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A new look!

I haven’t updated the “look-and-feel” of this website in, well, forever.  I’m a guy who always recommends to my friends that they keep their software up-to-date, but I guess I’m also like the carpenter and his own home…

Anyway, we’re now on WordPress 4.0, the current version, and have a new theme for the site.  I tried many of the ones out there (both free and for-fee), but wound up using the 2012 theme packaged with WordPress.  Clean, simple, neat, just the way I like it.  And the masthead, designed by Susan Seichrist, which looked really great with the old site theme, looks absolutely awesome (IMHO) with this new site theme (Thanks again Susan!).  The old site was a bit too condensed and this one is much more ‘airy’, maybe even too much.  I might be slightly modifying some of the .css over the next few weeks as I get more used to this new theme.  Or maybe not :)

I still have a few minor tweaks to do; conference pictures from this year are not yet appearing (those pesky spaces in file names) and several posts can now be made to ‘look better’ with the new theme.

Anyway, hope you like it – and now back to posting – I have a lot of new items for everyone!

On hiatus…

No, nothing is wrong, I’m taking a short break from blogging.  I’m spending this week traveling through central and southern Illinois surveying climate stations.  This is part of a nation-wide project to see how reliable this network really is.  If you want to learn more about it and what I’m doing with it, visit http://www.surfacestations.org.

It’s been much fun and very refreshing.  Just me, the open road, Google Earth and Verizon wireless – what more does one need?  And truly, being able to get away from everything else for a week and visiting people in small towns is good for the soul.  I may make this a yearly pilgrimmage.

A small aside about Verizon data service; it’s freaking awesome.  I have been to the smallest of the small towns (Boody, Assumption, Oconee, Nokomis, etc.) in our state and the data service seems to work everywhere.  It is beyond cool to use Google Earth, live, on my laptop, while I’m traveling…

Anyway, check out what Ben has been blogging at the Official WebSite of the Space Elevator Games; http://www.spaceelevatorgames.org.  You can stay up to date with the preparation for the Games there.

Testing for the Space Elevator Games begins next week.  I fly out to LAX on Sunday and will spend the entire week at Dryden.  I’ll have lots to post then…

Happy Thanksgiving everyone…

Oh my God, the relatives are in town and the holidays ARE HERE!!!

Sorry for the lack of posts this week, but there’s just been no time.  Not much to announce yet either, but that is going to change very soon (with ISEC and, hopefully, the Space Elevator Games too).

I’ll be back posting on Friday Monday.  In the meantime, enjoy the time you spend together with your family over this holiday and don’t eat too much…

And, the following is a special Thanksgiving treat for all you NPR fans…

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(Cartoon from here – click on it for a larger version)

More cool credentials…

In September of 2006, I linked to a resumé on Space Careers for an Aerospace Engineer.  The “cool credential” from that resumé was “Senior Member Research Staff – Assigned to Goddard Institute for Systems, Software, and Technology Research (GISSTR), Project, Super Lightweight Interchangeable Carrier (SLIC) & Space Elevator conceptual design”.

There’s a new resumé on Space Careers for Spacecraft Operations Engineer.  This one has the “cool credential” of:

Research Thesis: Feasibility of a Tethered Space Elevator: A technical feasibility study into the possibility of a large scale orbiting tethered elevator, including analysis of tether material, dimension, structure and survivability in the space environment. The results were then applied to synchronous and non-synchronous tether systems; the perturbations affecting these systems were summarised qualitatively and a study of the orbital debris environment at the relevant altitudes completed.

This thesis was done in the time period of 1998-1999 at Cranfield University in the UK.  Here’s hoping that someday soon people with these skills will not be looking for jobs as Spacecraft Operations Engineer, but rather something along the line of Space Elevator Development Engineer or Space Elevator Operations Engineer.

Globus Cassus – Earth 2.0

There are interesting and wonderful possible applications for a Space Elevator and then there are ideas which just don’t seem to rise even to the level of fantasy.

From the article: “…a brave new world could be built from the remains of our current one. The circumference of this construction– dubbed Globus Cassus, or ‘hollow sphere’ in Latin– would be comparable to the giant planet Saturn. During the multi-million year assembly period, massive hoses would worm deep into the Earth’s fiery bowels and suck liquid metal and magma into orbit through four space elevators sited at equal distances around the equator. This material would be squirted out and transformed into a lattice framework to support the rest of the edifice. As the Earth gradually shrivels and shrinks under this onslaught, its gravity would weaken. Over generations, the skies would darken with the relentless encroachment of the enormous structure above.”

