellite. Then you lower that cable down to earth (and raise spool-unreeling spacecraft up past geosynch. as a counterweight), and you have a sort of "mini" space elevator that can haul up a mere 1200 kg. A series of climbers then ascend, each epoxying on a new layer of cable. Continue for 2 years, and you have a cable that can carry up as much as the shuttle. Continue for 5 years, and you have one that can lift a million kg.
All the solutions to the technical problems will require lots of research/testing to truly overcome, so it'd likely still be decades away, even with full effort. And that's also assuming the cable itself can be built.
I think that's the paper's main weakness, actually: its reliance on finding an epoxy to construct the cable with, that will allow the overall cable strength to be similar to the inherent nanotube strength. The proposal calls for 3-cm lengths of carbon nanotube to be assembled into the cable (in a mostly flat ribbon shape) with the epoxy. This is because such lengths of carbon nanotubes have indeed been produced, and the paper is trying to go with known technology as much as possible.
Now it seems to me that finding an epoxy strong enough to hold on to the fibers would require finding a substance with nearly as much strength as the fibers themselves. Otherwise, the epoxy will fail when the load becomes great, and the fibers will just slip out. A strong rope does you no good if you can't hold onto it!
Though perhaps there's something about epoxying materials from fibers that I don't understand. Anyone? Anyone? Bueller?
The terrorist-threat angle is another concern. Though a terrorist attack would presumably occur at the low end of the cable, which would have minimal effect on the earth.
The main environmental risk is that of the cable breaking at a high point, possibly at the counterweight. The paper say that if this happens, "About 3000 kg of 2 square millimeter cross-section cable
... may fall to Earth intact and east of the anchor." It goes onto say that further study/simulation is necessary to determine the full threat.
So again, for me, I'm not so sure that the epoxy technique of cable construction will work. We may have to wait until we have enough nano-scale control to be able to construct the cable with full-cable-length nanotube, finely interwoven. Of course, once we can make nanotubes like that, a lot of other possibilities for space travel may open up. -
Re:Only a space elevator makes true sense
Bob Munck makes all the points I was going to make, so I'm not going to rehash them, but check out this site for the first chapter or the complete, 15 MB NASA report, telling you just how fast, cheap, easy to build it would be. Trillions of dollars my arse, get better informed before you try and pick apart someone's arguments.
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Re:Enough already
Here are a bunch of details.
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Previous Space Elevator Coverage
I think that the Space Elevator is a really good idea, and there have been some very interesting(and detailed) studies of the feasibility.
Previous Articles:
Space Elevators: Low Cost Ticket to GEO?
More on Space Elevators
Going Up?
Calling the Space Elevator
Space Elevator May Become Reality - The Linked Study(PDF) Was fascinating.
Space Elevator Could Cost Less Than You Thought
Stepping Closer To The Space Elevator
I want to walk into an elevator some day and see two buttons - "G" and "O". -
Why not the space elevator?
Since the Columbia tragedy, I have also wondered which direction NASA should take with future missions. In the course of my investigation, I found this paper, commissioned by the NASA Institute for Advanced Concepts in 2000, that claims that a space elevator is not only technologically feasible, but is possible to build within the next 15-20 years at a cost of approximately $40 billion US dollars. This would be a tremendous project, but on the same scale as other large American engineering feats.
It seems that such a promising technology, which would not only decrease launch costs by orders of magnitude but also result in many 'spin-off' technologies, would be at the top of NASA's list of research topics. However, I can find no evidence that NASA has pursued the idea since. I am not advocating that we start building a space elevator tomorrow; however, I think it would be horrible for NASA to shelve a radical but potentially remarkable invention for another 50 years. How can we encourage NASA to, at the very least, begin a second round of research to independently and skeptically study the results of the first team and put together a plan to actually build this, if possible? Or is the American space program doomed to another 50 years of risky and minimally rewarding shuttle flights? -
Additional Landsat images
What a nice project, to correlate (which does not prove causation*) ground and orbital studies. It must have been difficult -- which suggests skills acquired for future challenges.
