....A Quote From Len Cormier...and yet another rant!

There is one or twi things in the report to pick up on.

Power Management and Distribution. Power management and distribution continues to be a major challenge for large-scale SSP systems. A major feature of the 1979 SPS Reference System was the presumption of very high solar array voltages (e.g., 40,000 volts) that would largely eliminate the requirement for massive power management for the system. The findings of the SERT Program suggest that this feature is not technically feasible for reasons of interactions with the space environment at these voltages and that lower voltages must be used. However, a great disparity exists between the cost of terrestrial voltage converters (about $0.20 per watt) compared to voltage converters in space (about $20 per watt). Studies are continuing to better understand the reasons for these differences and to formulate affordable and effective power management and distribution concepts for large-scale SSP systems. Also during the SERT Program, an option identified during the SSP Fresh Look Study--the use of superconducting power cabling at lower voltages--has resurfaced as one potential solution.

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.

To assure beam safety, "center-of-beam" power intensities have been limited to the general range of 100-200 watts/m2 during the SERT Program for both microwave and visible light transmission (corresponding to between 10% and 20% of the intensity of normal noon time summer sunlight). Good progress has been made and no show-stoppers have been identified - although resolution of potential spectrum management issues associated with power beaming applications with appropriate U.S. and international organizations continues to be an important issue.

This is OK as an intermediate step. However I feel that higher power
levels will be needed in the future. The issue of safety can be
addressed by having a sort failing system and having an instruction to
go to random phase. Random phase is, of course, like banging cadmium
rods in a nuclear reactor. A last ditch safety measure that shuts the
thing down.

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

I used to be able to paste in with Google Translaste. I meant lambda/
4. I went to Google Translate, treanslated "sea" into Greek
(thalassa). Lambda is the normal letter used for wavelength. Why can't
Google give us a proper mathematical font?


- Ian Parker

On Jun 20, 6:17 am, Ian Parker 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

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


The follow-on Timberwind nuclear rocket engine system was though.

Pat

On 20 Jun, 14:11, wrote:
On Jun 20, 6:17 am, Ian Parker 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(-0.8) 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

"Rand Simberg" wrote in message
...


All that died when President Bush canceled the Space Solar Power
program and replaced it with the Vision.

This never happened, you loon. There was no "Space Solar Power
program" to cancel, and it wasn't "replaced" with anything.


I'm sorry, maybe you were distracted by the Impeachment fiasco, but
the language is clear. NASA was charged with ...developing....not studying
the technology needed to start up a very ambitious SSP program.


Executive Summary
NASA'S SPACE SOLAR POWER EXPLORATORY RESEARCH
AND TECHNOLOGY (SERT) PROGRAM

"SERT program" and "SERT effort" refer to both the 2-year Space
Solar Power Exploratory Research and Technology (SERT) program
during FY 1999 and 2000 and the follow-on effort in FY 2001, the
SSP Research and Technology (SSP R&T) program."

The first year Bush had control of OMB they immediately cancelled
it outright. A year later or so came the Vision. Which I documented
here was initiated by a couple of White House jr staffers that designed
the basic outline of the Vision /before/ involving anyone at NASA.
NASA and the 'experts' were brought in afterwards and
.....told... about it.

These jr. political hacks had as their mission to please Pres Bush's favorite
corp...Lockheed et al...and to please Cheney's favorite corp...the US Military.
Their answer....the Vision.

Wake up and take a whiff of how big-time politics work.
NASA was carved up like a turkey while the nation
focused on 9/11 and Iraq.

Maybe that's why you folks seem so mystified over this.
It's the husband that's the last to know the truth....they say.



"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 power2 from
space-based solar energy converters. In addition, during its 2-year
tenure, the SERT program was also expected to \provide a roadmap
of research and technology investment to enhance other space,
military, and commercial applications such as satellites operating
with improved power supplies, free-flying technology platforms,
space propulsion technology, and techniques for planetary surface
exploration."