Even though the author (yes, you can buy a book about this) seems serious, I’d put this one down in the “you must be joking” category.

The drawing is from the “Damn Interesting” website, the website where I found this article on (click on it for a slightly larger version).  I highly recommend “Damn Interesting”, it truly has some very interesting articles on all sorts of strange things…

Can you believe it?

I know this has nothing to do with the Space Elevator.  But, I’m a “child of the 60’s”, no doubt about it.  My “guitar hero” was Jimi Hendrix.  If the man had made it this far, he would have been 65 today.

Sixty freakin’ five.  That’s a milestone, man, a milestone…

Rest in peace, Jimi – you were truly a “Guitar Hero”…

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Outside of the Star Spangled Banner, I think his best piece was “All Along the Watchtower…”

There may be a delay…

I have cataract surgery scheduled for tomorrow (Monday) morning.  These surgeries are supposed to be fairly routine now, so I’m expecting a good outcome, but it’s still surgery – you never can be 100% sure.

So, I don’t know how much I’ll be posting over the next few days.  My vision may be well enough to resume posting quickly or it may take a few days for it to “normalize” enough for me to resume.

Anyway, I’ll be back as quickly as I can (and will be jealous of those who are able to be in Luxembourg for the upcoming Climber and Tether workshop).

Thank you…

I’m back, and the first thing I want to say is THANK YOU to all of my readers who took the time to post comments on the blog and/or to email me with their thanks.

It is truly appreciated.

Most of you can imagine how hard this is, but your comments make it all worth while.  This blog is truly a labor of love for me – I receive no compensation for my efforts (nor do I want any – you’ll note that there are no ads on this blog and there never will be) – I only want to see a Space Elevator built.

I think this blog is doing its part by helping to keep up the enthusiasm of the “Space Elevator Crowd” and to introduce the concept to newbies…

So, thank you again for letting me know that my efforts are appreciated.  I will respond personally over the next several days to those who sent me emails and will “comment on the comments” where appropriate.  But I just wanted to say a general “thank you” now to everyone…

A pause…

Posting will be spotty or non-existent for the next couple of days.  I’m off to St. Paul, Minnesota to visit my youngest daughter (attending the University of Minnesota) and to watch my son in the AKA Diamonds Karate Tournament.  Saturday, however, I fly to Salt Lake City to attend and cover this year’s Space Elevator Games and the posting pace will pick up…

More excuses…

So, I’ve only had two posts this week – far below my usual output.  And, as usual, I have a good excuse :-)

Each year around this time, I visit my mom down in Northwest Arkansas.  When my dad retired, he and my mom built their dream house in a retirement community and moved down there in 1989.  It’s right on a golf course.  You can look out their back porch and out onto the 18th fairway.  They would drive their golf cart from their garage, down their back yard, across the 18th fairway and right onto the 1st tee – a real dream for golfers (as they were).  My dad passed away in 2000 and I’ve made a point of visiting my mom at least once a year since then (as have my sister and her husband and my oldest daughter and her husband have too).

Why is this relevant?  Well, shortly after they moved down there, they got interested in computers and bought one – which they used for email, Internet browsing and not much else.  There wasn’t much in the way of access other than a modem and so this is what they used – and this is what my mom uses to this day.  It is so stinkin’ slow that I want to SCREAM!!!  It takes FOREVER to do anything and putting up the two posts I did while I was down there took so long that I just didn’t want to do anymore.  But I’m home now – I kissed my Comcast cable modem when I walked in the door.

They have DSL in NW Arkansas now and I tried talking my mom into getting it.  Lots faster and the price is the same as what she is paying for her modem!  But she doesn’t want to do it – I’m going to enlist the help of the rest of my family members to get her to change her mind – they all use the computer when they’re visiting her too…

So tomorrow, I’ll be back to posting with my usual frequency – and sorry, Ben, that I haven’t put together that list of Utah Universities yet – that is first on my to-do list and I’ll have that done for you in the next couple of days.