On the more aesthetic side, "Earth as Art" is just starting out, but very encouraging.
USGS has done a Landsat study of environmental change and NASA's general collection.
Wasn't it Al Gore who proposed a live video feed from a satellite watching Earth. Please don't share your opinion on Gore or the cost -- but wouldn't that be a nice little channel to have? I could name about 20 cable channels I'd surrender to get it (small loss). You could be one of the first to detect the first nuclear conflict. See, I'm not all that optimistic.
And linked from my home page is the Earth Science Image of the Day with explanations.
There are a lot of amazing photos out there, I am always interested in hearing of more, especially if explicated. I'm glad to see them coming to increasingly creative use, beyond assessing crops and measuring ocean temperatures -- useful as these things are!
*semi-inside joke -
Slashdotted.Here is the text I was able to get:
Research Project Funded by the NASA Institute for Advanced Concepts
Principal Investigator
Anthony J. Marchese, Ph.D.
Associate Professor
Department of Mechanical Engineering
College of Engineering
Rowan University
201 Mullica Hill Road
Glassboro, NJ 08028-1701Office: 235 Rowan Hall
Email address: marchese@rowan.edu
Telephone: (856) 256-5343
Fax: (856) 256-5241Project Summary
During the past decade, several research groups have begun to report unique spectroscopic results for mixed gas plasma systems in which one of the species present was hydrogen gas. In these experiments, researchers have reported excessive line broadening of H emission lines and peculiar non-Boltzmann population of excited states. The hydrogen line broadening in most of these studies was attributed to Doppler broadening associated with high random translational velocity of H atoms (i.e. "fast hydrogen").
Recent data have been published by scientists at BlackLight Power reporting similar phenomena that suggests the presence of a newly identified regime of energetic mixed gas hydrogen plasma systems. Specifically, the following phenomena have been reported:
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Preferential Doppler line broadening of atomic hydrogen emission spectra,
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Inverted populations of hydrogen Balmer series in microwave hydrogen gas mixture plasmas,
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Novel vacuum ultraviolet (VUV) vibration spectra of hydrogen mixture plasmas, an
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Water bath calorimeter experiments interpreted as showing increased heat generation in certain gas mixtures.
Scientists at BlackLight Power, Inc. have explained the above phenomena based on a hypothesis that, under certain conditions, hydrogen atoms can undergo transitions to energy levels corresponding to fractional principal quantum numbers. However, since the theoretical explanation of the BlackLight Process has entailed a reworking of quantum mechanics, the theory has not been readily accepted in the scientific community. Regardless of the theoretical explanation, the experimental data suggests that these plasma systems have unique characteristics that warrant further exploration for propulsion applications.
Accordingly, the objective of the recently completed NIAC Phase I study was to assess the potential of low pressure, mixed gas hydrogen plasmas toward the development of high performance space propulsion systems. The project was awarded to Rowan by the NASA Institute for Advanced Concepts in April 2002. Prior to the Phase I study, no attempt had been made to apply this type of plasma system toward the development of a rocket thruster. Preliminary calculations suggest that such a thruster could achieve performance several orders of magnitude greater than chemical rocket propulsion.
During the period of May 1, 2002 to November 30, 2002, the following progress was made on the project:
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Conceptual designs for two separate proof-of-concept thrusters were completed.
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Configuration designs for thruster hardware were developed using SolidWorks 3D solids modeling.
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A BlackLight Plasma Thruster (BLPT) was fabricated.
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A BlackLight Microwave Plasma Thruster (BLMPT) was fabricated.
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An experimental vacuum test chamber apparatus was developed for testing the BLPT and BLMPT thrusters.
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A spectroscopic technique was developed for measuring thruster exhaust velocity using a Doppler shift of hydrogen emission spectra.
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A 1 kW class arcjet thruster and power supply was obtained from NASA Glenn Research Center to benchmark Doppler shift velocity measurement technique.
