To all those concerned about the power beam going off target and frying the neighbours - the easiest solution (even if it is just psychological) is to put the receiving station in the middle of a large lake or other body of water. That way if the beam does go off target all it does is slightly raise the temperature of some water (probably by an amount too small to measure). As I said - psychological. The same reason why the Sydney Harbour Bridge has four large pylons that are purely decorative.
As for using it as a weapon - sure, you could. And in doing so you'll be shutting off a large piece of the power supply to your own people. I think the greater concern is physical security of the actual transmitter. Bit hard to put barbed wire and guard dogs around a multi-square kilometre object 36000km above the surface of the Earth.
Hate to be the one that mentions it but the "Sydney Morning Herald" is an Australian newspaper owned by an Australian company. There isn't much a US law can do to them.
I was actually at the launch at the Hilton Hotel on Tuesday night.
The technology is amazing - the demo (ie, not production) version they had there was incredible, even without comparing it to any other screens or technology.
Whether they can get it out by Christmas 2007 at the price point they claim is something I will believe when I see. However, the tech is real and quite remarkable.
Australia maintains its current fleet of F-111s because they are the only things around with the legs to fly from Aus, bomb Jakarta and return without refueling.
We buy American hardware because they are our number one military ally and it is all about standardised hardware in the field. If our allies are flying/driving/firing apples we don't want to be flying/driving/firing oranges.
Did anyone else notice the glaring spelling and grammatical errors on the company's website?
* New South Whales (should be Wales - as in the country) * Incorrect use of capitalisation - earth (should be capitalised), Movie (should not be) * The place in NSW where the radio telescope is is called Parkes (not Parks) and the movie it appears in is called "The Dish" (not "Dish").
Do we really want these people communicating on our behalf?
I'd have to recommend LRSE Hosting. They are fantastic.
Besides offering Slash and Scoop they have static accounts from $15/month. Even though I am on the other side of the globe (Australia) I always get responses to emails within a few hours.
The US Government cannot pay money to Russia for launch services due to an Act of Congress. This was passed to prevent any monies going to Russia (or the Soviet Union) after they supplied weapons to Iran.
This announcement by the RSA is nothing more than a rehash of an old argument - and one that will not be solved any time soon as it would require an Act of Congress.
The only way it can be resolved realistically is through a barter arrangement (which is what RSA is suggesting in some reports). Hence, not a lot of immediate use to the "cash-strapped Russian space program".
In Australia at least, anyone wanting to be considered eligble under the law as a telco provider needs to be able to guarantee connection for phone calls to emergency services.
I know this is has presented itself for wireless networks seeking official blessing and the freedom to carry certain kinds of traffic legally.
Generally, ad-hoc networks can't (at least not without major investment) deliver this fundamental.
I for one think this requirement is a good reason to keep telcos - Sorry, no route to host errors when you need an ambulance would not be fun.
You've got a great idea there in terms of funding new ideas - of course it sounds very similar to an IPO. For your $25/month would you require any return? And how soon would you want that return?
$25/month works out to $300/year. To raise $200m you need close to 700,000 "investors" who will be willing to not get a return for up to 6 or 7 years. Maybe it will work - maybe because each person invests so little they are willing to wait a longer time. However - 700,000 is greater the combined membership of all the world's space groups.
As for the cable - the only way it will be cheaper to build it in space is if you have built up significant orbital infrastructure, including a serious mining industry. At that point, a space elevator is a good thing. Not only does it allow cheap access to space it also allows cheap access from space. Which means you can easily and safely transport mined and/or processed goods back to Earth.
If you want to discuss this further email me - space at astraaustralis dot com dot au.
HighLift's (now Liftport) report for NASA on the design and construction of a space elevator from a carbon nanotube-polymer matrix costs the entire enterprise at between $20-$40 billion. This is a multi-year program (15 years) using only terrestrial resources. Your assumption that as soon as scientists devise a means of building long carbon nanotubes someone will build a space elevator is flawed. As is your assumption that the cable will be built from space resources. You can find a copy of the report at both the HighLift and LiftPort websites.
A mission to an asteroid is likely to cost more than $6m - probably closer to $200m. Of course, that is equivalent to launching 20,000 kg of water to LEO. Couple that with some Pt group metals ($14,000/kg - on earth) and you have paid off your mission. If you've been clever, you spacecraft can do another mining mission with a minimal refit (maybe without one). So you tools are paid off - almost everything from here on in is profit.
As for why no-one has written a cheque for the operation yet - again we come back to the need for a salesman. This is coupled with the fact that until now there has been no real opportunity for commercial development of space.
