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 Posted: Fri Jun 20, 2008 1:11 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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On Jun 20, 6:17 am, Ian Parker <ianpark...@gmail.com> wrote:
| Quote: |
The cost of getting material to LEO is a major factor. This may well
be "chicken and egg". I propose mixing finely divided soot (order of ë/
4) with liquid hydrogen and having an intensity (optical/NIR) of
gigawatts m^2. The Nerva engine (nuclear) was designed to deliver 9 km/
s in its exhaust. I think we could get to 10km/s fairly easily. This
would be the logical route to LEO.
- Ian Parker
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wrong, NERVA was never meant for access to LEO |
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Pat Flannery
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| Posted: Fri Jun 20, 2008 6:50 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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charliexmurphy@yahoo.com wrote:
| Quote: |
The cost of getting material to LEO is a major factor. This may well
be "chicken and egg". I propose mixing finely divided soot (order of ë/
4) with liquid hydrogen and having an intensity (optical/NIR) of
gigawatts m^2. The Nerva engine (nuclear) was designed to deliver 9 km/
s in its exhaust. I think we could get to 10km/s fairly easily. This
would be the logical route to LEO.
- Ian Parker
wrong, NERVA was never meant for access to LEO
|
The follow-on Timberwind nuclear rocket engine system was though.
Pat |
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Ian Parker
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| Posted: Fri Jun 20, 2008 9:41 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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On 20 Jun, 14:11, charliexmur...@yahoo.com wrote:
| Quote: |
On Jun 20, 6:17 am, Ian Parker <ianpark...@gmail.com> wrote:
The cost of getting material to LEO is a major factor. This may well
be "chicken and egg". I propose mixing finely divided soot (order of ë/
4) with liquid hydrogen and having an intensity (optical/NIR) of
gigawatts m^2. The Nerva engine (nuclear) was designed to deliver 9 km/
s in its exhaust. I think we could get to 10km/s fairly easily. This
would be the logical route to LEO.
- Ian Parker
wrong, NERVA was never meant for access to LEO
|
This is really irrelevant. The point is that we need approx 8km/sec to
reach LEO. If our exhaust velocity is 10 we wiill have a payload +
deadweight of exp(-0. of total weight. In other words about 55% of
the take off weight will be fuel.
I was never claiming that NERVA was designed for LEO. I was simply
comparing exhaust velocities. LH with soot in it should be rather
better than a nuclear reactor. The lasers are directly heating the
soot. There is no radioactive material so LEO is perfectly possile.
Beyond LEO we have ion propulsion. A nuclear reactor starting off NOT
in orbit would be incredibly dangerous. Lasers and soot imply no
radioactive material and are suitable for LEO. In fact I would
advocate something likre an aircraft wiith air breathing LH motors
carrying you up to 15km and (possibly) Mach 3. The turbo/scram jets
will separate and fly back to Earth. You need to go to 10km to clear
the Earth.
With an aircraft about 50% will be fuel as we will be travellling at
some 800m/s before rocket power kicks in.
- Ian Parker |
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Pat Flannery
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| Posted: Sat Jun 21, 2008 6:17 am Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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Ian Parker wrote:
| Quote: |
In fact I would
advocate something likre an aircraft wiith air breathing LH motors
carrying you up to 15km and (possibly) Mach 3. The turbo/scram jets
will separate and fly back to Earth. You need to go to 10km to clear
the Earth.
|
For only Mach 3 you don't need scramjets...for that matter you don't
even need ramjets; LH2-powered expander cycle turbojets will get you up
to that speed: http://en.wikipedia.org/wiki/Lockheed_CL-400_Suntan
Although it might be a lot simpler to go with more conventional
turbo-ramjets like the SR-71 used to hit Mach 3.2.
Now, if you meant Mach _13_...then you are well into scramjet or ducted
rocket territory, and the ducted rocket might be the simpler way to go;
as it gives you the ability to take off from a runway on pure rocket
power, or at least using off-the-shelf turbojet or turbofan engines, to
get you up to around Mach 2.5 before you fire up the ducted rocket.
Pat |
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jonathan
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| Posted: Sat Jun 21, 2008 11:00 am Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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"Rand Simberg" <simberg.interglobal@org.trash> wrote in message
news:486e2560.280846125@news.giganews.com...
It is a small amount. Imagine what advances might occur
with SSP if some money /were spent/ researching
the needed breakthroughs?
| Quote: |
As a former project manager of SPS at a major aerospace corporation, I
know John Mankins quite well.