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Experiments on the BlackLight process were performed including:
o Thermal characterization of a compound hollow cathode glow discharge apparatus,
o Hydrogen line broadening measurements in low pressure microwave water plasmas,
o Measurements of inversion of line intensities in hydrogen Balmer series,
o Measurements of novel vacuum ultraviolet (VUV) vibration spectra of hydrogen mixture plasma, and
o Water bath calorimetry experiments.
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The BLPT and BLMPT were installed into vacuum systems and successfully test fired.
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Preliminary experiments were performed to measure emission spectra of the exhaust gases of the BLMPT thruster.
Each of these results is described in the Phase I final report, which was issued on Dec. 2, 2002.
The following presentation was given at the NASA Instituted for Advanced Concepts Phase I Fellows Meeting in Atlanta, GA on October 25, 2002. Download presentation here.
Rowan Project Personnel
Anthony Marchese, PI
John Schmalzel, Co-PI
Peter Jansson, Co-PI
Mike Muhlbaier, student
Kevin Garrison, student
Jennifer Demetrio, student
Tom Smith, student
Mike Resciniti, '02 (Graduated. Now at University of Michigan.)
Test Firing BLMPT Thruster
Last updated: Dec 4, 2002
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Re:That's not important
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Re:That's not important
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Space Elevator
What about the space elevator? I think that it is a really good idea, and there have been some very interesting(and detailed) studies of the feasibility.
Previous Articles:
Space Elevators: Low Cost Ticket to GEO?
More on Space Elevators
Going Up?
Calling the Space Elevator
Space Elevator May Become Reality - The Linked Study(PDF) Was fascinating.
Space Elevator Could Cost Less Than You Thought
Stepping Closer To The Space Elevator
I want to walk into an elevator some day and see too buttons - "G" and "O".
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Advanced Concepts and ISSSo what will happen with the funding of NASA's Advanced Concepts branch? As I read the article (2 long pages) and saw that they were basically COMPLETELY scrapping everything from the X-33, I was hoping to see that they might start pumping more money into the space elevator. But I was left disappointed; they decide to go with strapping a plane onto a rocket... which is what they've been doing for a long time already.
:( Also, from what I read, it sounded like NASA is planning on letting other countries finish the station on their own.This resulted in identifying a stage in the development of the ISS - U.S. Core Complete wherein all developmental focus should lie. U.S. Core Complete is the point at which assembly has proceeded so as to facilitate the addition of all modules and hardware being provided by the ISS program's international partners. This would result, however, in a space station with only three crew (since the crew return vehicle had been eliminated from development) and a limited ability to do science.
Uh... what's the point of building the huge, expensive station, if we're not going to be able to put more than 3 people up there and only do a small amount of experiments?? Or am I reading this wrong? very confused...
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Re:Why don't they...They left mirrors up there so that people could bounce lasers off them.
;)It lets us calculate the distance from the Earth to the Moon.
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Re:Why don't they...
To measure distance.
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Re:A moon landing believer who also doubtsHOWEVER, I have seen the evidence that the moon landing skeptics have provided and some of it is damn compelling and yet to be answered by NASA.
Compelling only if you have your head so far up your ass you've lost contact with the real world. The evidence is total crap. If I felt like blowing a chunk of my own personal budget I could bounce a laser off of one of the mirrors they put there. Where is your "damn compelling" evidence monkey boy?
$15,000 is a small price to pay if thet actually answer convincingly the questions and compelling "wholes" presented by the moon hoax crowd.