Lift cost may indeed go down by a factor of 100 "when they figure out how to make very long carbon nanotubes". But it will still cost $40 billion to build the elevator out of those nanotubes.
As for equipment needed to mine an asteroid. To get water out of a carbonaceous asteroid all you have to do is heat it. Bring the water back to HEEO and it is worth $10,000/kg - what it costs to launch it from Earth. For only a few hundred kg of launch mass you can bring back tens of thousands of kg of water - and fuel for your next mission out. Read "Mining the Sky" by John Lewis, Prof of Planetary Sciences at Uni Of Arizona-Tucson.
With the resupply burden lifted, the development of in-orbit infrastructure is greatly advanced.
As for my Catch-22 - it is correct, with the current situation. I can think of hundreds of ways it can be broken by changing the situation. Building a space elevator is one of these.
There will be a demand when launch costs come down. Launch costs will come down when there is demand. We need to find a way to break this cycle. And the best way is to stop launching everything.
The space elevator is GREAT. However, you seem to think that it is more likely to find $40 billion to build the elevator than possibly less than $1 billion to start asteroid mining.
Even with the elevator, it makes NO SENSE to carry all the material you need to orbit from Earth.
We have the ability to do all those things now. Mining asteroids is a technical challenge that can be solved.
What is lacking is not the ability but the resolve. And the most important thing - the salesman. What we need is someone who understands the whole concept who is able to sell it to investors.
Only if you insist on building everything on the Earth and then launching it
Re:Wouldn't atmospheric dissipation of a microwave
on
Nucular Hydrogen Economy
·
· Score: 2, Informative
Actually no. Whilst the power density of the beam would be higher, the actual power transmitted would be quite low.
We actually did some modelling of beaming power from Earth to geostationary orbit. Without looking at any of the numbers (ie, what I remember) - to get an equivalent power level to the Sun (1300W/m^2) we only needed 470-odd W/m^2 at a particular wavelength (it was a matter of tuning the laser to the existing solar cells) with a spot diameter of 140m. This meant that we needed something like a 1-2MW laser on the ground (36000km is a long way for) with a 1m beam diameter. So, whilst the power density at the transmitter end is high, by the time it gets anywhere useful, the power density is very low. Of course, if you wanted to transmit more power then all the numbers go up.
Actually, microwave transmission is not the way to go if you want a nice, compact system. Whilst the tranmitter gear is easier with microwaves, the receiver must be huge for any realistic system.
A better bet is lasers with tuned photovoltaic cells at the receiver. You can get upwards of 80% efficiency and the spot beam diameter at 36000km (geostationary orbit - sunlight about 99.5% of the time) is only about 140m.
The best bit about doing it in space is actually the fact that you can use low efficiency cells (which are cheap to manufacture). Because you have no real space restrictions you can make your array as large as you want. It turns out it is cheaper to make a large array of low efficiency cells than a small array of high efficiency cells.
As for why NASA hasn't done it yet - you'd have to ask them and your politicians. I am an Australian - so NASA isn't responsible to me. One would guess that it is because of the original studies combined with a need to complete the ISS before moving onto anything else. The other reason is because there isd no reason for NASA to do it. Something like this should be built by private industry - not the government.
There is one clean and safe way of generating as much power as we will need for the forseeable future. Orbiting solar power stations.
Whilst the original designs for these were costed in the billions - intelligent design and utilisation of space bourne resources would reduce the costs by orders of magnitude.
No more pollution. No more need to build new power stations (coal, gas, nuclear, wind, solar, wave, etc). Just a few fields of photovoltaic arrays a few square kilometres across and the use of existing distribution networks.
Get off your high horse. The general fact about volunteer organisations is they are under-resourced and over-worked at the best of times. The poster is looking for an existing solution. They (probably) do not have the time or the resources to go about developing their own solution.
If you want to claim that it's not that hard then go and work for a volunteer org for a few months.
As someone who has spent time with EDUCATED American high school students I can tell you that the problem the US has is ignorance and a poor education system.
When an "intelligent" high school student needs to ask where South Africa is or what season is it in Australia you know that there is something wrong.
Just like here I was told that Henry Ford invented the automobile. And the speaker refused to accept that he was wrong - even when presented with the facts by Brits, Australians and Germans.
Slashdot Mirror
To all those concerned about the power beam going off target and frying the neighbours - the easiest solution (even if it is just psychological) is to put the receiving station in the middle of a large lake or other body of water. That way if the beam does go off target all it does is slightly raise the temperature of some water (probably by an amount too small to measure). As I said - psychological. The same reason why the Sydney Harbour Bridge has four large pylons that are purely decorative.