Power outage…

As many of you may know, the American midwest has been hit pretty hard by storms over the past several days.  Where I live (western suburbs of Chicago) was no exception.  We lost power for nearly three days, along with our phone and internet service.  Everything is now back up and I’ll be posting again later today – thanks for your patience…

And, I think we’re back…

All of the blog upgrades are now done and everything seems to be working OK.  It’s nice that software developers continually upgrade their programs and provide bug fixes, but it does get annoying at times to have to do these constant upgrades.  This is my third upgrade this year (it’s only June) and I have skipped others that I could have done.  Once upon a time, I was a software developer myself and, having to work with my customers to upgrade their systems, I always tried to make it as painless as possible.  But it’s never completely painless…

So, for the moment, anyway, we’re on the current release of WordPress (2.2.1).  All of the security issues in the old release have been (supposedly) plugged – now we just have to wait for the hackers to find the holes in this release :)  Even the spelling checker works now!  But WordPress still can’t handle whitespace very well.  The pre 2.0 releases handled it just fine – if you wanted a couple of blank lines in your post, just hit the Return bar a couple of times and there you go.  Now, all of the extra whitespace is automatically deleted by the editor, an attempt, I suppose, to force everyone to modify the .css files instead.  Of course that complicates future upgrades…  WordPress has now also made Widgets the preferred method of maintaing the Sidebar (Widgets used to be available as a plugin, now it’s part of core code).  I could have kept all of my old sidebar hacks, but did want to upgrade to the new method, and that, of course, also complicated things.  They have Widgets called “Text Boxes”, basically places where you can plug in HTML code and place them on the sidebar where you want.  But Text boxes can’t handle php.  For that you need a plugin (Execphp), so I had to install that, too.  But at the end of the day it all seems to work and, I hope, future upgrades will be less lengthy…

I’ve also upgraded to the current release of the WordPress theme I use, Blix Krieg.  It is an offshoot of the original Blix theme, one which does not seem to be maintained anymore.  Blix Krieg is maintainted by theDuck, an Aussie who seems like a nice chap.  And the theme works flawlessly.

I’ve also dumped Sitemeter – it was just so unreliable.  It lost several days of statistics for me on more than one occasion, and I’ve long suspected it if undercounting my site visitors.  In it’s place, I’ve installed StatCounter.  Perhaps it’s just a busy day today, but already my site stats are higher than before.

Finally, I’ve also fixed (I hope) my RSS feeds.  I was using Feedburner but discovered, much to my dismay, that somehow I was burning two Feedburner feeds.  Perhaps this is why they weren’t working properly.  I’d like to thank all of my readers who took the time to either drop an comment or email to me to let me know how my RSS feed was working (or not) for them.  Hopefully, this is a solved problem now, too.

As always, if you run into something on my blog that doesn’t work, please let me know.

Now all I have to do is to get the long delayed photo gallery up and running and I’ll be all set…

We’re upgrading again…

I’m upgrading to WordPress 2.2.1 and Blix Krieg 2.2 today, Monday, June 25th.  So, if things look funky when you visit, check back in in a couple of hours and all should be set right.

I’m also re-doing my Feedburner Feed (it got messed up somehow) and adding a few more.  So the results will be, hopefully, “the latest and greatest”.  Finally, I’m dropping my Sitemeter stats – they’re just too unreliable – and replacing them with Feedburner stats.

Thanks for your patience…

RSS – Is it working for The Space Elevator Blog?

For some funky reason, my blog doesn’t appear to show up in my RSS feeds – I don’t know why.  It used to, and then stopped.  It may have had something to do with WordPress’s Feedburner plugin.  I installed it and activated it and… zippo.  So I went back to the old (WordPress) feed, but that, too, is now… zippo.

So, I’ve reactivated the Feedburner plugin and we’ll see what happens.  In the meantime, if any of you use RSS aggregators, could you please send me an email or post a comment on this post and let me know if the RSS feed is working for you (or not)?  I would greatly appreciate it…

Horizons – Book Review

It’s always a treat to find a new author to enjoy, and I think I’ve accomplished that in discovering Mary Rosenblum, the author of Horizons.  This book is about how human civilization might develop and evolve in space, in places which are connected to earth via Space Elevators.