That's $15,000 that I paid a percentage of to try to convince brain damaged twits that we really did land on the moon. That's $15,000 more that could be spent getting data off of Galileo's flyby of Amalthea -
Re:FOX Network
There was also a recent article in Discovery magazine mentioning this bad-science-blundering. They provided the link to bad astronomy and mentioned some of the other urban-legends-of-science like being able to balance an egg during the equinox. One of the points they presented was how scientists do some experiments with bouncing laser beams off a mirror on the moon which the Apollo astronauts placed there. How's that for not landing on the moon?! Check it out some details here
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Really good NASA article
Here's a nice sized (15MB) report done by NASA. They talk about all sorts of problems that need to be worked out to make get this project off the ground http://www.niac.usra.edu/files/studies/final_repo
r t/pdf/472Edwards.pdf -
USERS experiments
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The original NIAC paper
This idea originally came from NASA's institute for advanced concepts.
There are a lot of funky stuff going on there. But, here's the original space elevator paper. I personally thought it was an interesting read. -
The original NIAC paper
This idea originally came from NASA's institute for advanced concepts.
There are a lot of funky stuff going on there. But, here's the original space elevator paper. I personally thought it was an interesting read. -
Nitpick
Carbon nanotubes have become a hot item of discussion across all fields of engineering because, in part, the cylinders constructed from hexagonal links of carbon atoms are believed to be perhaps the strongest manmade material.
That should be "strongest material fullstop". The inference to natural materials can only be referring to spider silk. Spider dragline silk has a tensile strength comparable to steel, but will stretch 35% without breaking. It seems steel can achieve up to about 5 Gpa in tensile strength depending on quality, etc. Carbon nanotube fibres are expected to be in the hundreds of Gpa.
There is a cautious belief amongst materials scientists that carbon nanotubes may in fact be the strongest substance possible in terms of tensile strength.
A great overview of nanotubes as a construction material can be found in Bradley Edward's Space Elevator manuscript. See also the slashdot discussion about it. -
International Space Development ConferenceHaving just returned from the National Space Society's 2002 ISDC meeting in Denver, I've had a crash course in space law... The conference chair this year, Wayne White, is assistant director of the space law and remote sensing institute in Mississippi, and an entire day of the conference was devoted to these issues.
From what I learned, there is a large body of national and international law about space that rests on this treaty and a few others (space liability, rescue and return, etc.) and throwing this one out is unlikely. But, these treaties do have a fundamental problem in not providing any mechanism for private property rights in space, nor particularly envisioning any sort of settlement process. There are a large number of ideas for how to fix this - Alan Wasser's proposals mentioned in the article are one of them. There's also Declan O'Donnell's United Societies in Space that advocates extending common law rules to outer space, and of course there's the Lunar Embassy that's taking advantage of the current ambiguities to sell property on the Moon and other bodies.
What's needed is a push from the US State Department to get these things resolved - there are apparently individuals there who would know what to do to get a new treaty worked out or current treaties amended, but there's been absolutely no support from higher up for it. Write your congressmen or directly to the State Dept. to express your views if you feel a legal property regime for outer space is important! -
Re:Angular momentum
Yes, finally nested 6 or 7 deep the correct and simple answer to the question. The angular momentum comes from the Earth.
As a payload climbs the cable its angular momentum is increasing. This is initially transferred to the cable which may or may not pendulate. However since the cable is pulling upwards under centripetal acceleration, it will eventually transfer its extra angular momentum to the Earth.
I don't agree however that you could cancel the effect out by timing the subsequent launches. The issue of total angular momentum needs to be addressed. Subsequent launches could only cancel the angular momentum if they were somehow launched from the end of the cable with opposite angular momentum.
We can consider the total angular momentum to be a conserved scalar (keep everything moving around the Earth's axis). As a payload climbs the cable its angular momentum is increasing. Consequently the angular momentum of the cable is decreasing, so it lags behind the Earth (very very slightly). Having just read the full 15Mb document, I don't think was discussed anywhere. My guess is that the cable would lean very slightly to the west more or less permanently while you are sending up payloads. In this state the cable would also be pulling up and to the west on the mooring station, which would bleed off some angular momentum from the Earth (but never enough to measure). If you stopped sending up payloads the cable would gradually straighten. I'm not 100% sure how the converse case works (when payloads come down the cable). But one thing discussed in the thesis is how gravity applies a torque to the cable when it is not perfectly vertical. In this case an equal and opposite torque is applied to the Earth through gravity. -
the paper, not the slides
That 8M download only gives you the slides - pretty pictures but no text. The actual phase I paper is here. It's a 15M download - and you can year the server creaking under the strain.