As for using it as a weapon - sure, you could. And in doing so you'll be shutting off a large piece of the power supply to your own people. I think the greater concern is physical security of the actual transmitter. Bit hard to put barbed wire and guard dogs around a multi-square kilometre object 36000km above the surface of the Earth.
Hate to be the one that mentions it but the "Sydney Morning Herald" is an Australian newspaper owned by an Australian company. There isn't much a US law can do to them.
I was actually at the launch at the Hilton Hotel on Tuesday night.
The technology is amazing - the demo (ie, not production) version they had there was incredible, even without comparing it to any other screens or technology.
Whether they can get it out by Christmas 2007 at the price point they claim is something I will believe when I see. However, the tech is real and quite remarkable.
Australia maintains its current fleet of F-111s because they are the only things around with the legs to fly from Aus, bomb Jakarta and return without refueling.
We buy American hardware because they are our number one military ally and it is all about standardised hardware in the field. If our allies are flying/driving/firing apples we don't want to be flying/driving/firing oranges.
Did anyone else notice the glaring spelling and grammatical errors on the company's website?
* New South Whales (should be Wales - as in the country)
* Incorrect use of capitalisation - earth (should be capitalised), Movie (should not be)
* The place in NSW where the radio telescope is is called Parkes (not Parks) and the movie it appears in is called "The Dish" (not "Dish").
Do we really want these people communicating on our behalf?
Besides offering Slash and Scoop they have static accounts from $15/month. Even though I am on the other side of the globe (Australia) I always get responses to emails within a few hours.
These guys are great.
The US Government cannot pay money to Russia for launch services due to an Act of Congress. This was passed to prevent any monies going to Russia (or the Soviet Union) after they supplied weapons to Iran.
This announcement by the RSA is nothing more than a rehash of an old argument - and one that will not be solved any time soon as it would require an Act of Congress.
The only way it can be resolved realistically is through a barter arrangement (which is what RSA is suggesting in some reports). Hence, not a lot of immediate use to the "cash-strapped Russian space program".
Australia is as large as the continental US with a popolation 15 times smaller. Yet all the mobile phone networks cover the entire country.
This is due to legislation that stated if you want to build a mobile network in Australia you must cover the entire country.
Try Phprojekt. We are deploying this to manage a geographically dispersed volunteer organisation.
Optus Cable has monthly caps but they don't charge you extra if you go over. They just slow you down to 28k (yes, a very old dial up).
In Australia at least, anyone wanting to be considered eligble under the law as a telco provider needs to be able to guarantee connection for phone calls to emergency services.
I know this is has presented itself for wireless networks seeking official blessing and the freedom to carry certain kinds of traffic legally.
Generally, ad-hoc networks can't (at least not without major investment) deliver this fundamental.
I for one think this requirement is a good reason to keep telcos - Sorry, no route to host errors when you need an ambulance would not be fun.
You've got a great idea there in terms of funding new ideas - of course it sounds very similar to an IPO. For your $25/month would you require any return? And how soon would you want that return?
$25/month works out to $300/year. To raise $200m you need close to 700,000 "investors" who will be willing to not get a return for up to 6 or 7 years. Maybe it will work - maybe because each person invests so little they are willing to wait a longer time. However - 700,000 is greater the combined membership of all the world's space groups.
As for the cable - the only way it will be cheaper to build it in space is if you have built up significant orbital infrastructure, including a serious mining industry. At that point, a space elevator is a good thing. Not only does it allow cheap access to space it also allows cheap access from space. Which means you can easily and safely transport mined and/or processed goods back to Earth.
If you want to discuss this further email me - space at astraaustralis dot com dot au.
HighLift's (now Liftport) report for NASA on the design and construction of a space elevator from a carbon nanotube-polymer matrix costs the entire enterprise at between $20-$40 billion. This is a multi-year program (15 years) using only terrestrial resources. Your assumption that as soon as scientists devise a means of building long carbon nanotubes someone will build a space elevator is flawed. As is your assumption that the cable will be built from space resources. You can find a copy of the report at both the HighLift and LiftPort websites.
A mission to an asteroid is likely to cost more than $6m - probably closer to $200m. Of course, that is equivalent to launching 20,000 kg of water to LEO. Couple that with some Pt group metals ($14,000/kg - on earth) and you have paid off your mission. If you've been clever, you spacecraft can do another mining mission with a minimal refit (maybe without one). So you tools are paid off - almost everything from here on in is profit.