I don’t want to spoil the plot, so I’m not going to summarize the book here – you can find a summary, if you want it, at the Amazon.com site.  But I do have some comments about how the Space Elevator is used in the book.  First of all, Ms. Rosenblum has done her homework on how a Space Elevator might actually function; indeed, she gives credit to Dr. Bradley Edwards “…extensive work on the realities of the Space Elevator…”.  The Space Elevator she envisions seems to be the same one that Dr. Edwards has laid out.  The amount of time it takes to travel between the Earth and the Elevator-based colonies is both realistic and significant in the story.  She also has postulated four Space Elevators, each with their own colony, each run by a different organization/government and all is close proximity to each other, again quite believable.  Finally, she has painted scenarios where the inhabitants of the Space Elevator colonies could actually threaten Earth and makes this fact, too, integral to the story.

Other future possibilities she posits, including hard-wired links in the brain to a future version of the Internet, are both possible and probable.  And she foresees a huge, perhaps even leading role for China in the future, again something that is quite possible.

Her grasp of technology is solid and her extrapolation of how it might evolve was truly well done.  IMHO, however, I don’t think her development of the characters quite matches it.  Some character changes and outcomes were just too convenient, or too jarring at times and somewhat marred an otherwise excellent effort.  However, in the relative scheme of things, that’s a small complaint.

Overall, however, I quite enjoyed the book and would recommend it to anyone who wants to see how a future, Space-Elevator based civilization might develop.

(Click on the thumbnail of the Cover to see an enlarged version)

Site maintenance – Phase 3

It seems that the WordPress development team inadvertently allowed a hacker into their midst and he/she included some unauthorized (and potentially dangerous) modifications to WordPress 2.1.1, the version I had just upgraded to last weekend.

So, I’ve had to scramble and install their new, “safe” release, 2.1.2.  If you’ve noticed anything funky with this blog over the past hour or so, that’s probably why.  Everything seems to be working now – let’s hope it stays that way.

On the bright side, I’m getting pretty good at the upgrade process…

Site Maintenance – Phase 2

It looks like WordPress version 2.1.1 is now up and running.  It took nearly six hours to do the upgrade.  The majority of time was spent figuring out that the WordPress developers, for whatever reason, decided to combine the Posting Categories with the Link Categories.  God knows why – I certainly don’t.  This breaks one of the cardinal rules of system/program development – using one entity for two purposes.  Only a bad end can come to it (and I predict it will).  I’ve had to install some Category hierarchy in order to get my sidebar to display properly.  Stupid.  When I go to post now, all of the Link Categories show up in my Posting Category options too.  Stupid.

On the plus side, the theme that I’m using, Blix, has been upgraded to Version 2.1 by it’s author.  This means that I was able to just load it, put in the changes I’ve made to customize it, and go (once I figured out the Category nonsense).  It’s also been re-titled to BlixKreig (the developer is a German – clever, eh?).

So, I think it’s all working, but I haven’t examined every single post.  It looks like the plugins are working too…

Please, please, please – if you run into ANY kind of problem reading a post, accessing a link, or whatever, let me know.  I want this blog to be problem-free for it’s users.

Thanks for your patience everyone…

Leaving The Planet by Space Elevator

This is a long overdue review of this book.  Leaving the Planet by Space Elevator is co-authored by Dr. Bradley Edwards and Philip Ragan and is intended, according to the blurb about it on Amazon.com, to be “An easy guide to the most exciting development in space travel since the rocket. Stripped of the technical jargon, this is a layman’s guide to the breathtaking developments surrounding the space elevator: a plan to string a 100,000 km from Earth to space, revolutionizing space access.”

The book certainly succeeds in doing this.  Anyone who reads this book, assuming they have at least the intelligence of the average 8th grader and are paying attention, will be able to understand a) what a space elevator is b) how it would be constructed c) how it would work d) why it would work (i.e., the physical principles involved) and e) why it is such a great idea.

Edwards and Ragan discuss everything from the practical issues one will run into in building their version of a space elevator (for example, you need the capability to get 80 tons of parts into space, assemble them together and then lift it all to the appropriate point in geosynchronous orbit), to where it could be actually be anchored on earth.  This latter point is most interesting; the authors specify six locations where the factors of nearness to the equator, lack of storms and lack of lightning strikes favor the location of a Space Elevator earthport; the largest being on the equator and west of South America, but also including three locations in the Atlantic Ocean and two locations in the Indian Ocean.  As an aside, I found the maps of places on our planet which have/do not have storms and lightning strikes over the measured period to be fascinating.