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Re:Usefulness?
How about better control for computerized surgery and other medical procedures?
Mapping, and lots of different kinds of aerial/satellite photo analysis. You don't have to be looking directly at something to see a 3D view of it--you can look at stereo images--and so could a computer. Examples at Lunar and Planetary Institute: 3D Mars images.
Eventually, autopilots for cars. -
Re:Why bother?
>Not to mention the fact that one side of the
>moon faces the sun at all times! Any solar
>collectors on Earth are subject to day/night
>cycles. The moon would rarely be impacted, when
>the lunar eclipses happen.
Doh! One side of the moon always faces the EARTH! (synchronous rotation). We had never seen the far side of the moon until we sent something "back there" to take pictures.
So: that being the case, is it really possible that one side of the moon is always bathed in the light of the sun? If so, then how did we ever get visible pictures of the OTHER SIDE of the moon? Did we use a gigantic flashbulb, or something? ;)
Map of the entire surface including the far side
The Far Side of the Moon Consider how this picture would look if it had been taken during a "full moon:" since during a full moon the entire side of the moon that is facing the Earth is lit up, only the portion of the moon in this photograph that is said to be visible from Earth (see the pic's caption) would have any sunlight on it.
Far Side of the Moon, with animation showing the same side of the moon always toward the Earth. This doesn't show where the sun is in relation to the animation; but figure that the sun is way off the screen from the animation...the darkened part of the moon in the animation is representing the side of the moon we never see from Earth, NOT how the light hits the moon (the Earth does not illuminate the moon, although it does sometimes reflect a little of the sun's light onto the dark portion of the quarter moon...)
So, taking this into account, will it be useful to build these lasers on the moon, especially the power plant?
Apollo 11 Laser Ranging Retroreflector Experiment. "Laser beams are used because they remain tightly focused for large distances. Nevertheless, there is enough dispersion of the beam that it is about 7 kilometers in diameter when it reaches the Moon and 20 kilometers in diameter when it returns to Earth. Because of this very weak signal, observations are made for several hours at a time. By averaging the signal for this period, the distance to the Moon can be measured to an accuracy of about 3 centimeters (the average distance from the Earth to the Moon is about 385,000 kilometers)."
Add to this, the fact that the moon wobbles...
Ah yes, here's a thought... ;) -
Re:Why bother?
>Not to mention the fact that one side of the
>moon faces the sun at all times! Any solar
>collectors on Earth are subject to day/night
>cycles. The moon would rarely be impacted, when
>the lunar eclipses happen.
Doh! One side of the moon always faces the EARTH! (synchronous rotation). We had never seen the far side of the moon until we sent something "back there" to take pictures.
So: that being the case, is it really possible that one side of the moon is always bathed in the light of the sun? If so, then how did we ever get visible pictures of the OTHER SIDE of the moon? Did we use a gigantic flashbulb, or something? ;)
Map of the entire surface including the far side
The Far Side of the Moon Consider how this picture would look if it had been taken during a "full moon:" since during a full moon the entire side of the moon that is facing the Earth is lit up, only the portion of the moon in this photograph that is said to be visible from Earth (see the pic's caption) would have any sunlight on it.
Far Side of the Moon, with animation showing the same side of the moon always toward the Earth. This doesn't show where the sun is in relation to the animation; but figure that the sun is way off the screen from the animation...the darkened part of the moon in the animation is representing the side of the moon we never see from Earth, NOT how the light hits the moon (the Earth does not illuminate the moon, although it does sometimes reflect a little of the sun's light onto the dark portion of the quarter moon...)
So, taking this into account, will it be useful to build these lasers on the moon, especially the power plant?