"The SERT program was established in FY 1999 and continued
through FY 2000 by U.S. congressional appropriation. An additional
appropriation was also funded for SSP Research and Technology
(SSP R&T) for FY 2001. Decisions on internal NASA budget
allocations for FY 2002 were pending during review and publication
of this report."
http://books.nap.edu/openbook.php?re...d=10202&page=1

Now, what changed between 2001 and 2002??? The first
year Bush gained control of OMB they cut the funds off.

And if that program had been continued, if Gore had won, the
projected timeline was.....


TABLE 2-1 NASA's SERT Program-
(MSC) Model System Category Definitions


2006-2007
MSC 1 ~100 kW Free flyer
LEO-to-Earth power beaming research platform
Solar power plug in space
Cryogenic propellant depot
"Mega-commsat" demonstrator

2011-2012
MSC 1.5 ~1 MW GEO-to-Earth solar power satellite (SPS)
demonstrator
Lunar exploration SPS platform
Earth neighborhood transportation system

2016-2017
MSC 3 ~10MW Free flyer GEO-based SPS demonstration platforms
for wireless power transmission,
solar power generation,
power management and distribution, and
solar electric propulsion
Interplanetary transportation system


2021+
MSC 4 ~1 GW Commercial space full-scale solar power satellite




s

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.

Pat

"Rand Simberg" wrote in message
...
Neither a study, or a report, are a "program." And that report was
produced without a single dime of government money. And it happened
long after VSE was announced.


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


I can tell you rarely get past the first paragraph before responding.
Please read a little further~


Statement of John C. Mankins
Manager, Advanced Concepts Studies
Office of Space Flight
September 7, 2000

Mr. Chairman and Members of the Subcommittee,

I am pleased to have the opportunity to speak with you today concerning the
topic of space solar power. During the past 5 years, NASA has examined the
viability of large-scale space solar power (SSP) systems through a series of
studies and preliminary technology research activities.

Very briefly, our results and findings to date can be summarized as follows:

.................................................. ................................................
b. A technology roadmap has been developed that lays out potential paths
for achieving all needed advances
.................................................. ................................................

"ALL NEEDED ADVANCES"

http://www.hq.nasa.gov/office/legaff/mankins9-7.html


For Chissakes, the debate /right now/ between Obama
and McCain is about offshore drilling being 'The Big Answer'.

No it isn't. The 'Big Debate' for this election needs to be
pointed in NASA's direction.

I'm not saying SSP is going to be easy, in fact, the difficulty is a
HUGE benefit to selling it to Congress and the American
people.

WHY?


"We choose to go to the moon in this decade and
do the other things, not because they are easy, but
because they are hard, because that goal will serve
to organize and measure the best of our energies
and skills, because that challenge is one that we
are willing to accept, one we are unwilling to
postpone, and one which we intend to win..."


I'm telling you folks, I've been studying the mathematics
of how things take on a life of their own. Of how to
start something than can't fail to achieve great things.

The power of connecting opposite extremes

1) You /connect/ the most difficult problem possible
with the very simplest idea possible.

Kennedy /connected/ one extreme of the very scary Cold War
with the inspiring opposite of the dreams of technology
and exploration.

With one word....the Moon.

It was a mathematical work of art.

Connect one of the greatest horrors, and the greatest inspiration.
With a simple idea anyone can understand.

Get to the Moon by a date certain.
Somehow, some way, figure it out along the way.

OR

End the looming energy and global warming nightmares, while
inspiring the Trekkian dreams of unlimited energy.
With one easy idea ANYONE can grasp.

SSP by a date certain or else.
Before global warming becomes irreversible
or the oil runs out. Take your choice.

Connect the opposite extremes of greatest harm
and greatest good, with the simplest idea.
Such a goal will benefit (attract) the most people
possible.

And let the final product emerge /as it will/ from
the problem solving system set in motion. This is an
.....evolutionary approach. To sit there and say we have
to have all the technical answers...before...proceeding
is the path to insignificance and failure.

In the end, SSP easily ranks highest, and in all categories
of anything else I can think of... well...next to China
going to democracy maybe.

I can't decide which is easier or has the greater
potential effect.