The book also addresses a common misunderstanding; the example of whirling an object attached to a string around your hand (or head) is often used to indicate how/why the elevator cable would remain straight.  This is correct of course, but people often misinterpret this to mean that anchoring the cable to the earth is necessary in order to keep it from flying away into space; as if there are going to be some gigantic clamps holding on to the end of the cable (as the hand is holding on to the end of the string).  I still use the ‘object-on-a-string’ example, but emphasize that it is gravity, acting on the entire cable (rather than on just the endpoint) which is holding it in place; i.e. it really is a cable hanging from geosynchronous orbit.  This book makes this same point in a very easy to understand way.

This is truly a fine book and is a wonderful introduction to the potential of a Space Elevator.  Highly, highly recommended.

Oh, and what’s the difference between this book and the previous effort (The Space Elevator) by Dr. Edwards and Eric Westling?  I think you can summarize it this way; The Space Elevator is more technical while Leaving the Planet by Space Elevator is more current.  I have both books and am glad I do – I refer to both of them often.

Leaving The Planet by Space Elevator is available from Amazon.com and Lulu.com.  For you eBook afficianados, Lulu.com also offers the book in downloadable format.

(Click on the thumbnail to see a larger version of the books front and back cover.)

Update January 20, 2007 – There is a website dedicated to this book too – you can find it here.

Update January 24, 2007 – Well, I stand corrected.  I had written in this post that it was not really necessary to clamp the earthbound end of the tether in order to hold it to the planet – the centrifugal force pulling the tether outwards (and upwards) and the gravitational force pulling the tether downwards would be in balance.  But, as both Ben Shelef and Dr. Brad Edwards have informed me, there IS a slight, outwards (upwards) pull on the tether; otherwise when the climber was put onto the ribbon, it would have the effect of pulling the ribbon downwards.  So, to correct my earlier posting, yes, there must be a clamp holding the space elevator to earth; otherwise the tether will fly away from the planet.  But it’s not much – only about 20+ tons worth (in a system massing more than 1400 tons).  Once a 20 ton climber is placed on the ribbon, the system is then, essentially, in balance.  I apologize for my mistake…

Comments and Spam – Round 2

Well, the Math plugin turned out to be useless – I received as much Spam after I plugged it in as I did beforehand (though I don’t understand why).  I’ve turned on the Akismet Plugin and, so far anyway, it seems to be working.  But I don’t know if I like it because I still have to sift through the Spam it blocked to see if there are any comments that should have been posted.  I’ll hope that people post a bunch of comments in the next week or so (hint hint) and see if they all get through.  if some of them get erroneously blocked (and I have to manually release them), then maybe I’ll look for yet another plugin.

Sigh…

Comments and Spam

I’ve just added a Spam filter to my Comments. I now receive several hundred Spam comments each day and am getting tired of having to sift through them all to find the occasional, “real” Comment.  The filter I’m now trying is entitled “Did You Pass Math?”, asking the user for the answer to a simple math question.  The location of the answer box is a bit clumsy, but doable.

I’ll see how this works.  If someone has a problem with it or can suggest a better WordPress plugin, please email me at Ted AT SpaceElevatorBlog.com.  Thanks…

Cool credentials…

This is cool.  There’s a resumé on Space Careers for an Aerospace Engineer which reads, in part, “Senior Member Research Staff – Assigned to Goddard Institute for Systems, Software, and Technology Research (GISSTR), Project,  Super Lightweight Interchangeable Carrier (SLIC) & Space Elevator conceptual design” – this was from his/her posting at ISR.

I was a software guy for most of my professional life, and did some pretty cool things, but nothing like this – I’m jealous…

Dr. Gregory Benford – Space Elevator Skeptic

I was at the Skeptics Conference this past weekend – the subject was Global Warming.  One of the presenters was Dr. Gregory Benford (Physicist and prolific SF writer) and his topic was “things that we could DO to solve the Global Warming problem.”

During his talk, he dismissed fusion as a “solution that is 50 years off and always will be.”  Another possibility he mentioned, but dismissed as being too expensive, was space-based, solar power panels.  During the Q&A period after his presentation, I asked him why the solar power solution was too expensive – was it the lift cost to get the hardware into orbit or was it the cost of the hardware itself?  He replied that it was the lift cost.  I then asked him that if there was a much cheaper way to get this stuff up to orbit, would that change the equation; i.e., would this be now a viable solution – he readily agreed.  I asked him what he thought about the idea of a Space Elevator.  He replied that it would be developed “after fusion power”, getting a nice laugh from the audience.  Sigh.