None of this supports your insane and ignorant contention that Bush
killed SPS and replaced it with VSE.
|
Are you saying Bush didn't kill SERT? Then who did?
Are you saying Bush didn't create the Vision? Then who did?
Are you feeling ok?
Why is the couple of years important? When we needed a new
energy policy, what did Cheney do???
You know what he did, everyone knows, he invited all the big oil execs
and asked them "what policies do you want". And now the oil companies
have profits that exceed anything in human history.
After Columbia, when we needed a new space policy, do you really
think it was any different???
....................................................................
ARE YOU THAT NAIVE?
...................................................................
Why was the X-33 canceled? Was it the fuel tanks? Pahlease.
Do you think Lockheed wanted to build something that would
take them out of the launch business, and give it to
someone else???
Just like Big Oil, Big Aero and the military got just what they
wanted with Bush. Instead of small cheap launchers, we get
just the opposite....Shiny New Saturn 5's. Instead of
SSP, we get a new moon base for missile defense.
Like that commercial, I can see the Corporate Monkeys
turning the chart 90 degrees to show it going up instead
of down, giggling and puffing on cigars made of money.
I don't know what makes me sadder, that NASA, the
American people and our future have been sold out
by a crony-driven administration, or that no one seems
to give a damn.
Don't bother replying, I wouldn't want OM to blow a gasket.
One more response to me and I fear a big fat vein in his forehead
might start to throb..and..throb and go....POP!
After all, this is OM's ng, and he should have the final
say over who says what to who and how.
No wonder Bush rolled over you NASA types
without giving it a second thought.
You're so naive.
Ya know, when Richard Nixon picked John Dean to
be his personal attorney, do you know what Dean's
resume looked like? Dean had just been fired from
his first job out of college after only a few months.
Dean then went to DC for the /only reason/ because
he couldn't pass the bar exam in any other state.
DC was known to be the easiest, and it took him
four tries to pass. He applied all over town and not
a single call came from anyone, and he concluded his law
career was probably over. Needless to say, he didn't
think to apply at the White House. Duh!
But lo and behold, he got a call from the White House
offering him the job without so much as an interview.
In fact, the caller said show up at the White House
/tomorrow/ and you're hired. He showed up an
hour early!
Why?
Nixon got a flunky that so desperately wanted the job, that
he'd do anything at all (legal or not) to keep it.
Now you know how the current NASA head got his job, same
corrupt tactics. He wasn't even on the original short list of
candidates. I bet he didn't even apply for the job.
When those two /jr White House staffers/ were tasked to outline
a new space policy, who do you think was 'advising' them???
Jonathan
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Ian Parker
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| Posted: Sat Jun 21, 2008 11:25 am Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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On 21 Jun, 02:17, Pat Flannery <flan...@daktel.com> wrote:
| Quote: |
Ian Parker wrote:
In fact I would
advocate something likre an aircraft wiith air breathing LH motors
carrying you up to 15km and (possibly) Mach 3. The turbo/scram jets
will separate and fly back to Earth. You need to go to 10km to clear
the Earth.
For only Mach 3 you don't need scramjets...for that matter you don't
even need ramjets; LH2-powered expander cycle turbojets will get you up
to that speed:http://en.wikipedia.org/wiki/Lockheed_CL-400_Suntan
Although it might be a lot simpler to go with more conventional
turbo-ramjets like the SR-71 used to hit Mach 3.2.
Now, if you meant Mach _13_...then you are well into scramjet or ducted
rocket territory, and the ducted rocket might be the simpler way to go;
as it gives you the ability to take off from a runway on pure rocket
power, or at least using off-the-shelf turbojet or turbofan engines, to
get you up to around Mach 2.5 before you fire up the ducted rocket.
There are in fact quite a large number of permutations and |
combinations. You might want to use a scramjet at a lower speed than
you might otherwise as if your "combustion zone" was visible from
space you might not need fuel, only lambda/4 soot.
The figures for total fuel load show a remarkable similarity to
Concorde. I think the deadweight could be sent well below Concorde.
Fares BTW were something like $5,000 for a 2 way flight across the
Atlantic. British Airways towards the end promoted Concorde as a
luxury product and the fares approached $10,000. Here the analogy
ends, this is a cargo plane predominantly.