And here's the beauty, BOTH are converging
towards their own critical points at the same time.
A system's critical point is when change the system
is at it's most sensitive and /a few/ can make
a difference.

With a little luck, during those Olympics the 'winds'
will bring in the famous pollution of coal-fired
Beijing.

And all the world....at once...might become repulsed
at the Olympic Spectacle of ultra-repression and
ultra-pollution.

And the PEOPLE will decide...right then and there
during the most Internet connected global event /ever/
.....what must be done.

All signs point to this being 'The Summer' when the
human race takes it's largest single evolutionary step.
As large a step as from here to the moon.

From a man-made hell, towards a natural paradise.

With a little luck, as little as a simple change of winds
Nature could reassert herself, and rule the world
once again.



Jonathan


"The Missing All prevented me
From missing minor things.
If nothing larger than a World's
Departure from a hinge,
Or Sun's extinction be observed,
'T was not so large that I
Could lift my forehead from my work
For curiosity."


By E Dickinson

s

"Rand Simberg" wrote in message
...
On Fri, 20 Jun 2008 20:43:21 -0400, in a place far, far away,
"jonathan" made the phosphor on my monitor
glow in such a way as to indicate that:


"Rand Simberg" wrote in message
...


All that died when President Bush canceled the Space Solar Power
program and replaced it with the Vision.

This never happened, you loon. There was no "Space Solar Power
program" to cancel, and it wasn't "replaced" with anything.


I'm sorry, maybe you were distracted by the Impeachment fiasco, but
the language is clear. NASA was charged with ...developing....not studying
the technology needed to start up a very ambitious SSP program.


Executive Summary
NASA'S SPACE SOLAR POWER EXPLORATORY RESEARCH
AND TECHNOLOGY (SERT) PROGRAM

"SERT program" and "SERT effort" refer to both the 2-year Space
Solar Power Exploratory Research and Technology (SERT) program
during FY 1999 and 2000 and the follow-on effort in FY 2001, the
SSP Research and Technology (SSP R&T) program."

The first year Bush had control of OMB they immediately cancelled
it outright.

That was 2002,


That's right, that's when he cancelled it.

a year before Columbia was lost.

A year later or so came the Vision.

The vision came out in 2004, a year after Columbia was lost. There
was no SPS program, even a minimal R&T program, to cancel at that
point.


Ya, because he cancelled it just as soon as he took office.
So what? Bush cancelled SSP and gave us the Vision.

My point is we should reverse that. I don't understand
you're point a bit.


The vision was a result of the Columbia loss. Anyone familiar with
the history of space policy knows this. It had absolutely nothing to
do with SPS. To think otherwise is to be monumentally ignorant of
space policy history, or nuts.


Where did I ever say he came up with the Vision because of SSP?
And why does it matter? Except for the cold thought they took
advantage of a tragedy to rape the taxpayers with a program
designed to benefit the /fewest possible/ while waisting the
/most money/ possible.

Your arguments are rather curious. The point is, what's best
for NASA, for America and our the future of this planet.


Kicking around some more moon rocks.

OR

Developing a new energy source?
Slowing global warming?
Ending future wars over oil?
Keeping America independent and
prosperous?


Which is better?




Or both.



Or nothing?


s

"Ian Parker" wrote in message
news:20b49ec4-bcaa-4c15-8cb3-

SSP should save X barrels of oil which will finance it. It is however
heavily dependent of the GOODWILL of government. It will need a lot of
infrastructure to get off the ground.


Right, that's the point. It'll need low cost to orbit first and
foremost. Once we have low cost to orbit, we can have
......ANYTHING.

SSP, colonies, missile defense. Whatever we decide to do
in space will become practical once low cost to orbit
is achieved.

If we were to set the goal as merely 'low cost to orbit'.
People would want to know "what for"?
You have to have a goal that's built around the
'what for' part.

What's the best possible reason? Saving the world
of course. We should want a program to have it's best
chance for success.


It also needs to operate in an environment where the costs and
benefits are shared between a number of nations.


The best way for that is of course 'Saving the World'.



s



- Ian Parker