Apollo 11 Laser Ranging Retroreflector Experiment. "Laser beams are used because they remain tightly focused for large distances. Nevertheless, there is enough dispersion of the beam that it is about 7 kilometers in diameter when it reaches the Moon and 20 kilometers in diameter when it returns to Earth. Because of this very weak signal, observations are made for several hours at a time. By averaging the signal for this period, the distance to the Moon can be measured to an accuracy of about 3 centimeters (the average distance from the Earth to the Moon is about 385,000 kilometers)."
Add to this, the fact that the moon wobbles...
Ah yes, here's a thought... ;) -
Re:Why bother?
>Not to mention the fact that one side of the
>moon faces the sun at all times! Any solar
>collectors on Earth are subject to day/night
>cycles. The moon would rarely be impacted, when
>the lunar eclipses happen.
Doh! One side of the moon always faces the EARTH! (synchronous rotation). We had never seen the far side of the moon until we sent something "back there" to take pictures.
So: that being the case, is it really possible that one side of the moon is always bathed in the light of the sun? If so, then how did we ever get visible pictures of the OTHER SIDE of the moon? Did we use a gigantic flashbulb, or something? ;)
Map of the entire surface including the far side
The Far Side of the Moon Consider how this picture would look if it had been taken during a "full moon:" since during a full moon the entire side of the moon that is facing the Earth is lit up, only the portion of the moon in this photograph that is said to be visible from Earth (see the pic's caption) would have any sunlight on it.
Far Side of the Moon, with animation showing the same side of the moon always toward the Earth. This doesn't show where the sun is in relation to the animation; but figure that the sun is way off the screen from the animation...the darkened part of the moon in the animation is representing the side of the moon we never see from Earth, NOT how the light hits the moon (the Earth does not illuminate the moon, although it does sometimes reflect a little of the sun's light onto the dark portion of the quarter moon...)
So, taking this into account, will it be useful to build these lasers on the moon, especially the power plant?
Apollo 11 Laser Ranging Retroreflector Experiment. "Laser beams are used because they remain tightly focused for large distances. Nevertheless, there is enough dispersion of the beam that it is about 7 kilometers in diameter when it reaches the Moon and 20 kilometers in diameter when it returns to Earth. Because of this very weak signal, observations are made for several hours at a time. By averaging the signal for this period, the distance to the Moon can be measured to an accuracy of about 3 centimeters (the average distance from the Earth to the Moon is about 385,000 kilometers)."
Add to this, the fact that the moon wobbles...
Ah yes, here's a thought... ;) -
Apparently he's been at it for some time...
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Cymry (Jutland) and Bebryces (Gallaecia, Armorica)
Wow, Mr. AC, that is an informative and very on-topic link! Maybe there is hope for Shalshdot after all.
;-)"Maybe their fear was caused by Kaali meteorite impact at Saaremaa, Estonia which was a lot closer?"
I am not aware of Celtic tribes who feared that the sky might fall on their heads living in or near Estonia at the prehistoric times suggested by the article, but I will tell you what I know that might be relevant to your question in case you are interested:
- According to historians, the shores of the North sea and especially Jutland were once the home of the Cymvri or Cymry, who later migrated to Llydaw in north Britain and later -- circa 500AD -- proceeded southward to conquer Goidelic and Brythonnic Celts in present-day Wales. Interestingly, some believe that the Cymry had previously settled lands in or near Thracia and the Bosphorus, where other Celtic tribes also lived. Apparently, the Celtic populations in the Low Danube were, demographically speaking, very successful.
- The Kentaurs, who some say are the same as the Kantauri, and the Bebryces, who some say are the same as the Beribraces, also settled lands around the Black Sea, especially in Thracia, and yet later vanished from those lands, with some migrating toward the northwest of the Iberian peninsula (the Romans' Gallaecia) and present-day Brittany (the Romans' Armorica) -- leaving as early as 1400BC and arriving no later than around 700BC. Of these, the Bebryces at least were to be counted amongst the Celtic tribes to which the Romans referred, collectively, as the Gauls -- those primitive folk who feared that the sky might fall on their heads.