- Ian Parker |
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Ian Parker
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| Posted: Sat Jun 21, 2008 2:11 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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On 21 Jun, 14:42, simberg.interglo...@org.trash (Rand Simberg) wrote:
| Quote: |
On Sat, 21 Jun 2008 22:23:13 -0400, in a place far, far away,
"jonathan" <H...@write.instead.net> made the phosphor on my monitor
glow in such a way as to indicate that:
None of this supports your insane and ignorant contention that Bush
killed SPS and replaced it with VSE.
Are you saying Bush didn't kill SERT?
No. SERT wasn't SPS. There was no program.
Are you saying Bush didn't create the Vision?
No. But it wasn't a replacement for SPS.
Are you feeling ok?
Fine, thanks.
rest of paranoid delusions from "jonathan" snipped
|
This is what I have always been saying in the thread on "rubbish
postings". you do not talk about "phosphors on monitors" at scientific
conferences, and theis seems to be built into every reply - to anyone.
- Ian Parker |
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Rand Simberg
Guest
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| Posted: Sat Jun 21, 2008 6:42 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
|
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On Sat, 21 Jun 2008 22:23:13 -0400, in a place far, far away,
"jonathan" <Home@write.instead.net> made the phosphor on my monitor
glow in such a way as to indicate that:
| Quote: |
None of this supports your insane and ignorant contention that Bush
killed SPS and replaced it with VSE.
Are you saying Bush didn't kill SERT?
|
No. SERT wasn't SPS. There was no program.
| Quote: |
Are you saying Bush didn't create the Vision?
|
No. But it wasn't a replacement for SPS.
| Quote: |
Are you feeling ok?
|
Fine, thanks.
<rest of paranoid delusions from "jonathan" snipped> |
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jonathan
Guest
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| Posted: Sat Jun 21, 2008 8:06 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
|
|
"Rand Simberg" <simberg.interglobal@org.trash> wrote in message
news:487204ec.403609890@news.giganews.com...
| Quote: |
On Sat, 21 Jun 2008 22:23:13 -0400, in a place far, far away,
"jonathan" <Home@write.instead.net> made the phosphor on my monitor
glow in such a way as to indicate that:
|
| Quote: |
Are you saying Bush didn't kill SERT?
|
| Quote: |
No. SERT wasn't SPS. There was no program.
|
Which of the following words do you not understand?
"NASA'S SPACE SOLAR POWER EXPLORATORY
RESEARCH AND TECHNOLOGY PROGRAM (SERT)
The National Aeronautics and Space Administration's Space
Solar Power (SSP) Exploratory Research and Technology
(SERT) program was charged to develop technologies
needed to provide cost-competitive ground baseload electrical
power from space-based solar energy converters."
http://www.nap.edu/openbook.php?record_id=10202&page=1
Of course, they use the acronym SSP, when I use SPS.
....tomato-tamahto. Is that the crux of your 'argument'?
Please tell me that's not it?
| Quote: |
Are you saying Bush didn't create the Vision?
No. But it wasn't a replacement for SPS.
|
Ok ....o n e c a m e a f t e r t h e o t h e r.
| Quote: |
Are you feeling ok?
Fine, thanks.
|
I'm reserving judgment on your sanity for now~
| Quote: |
rest of paranoid delusions from "jonathan" snipped
|
....rest is .../documented/ below.
That's why Cheney appealed all the way to the Supreme
Court (and lost) to keep secret the people that he
met with in creating our energy policy? That's why
the oil execs lied to Congress they were at those
meetings? Because they have nothing to hide?
The environmentalists were brought in after
the energy policy had already been written
and decided. It was much the same for the
Vision and NASA. It's how they do business.
Read for yourself
Papers Detail Industry's Role in Cheney's Energy Report
By Michael Abramowitz and Steven Mufson
Washington Post Staff Writers
Wednesday, July 18, 2007; Page A01
http://www.washingtonpost.com/wp-dyn/content/article/2007/07/17/AR2007071701987.html?nav=rss_politics |
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kT
Guest
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| Posted: Sat Jun 21, 2008 9:55 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
|
|
jonathan wrote:
| Quote: |
"Rand Simberg" <simberg.interglobal@org.trash> wrote in message
news:486e2560.280846125@news.giganews.com...
On Fri, 20 Jun 2008 23:00:28 -0400, in a place far, far away,
"jonathan" <Home@write.instead.net> made the phosphor on my monitor
glow in such a way as to indicate that:
SERT spent $22 million in 99 and 2000.
http://www.rish.kyoto-u.ac.jp/jusps/KA-2.pdf
http://www.hq.nasa.gov/office/legaff/mankins9-7.html
A completely trivial amount of money for a "program." And again, it
has nothing do to with what happened in 2004.