As for why no-one has written a cheque for the operation yet - again we come back to the need for a salesman. This is coupled with the fact that until now there has been no real opportunity for commercial development of space.
Lift cost may indeed go down by a factor of 100 "when they figure out how to make very long carbon nanotubes". But it will still cost $40 billion to build the elevator out of those nanotubes.
As for equipment needed to mine an asteroid. To get water out of a carbonaceous asteroid all you have to do is heat it. Bring the water back to HEEO and it is worth $10,000/kg - what it costs to launch it from Earth. For only a few hundred kg of launch mass you can bring back tens of thousands of kg of water - and fuel for your next mission out. Read "Mining the Sky" by John Lewis, Prof of Planetary Sciences at Uni Of Arizona-Tucson.
With the resupply burden lifted, the development of in-orbit infrastructure is greatly advanced.
As for my Catch-22 - it is correct, with the current situation. I can think of hundreds of ways it can be broken by changing the situation. Building a space elevator is one of these.
There will be a demand when launch costs come down. Launch costs will come down when there is demand. We need to find a way to break this cycle. And the best way is to stop launching everything.
The space elevator is GREAT. However, you seem to think that it is more likely to find $40 billion to build the elevator than possibly less than $1 billion to start asteroid mining.
Even with the elevator, it makes NO SENSE to carry all the material you need to orbit from Earth.
We have the ability to do all those things now. Mining asteroids is a technical challenge that can be solved.
What is lacking is not the ability but the resolve. And the most important thing - the salesman. What we need is someone who understands the whole concept who is able to sell it to investors.
Only if you insist on building everything on the Earth and then launching it
Actually no. Whilst the power density of the beam would be higher, the actual power transmitted would be quite low.
We actually did some modelling of beaming power from Earth to geostationary orbit. Without looking at any of the numbers (ie, what I remember) - to get an equivalent power level to the Sun (1300W/m^2) we only needed 470-odd W/m^2 at a particular wavelength (it was a matter of tuning the laser to the existing solar cells) with a spot diameter of 140m. This meant that we needed something like a 1-2MW laser on the ground (36000km is a long way for) with a 1m beam diameter. So, whilst the power density at the transmitter end is high, by the time it gets anywhere useful, the power density is very low. Of course, if you wanted to transmit more power then all the numbers go up.
Actually, microwave transmission is not the way to go if you want a nice, compact system. Whilst the tranmitter gear is easier with microwaves, the receiver must be huge for any realistic system.
A better bet is lasers with tuned photovoltaic cells at the receiver. You can get upwards of 80% efficiency and the spot beam diameter at 36000km (geostationary orbit - sunlight about 99.5% of the time) is only about 140m.
The best bit about doing it in space is actually the fact that you can use low efficiency cells (which are cheap to manufacture). Because you have no real space restrictions you can make your array as large as you want. It turns out it is cheaper to make a large array of low efficiency cells than a small array of high efficiency cells.
As for why NASA hasn't done it yet - you'd have to ask them and your politicians. I am an Australian - so NASA isn't responsible to me. One would guess that it is because of the original studies combined with a need to complete the ISS before moving onto anything else. The other reason is because there isd no reason for NASA to do it. Something like this should be built by private industry - not the government.
There is one clean and safe way of generating as much power as we will need for the forseeable future. Orbiting solar power stations.
Whilst the original designs for these were costed in the billions - intelligent design and utilisation of space bourne resources would reduce the costs by orders of magnitude.
No more pollution. No more need to build new power stations (coal, gas, nuclear, wind, solar, wave, etc). Just a few fields of photovoltaic arrays a few square kilometres across and the use of existing distribution networks.
Actually, under international and national copyright laws, pornographic images are not protected by copyright.
Which is why there are so many porn sites. A few develop the content and the rest just rip them off with no legal repercussion,
And we are involved in the war.
For a fairly neutral, balanced view, try the Sydney Morning Herald.
Get off your high horse. The general fact about volunteer organisations is they are under-resourced and over-worked at the best of times. The poster is looking for an existing solution. They (probably) do not have the time or the resources to go about developing their own solution.
If you want to claim that it's not that hard then go and work for a volunteer org for a few months.
When an "intelligent" high school student needs to ask where South Africa is or what season is it in Australia you know that there is something wrong.
Just like here I was told that Henry Ford invented the automobile. And the speaker refused to accept that he was wrong - even when presented with the facts by Brits, Australians and Germans.