Thank you for the link, by the way. I wish you had posted while logged in. In any case, let me know what else you find.
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Re:instance in Celtic lore
Maybe their fear was caused by Kaali meteorite impact at Saaremaa, Estonia which was a lot closer?
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Re:all is not lost!
You are right.
M2P2 is probably the most significant space technology of this century. And how cool would it be if the first probe using this technology would be sent by a bunch of geeks sponsored by coca cola instead of slow, inefficient NASA...
Since a probe using M2P2 technology can be very lightweight, it might be possible to launch as a secondary payload on e.g. Ariane 5.
The most difficult task would be to get DSN coverage from NASA, since they would be reluctant to lend their facilities for a project not invented by them.
but it is definitely worth a try... -
all is not lost!
This particular budget cut is a travesty of magnificent proprtions. The celestial clock happens to be perfectly in tune with our technological advancement, to offer us this rare glimpse of our environment, as a species. To decide that we can't afford to redirect a few paltry resources to the task strikes me as narrow and crude. It's almost as if, as a species, we are too lazy to bother craning our necks a little to see what's outside the crib.
But it doesn't have to be this way. NASA isn't the only agency capable of sendiing the probe. in fact, maybe this feat could be accomplished on a voluntary basis? We have theories/plans for magical technology at our disposal, commercial support services to pester, potential launch capabilities and a wide variety of legal launch facilities around the world.
Consider: we have, just here at slashdot, the ears of a number of very technically capable individuals that might be persuaded to help create a Pluto Probe in an open sourced, ameteur manner. Corporate sponsorship would be soon to follow. Perhaps I haven't thought it out too carefully, but it is apparent to me that the potential to deploy a probe exists, despite the government.
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Re:Really?
::yawn:: first of all, Ive been posting a link to this site everytime anything space related shows up on Slashdot. Thanks for noticing. :/As to this being science fiction, well it can't rightly be fiction if it is under study RIGHT NOW, now can it? Besides, none of the projects listed are beyond our current understanding of physics and engineering. They arent on the lunatic fringe, they are only on the fringe of what what lies within the range of easy science and established expectations. The goals of the NASA Institute for Advanced Concepts (gasp! did you fail to realize the meaning of that? ADVANCED CONCEPTS, repeat 10 times times loud) are stated thus .
To quote:
While the NIAC seeks concepts which stretch the imagination, these concepts should be based on sound scientific principles. Now is your time to dream and stretch your imagination. The "Dreams" supported through the NIAC funding can be the framework for future NASA missions and programs. Advanced concept proposals should be aimed well beyond the evolution technical challenges that occupy current programs and set new, revolutionary directions in aeronautics and space. We are seeking advanced concepts, specifically systems and architectures, that are indeed "Grand" and revolutionary, and which will expand our vision of future possibilities.
Sheesh.
Derek -
The problem is different
I always thought the problems with figuring out how to do interstellar travel were mostly in theory - like how do we reach high velocities without using up impossible amounts of fuel or how do we steer these ships, but in fact, most of these papers have all that figured out but they're just waiting until we have the technology to manufacture stuff like the Solar Sail. That's actually pretty cool, we're closer than I thought
:) -
Intelligent Satellite Teams for Space Systems
Now this looks interesting. Nanotechnology for satellites. The only problem is space dust. It doesn't affect larger satellites, because they're, well, larger. Wouldn't nano-satellites encountering space dust be equivalent to regular satellites encountering asteroids? They'd be more susceptible to any forces acting upon them, because they have less mass (and are easier to move). If people can lose satellites WITHOUT having to worry about them being constantly knocked off course, wouldn't it be a good idea to stay away from this sort of thing? Just a thought.
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The real link
Here's the actual link to the NASA site. http://peaches.niac.usra.edu/studies/
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