It is a small amount. Imagine what advances might occur
with SSP if some money /were spent/ researching
the needed breakthroughs?
As a former project manager of SPS at a major aerospace corporation, I
know John Mankins quite well.
None of this supports your insane and ignorant contention that Bush
killed SPS and replaced it with VSE.
Are you saying Bush didn't kill SERT? Then who did?
Are you saying Bush didn't create the Vision? Then who did?
Are you feeling ok?
Why is the couple of years important? When we needed a new
energy policy, what did Cheney do???
You know what he did, everyone knows, he invited all the big oil execs
and asked them "what policies do you want". And now the oil companies
have profits that exceed anything in human history.
After Columbia, when we needed a new space policy, do you really
think it was any different???
...................................................................
ARE YOU THAT NAIVE?
..................................................................
Why was the X-33 canceled? Was it the fuel tanks? Pahlease.
Do you think Lockheed wanted to build something that would
take them out of the launch business, and give it to
someone else???
Just like Big Oil, Big Aero and the military got just what they
wanted with Bush. Instead of small cheap launchers, we get
just the opposite....Shiny New Saturn 5's. Instead of
SSP, we get a new moon base for missile defense.
Like that commercial, I can see the Corporate Monkeys
turning the chart 90 degrees to show it going up instead
of down, giggling and puffing on cigars made of money.
I don't know what makes me sadder, that NASA, the
American people and our future have been sold out
by a crony-driven administration, or that no one seems
to give a damn.
Don't bother replying, I wouldn't want OM to blow a gasket.
One more response to me and I fear a big fat vein in his forehead
might start to throb..and..throb and go....POP!
After all, this is OM's ng, and he should have the final
say over who says what to who and how.
No wonder Bush rolled over you NASA types
without giving it a second thought.
You're so naive.
Ya know, when Richard Nixon picked John Dean to
be his personal attorney, do you know what Dean's
resume looked like? Dean had just been fired from
his first job out of college after only a few months.
Dean then went to DC for the /only reason/ because
he couldn't pass the bar exam in any other state.
DC was known to be the easiest, and it took him
four tries to pass. He applied all over town and not
a single call came from anyone, and he concluded his law
career was probably over. Needless to say, he didn't
think to apply at the White House. Duh!
But lo and behold, he got a call from the White House
offering him the job without so much as an interview.
In fact, the caller said show up at the White House
/tomorrow/ and you're hired. He showed up an
hour early!
Why?
Nixon got a flunky that so desperately wanted the job, that
he'd do anything at all (legal or not) to keep it.
Now you know how the current NASA head got his job, same
corrupt tactics. He wasn't even on the original short list of
candidates. I bet he didn't even apply for the job.
When those two /jr White House staffers/ were tasked to outline
a new space policy, who do you think was 'advising' them???
Jonathan
|
Jonathon's on a roll.
Keep your eye on the horizon down there this summer, eh? |
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Ian Stirling
Guest
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| Posted: Sun Jun 22, 2008 2:12 am Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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In sci.space.policy Ian Parker <ianparker2@gmail.com> wrote:
| Quote: |
There is one or twi things in the report to pick up on.
snip
If you go for my suggestion of phased arrays you do not need a power
management system. You simply have each transmitter giving a kilowatt
or less. Voltages need be no higher than TTL (Transistor to Transistor
Logic). You do though need a computing system though.
Beauty of this too is that the beam can be turned instantaneously from
point to point. You can focus it on the ISS when it is in darkness, or
somewhere else when it is not. If you want non nuclear propulsion you
have to follow a spacecraft. You may even want to power 2 at the same
time.
|
Unfortunately.
Broadly, you can't assume that 1000 1w transmitters spread over a 1Km
circle are the same as a nice full dish.
If you have a total area as large as 10% of the 1Km dish, spread over a
1Km circle, then you have a point-spread-function that approaches, perhaps
closely the 1Km dish.
However, all this means is that the central lobe is as tight as the 1Km
dish, it says nothing about its intensity.
The rest of the input power (90% in this case) sprays 'everywhere'
(within the beamwidth of the individual antennas.)
As a simple reason why this is so - consider focussing a beam from a large
antenna made up from 1000 little antennas onto a near diffraction limited
spot.
Now, all radio antennas work equally as well backwards and forwards.