After his presentation, I spoke to him and asked what he specifically thought was unrealistic about the possibility of a Space Elevator.  He replied that it was “tension” and “stability”, but did acknowledge that some work was being done with “carbon fibers.”  I didn’t have a chance to speak with him anymore – people wanted to talk to him about his solution to global warming and I didn’t want to monopolize his time with my pet subject.

Dr. Benford is a physicist and I respect him tremendously.  He has a reputation for thinking outside the box and I was disappointed in his dismissal of the Space Elevator idea.  On the plane ride back (the conference was in Pasadena, California and I live near Chicago) I spent some time thinking about what to do about this.  I think what I’ll do is send him a copy of Dr. Edwards book and the new LiftPort book.  I have no idea if he’ll look at them or not, but I think it’s worth a shot…

A Plea for Help with Ruby on Rails

Normally I don’t re-post anything off of the LiftPort blog – figuring that if someone is interested in it, they can just subscribe to it directly.  However, Tom Nugent has posted a request for help in a web-based database application that perhaps some of my readers might be interested in contributing to.  Following is his complete post;

“I’m working on setting up a database-backed web application for outlining space elevator research questions, as part of the work we’re doing this summer with our interns. (I hope to talk about the project in more detail in a future blog post.) I’m not a web programmer by training; I’ve done bits of PHP and database design here and there, but not enough to be an expert. I’m using Ruby on Rails for this task, which has certainly boosted my productivity relative to using PHP. But I need to get a lot more done in a very short time (think: within a week), hence I’m sending out a plea to our community at large.

If you’re a programmer who has strong experience with Ruby on Rails and are willing to offer suggestions, feedback, discussion, and/or improvement of code related to furthering the space elevator project, please get in touch with me. My email address is ‘tom DOT nugent AT liftport DOT com’ (is it hopeless to think that this kind of mis-writing of an email address will fool spam address-harvesting bots?). Thanks!”

So, if anyone can help him out, please send him an email…

Feersumm Endjinn

Over at BillSaysThis, he posts a review of Iain M. Banks 1995 book Feersumm Endjinn.  This SF novel, favorably reviewed by most readers at Amazon.com, revolves around descendents of a civilization that had built a Space Elevator.  Be warned, this book is supposed to be fairly “heavy reading”, especially for a SF novel.

Project #83 on my To-Do list…

Ex Machina

I’ve never been a fan of computer role-playing games; I’ve got nothing against them but they’ve just never interested me enough to “float my boat”.  But I’ve found one that I might give a try; In Tri-Stat: Ex Machina (Guardians of Order), Bruce Baugh has put together roles for a future civilization based on and around a Space Elevator.  I’d hazard a guess that it probably has many similarities to Babylon Five (my all-time favorite SF series); permanent inhabitants of a futuristic structure interacting with each other and other, transient characters.  If I could just find the time…

And over at LiveJournal, Malaclypse the Seeker has his own version of these roles.

Earlier mention of Rep. Mollohan and ISR

While perusing the July, 2004 issue of Discover Magazine, I found this paragraph.

The office of the world’s leading space elevator designer is across the street from the Foxx Pawn Shop in the somewhat frayed downtown of Fairmont, West Virginia. The little mining community of 19,000—hit hard by the 1990 Clean Air Act, which made the local sulfurous coal a tough sell—aims to become a high-tech hub, helped by lashings of funds from Congressman Alan Mollohan, a ranking member of the House Appropriations Committee. Edwards is director of research for the Institute for Scientific Research, a four-year-old technology development house headquartered here in a new, cool, rather spartan office building. The space elevator is the most prominent of a dozen projects on the institute’s agenda.

This is the earliest mention I’ve found, so far, of Rep. Mollohan’s funding of ISR.

Affordable to the Individual Space Flight

This web site has evidently been in existence for some time (since 1998?), but I just stumbled across it today.  It purports to describe a concept where with “today’s technology”, humanity could build a system which would make space flight much more affordable.  The key concept is a “Earth Orbiting Elevator”, a skyhook.  The author doesn’t describe what the “Elevator” would be made of, but it’s an interesting site nonetheless.