So, place a transmitter at the spot, that |
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Pat Flannery
Guest
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| Posted: Sun Jun 22, 2008 4:47 am Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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Ian Parker wrote:
| Quote: |
The figures for total fuel load show a remarkable similarity to
Concorde. I think the deadweight could be sent well below Concorde.
Fares BTW were something like $5,000 for a 2 way flight across the
Atlantic. British Airways towards the end promoted Concorde as a
luxury product and the fares approached $10,000. Here the analogy
ends, this is a cargo plane predominantly.
|
That sounds like this thing: http://www.reactionengines.co.uk/lapcat.html
Pat |
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Ian Parker
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| Posted: Sun Jun 22, 2008 7:22 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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On 21 Jun, 22:12, r...@mauve.plus.com (Ian Stirling) wrote:
| Quote: |
In sci.space.policy Ian Parker <ianpark...@gmail.com> wrote:
There is one or twi things in the report to pick up on.
snip
If you go for my suggestion of phased arrays you do not need a power
management system. You simply have each transmitter giving a kilowatt
or less. Voltages need be no higher than TTL (Transistor to Transistor
Logic). You do though need a computing system though.
Beauty of this too is that the beam can be turned instantaneously from
point to point. You can focus it on the ISS when it is in darkness, or
somewhere else when it is not. If you want non nuclear propulsion you
have to follow a spacecraft. You may even want to power 2 at the same
time.
Unfortunately.
Broadly, you can't assume that 1000 1w transmitters spread over a 1Km
circle are the same as a nice full dish.
If you have a total area as large as 10% of the 1Km dish, spread over a
1Km circle, then you have a point-spread-function that approaches, perhaps
closely the 1Km dish.
However, all this means is that the central lobe is as tight as the 1Km
dish, it says nothing about its intensity.
The rest of the input power (90% in this case) sprays 'everywhere'
(within the beamwidth of the individual antennas.)
As a simple reason why this is so - consider focussing a beam from a large
antenna made up from 1000 little antennas onto a near diffraction limited
spot.
Now, all radio antennas work equally as well backwards and forwards.
So, place a transmitter at the spot, that
|
You are quite right in assuming that a sparse 1km disc is not the same
as a filled in dish. There is in fact something of a principle of
duality here. Total laser area will translate into diffraction limited
optics. There are some permutations on this. Suppose we are in a
desert and we decide to lay out (terrestrial) solar installations in a
grid pattern. We also want them to provide power at night as well. If
we lay out a diffraction grating in space we can do this with a sparse
array. We have a diffraction grating at source which provides a grid
pattern at the destination.
Suppose we have a pattern that departs from a grid. Here life gets a
little bit complicated. Our pattern gives a pattern in space. There
will be homotopic relations governing what we can have on the ground.
This is quite interesting pure maths.
However the thrust of my argument in my earlier posings was not
precise details of homotopic relations in sparse grids but the fact
that we can have low voltages and no superconducting cable. Provided
our total area is the same we can have the same diffraction pattern.
- Ian Parker |
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Ian Parker
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| Posted: Sun Jun 22, 2008 7:25 pm Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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On 22 Jun, 00:47, Pat Flannery <flan...@daktel.com> wrote:
| Quote: |
Ian Parker wrote:
The figures for total fuel load show a remarkable similarity to
Concorde. I think the deadweight could be sent well below Concorde.
Fares BTW were something like $5,000 for a 2 way flight across the
Atlantic. British Airways towards the end promoted Concorde as a
luxury product and the fares approached $10,000. Here the analogy
ends, this is a cargo plane predominantly.
That sounds like this thing:http://www.reactionengines.co.uk/lapcat.html
BTW M5 = about 1500m/s giving a rocket LEO impulse of 6.5km/s. Going |
down all the time.
- Ian Parker |
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jonathan
Guest
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| Posted: Tue Jun 24, 2008 5:53 am Post subject: Re: ....A Quote From Len Cormier...and yet another rant! |
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"kT" <cosmic@lifeform.org> wrote in message news:poa7k.24$pC2.6@newsfe07.lga...
| Quote: |
jonathan wrote:
Jonathon's on a roll.
|
Am I wrong? I think that's the way the Bush administration
works. They genuinely feel they have a right to use the various
agencies as giant pay-back machines. And giant favor-machines
for the firms they wish employment with...after leaving office.
| Quote: |
Keep your eye on the horizon down there this summer, eh?
|
I love politics, how could anyone not love it?
It's like saying you hate the air we breathe!
> |
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