Are space elevators a viable concept?

Difficult to decide this, but I will be pleased to get to work on the problem if you will be so good as to send me sufficient funds to cover my expenses–say a million bucks.

Mike Brown
NRL (Retired)

Conceptually viable, yes. Technologically viable today? Not yet…materials strength limits won’t allow the structures to be built. Plus, there is the significant issue of cleaning up low-Earth orbits of junk that could damage the structure. Remember that the orbiting junk is moving about 18,000 MPH but the elevator structure is only moving a bit over 1,000 MPH at LEO altitudes, so the velocity differential is huge and the impact of even a small object could be catastrophic.

This really gets down to a strong light material for the cable. Nanofibers may eventually reach the strength / weight ratio required. In any case this is a worthwhile endeavor as it has the potiential to significantly reduce the energy required to lift objects into space.

Viable or not why would you have a need to do it and who really cares.

The more important question is why?

I would think for this to be useful, it would require a pretty good size payload to have an “elevator” going from ground to “space” make any contribution other than a science project. And we have enough of these that have no contributing value to society. In this day and age of a weak economy, I want my tax money spent on technology to develop products we can manufacture, creating jobs and making life better. (I am not looking for the government to get into manufactureing, just seed money to get the research moving.)

Some press Executive Suite for Congress please.

Viable? Yes, but not until the 22nd Century. The space junk issue Alan brought up may even end up driving the schedule.

What are the risks associated with the installation and maintenance? Gravity and weather will be gnawing on it constantly. NIMBY response will be loud. Terrorists will think it a great PR target. Many will balk at the cost versus benefit aspect. Many thought a telegraph cable acorss the Atlantic was just as futile. Let’s do it.

While there are many technical hurdles to overcome, the idea is the best one I know of that can provide easy access to space once it is in operation. I have a feeling that the space elevator will consist of two to four cables, not one, and the power source will be different from the laser being used on the small prototypes that exist today. Unfortunately, we are looking at 50 to 75 years before this becomes a reality, so don’t hold your breath. Actually, the precursor to this should be a geosynchronous space station as the anchor point, and it should have a rotating outer ring for artificial gravity. The eventual offshoot of this work will be a moon tether from near Earth orbit to be used in a similar fashion as the space elevator will be used.

If it can be conceived by the mind, it can be built; maybe not today, not tomorrow, but someday.

Why the laser propulsion or laser battery charging? I thought that the greatest impedement to a space elevator was the strength/size of the cable. The mechanical propulsion seems trivial by comparison.

John

Of course it’s a viable concept, all new ideas where people are thinking on the edge seem impossibly complex and expensive, and most don’t have the support of a large portion of the population, but then when the goals are achieved we wonder how we ever got along without it.
The games should also include concepts for the cable fiber itself which is more of an issue than the elevator cars, nanofiber development would seem to be the secret to the strength to weight ratios required, but who knows?
Nothing would spur cable development like a contest and large prize, much like is now going on now with space vehicles.

And once you get your payload up to geo-sync (actually, you have to be ABOVE geo-sync–your CG is at geo-sync), then what? It’s not like you have anything to do with it once you get there.

What are the “estimated” costs to develop, build, and maintain such a beast, vs. the estimates onh what you’d save in launch costs–assuming the same utilization rates as we currently have. What would the utilization rates have to become to make this cost-effective.

It’s like selling hybrid cars–when you look at the life-cycle cost, you’re at such a close break-even point, it’s hardly worth it.

And *then* you can talk about all these technical chgallenges–like what happens if it should “snap.”

BTW, here’s a simple thought experiment: I keep reading about the HUGE amount of tension at the earth-tethering point. Really? Wouldn’t things actually balance out there, such that your tension is ZERO at the earth’s surface?

Weather conditions would be the greater challenge, even if we could be so efficient in materials design to sustain such a “cord” drive. Propulsion into these elevators would be no problem at all. I did vote NO because of weather challenges in security, but the concept is hard to be said for someone that is not an open option challenge.

Thank you for your time.

Everything else the Buck Roger’s space fiction stories predicted has come true; why not this?

Technology now would not allow. The strength of the track would need to hold up itself (approx 18000 miles long) and the cars. Carbon fiber may meet the challenge some day but, not in my lifetime.

Until a line-of-sight for obtaining a material with the necessary properties is achieved (the strength to weight of existing materials is still an order of magnitude shy of what would be needed), the usefulness of related research is questionable.

It would seem possible with the current trajectory of material science, provided we stay on the curve.

The concern I have is what happens, as mentioned above, when it breaks for whatever reason. In the case of a manned evelvator, how do the occupants save thenselves. Thats a very long drop with a re-entry added. The added weight of life support may preclude humans using the elevator. Then what happens when a couple hundred miles of cable comes spiraling down?

On the other hand, it might be a high tech base jumpers wet dream!

I Love the potential, I’m Concerned about difficulties sending energy through 14 miles of atmosphere, (”Attention, passengers, there will be a slight delay in our 21,000 mile trip to the tethered Space Station due to a small cloud intersecting our energy beam.”) Besides, if we just used the Anti-gravity drive from the UFOs at Roswell, Area 51, it would be unnecessary. LOL (:-))
Why not make it a 50 ft. diameter tube (Tubes are stronger than rods.) we could go up the inside. Eventually We may have the material to build it!

Every thing in “Stationary” synchronous orbit (like the TV satellites) is directly over the Equator. So which North African or SE Asian, or Northern South american country is going to develop the “Tether Base?” Most (except for one or two ) don’t even have a conventional satellite and most of those were launched by someone else.

Viable? Yes, soon. Sustainable? Maintenance, weather, International cooperation and oh how about the terrorist target issue? Perhaps we need to first solve some of our terrestrial problems first. I’d love to see the day our world could do this!

Yes, except I don’t really know for certain. With the extremely high cost of lifting anything out of Earth’s gravity well, they might be. But if we finally get better propulsion, and I mean much better propulsion technologies, then a space elevator could be unnecessary and irrelevant.

Solar winds will cause one heck of a lot of electrical charge. Also, this is going to be one helluva lightning rod! Both are significant problems that must be resolved.

The value of such a system might not be in getting personnel or payloads UP but in getting them DOWN. Just a bit of energy to start downward, then only braking is required - braking system could be powered by generating power from gravity driven downward motion. The return craft need only be a module which flies over to or is otherwise delivered to the cable, attaches to it, then provides a brief downward thrust to initiate descent. No need for flight crew, flight systems, heat shields with their inherent risk (due to lower descent speeds, so what if the return takes a few days instead of a few hours), fuel supply or landing strips to return to Earth as with shuttle. Even the simpler parachute return requires a guidance system and trained personnel to operate, along with the heat shield and its risks, along with risks of impact at landing to experiments as well as personnel. Personnel and experiments could be returned piecemeal instead of all at once, assuming a compact, lightweight return module. Assuming a strong enough cable, the catch might be a compact, lightweight braking system capable of handling/dissipating the energy acquired from braking, although that might not be that big of a problem with a slower descent speed.

Further, it might make sense to start with a descent only configuration, work out the bugs, then progress to a system capable of ascent.

It’s a horrible waste of money and time to even consider this fiasco. We are diverting talent that could be used on a more feasible project. NASA looked at flying up to orbit, I think we should look at that again. We have airplanes that practically go there already.
For a pie in the sky project, how about a floating station? We have superpressure balloons that stay up for months. Build a huge one, like the Space Station, one cell at a time. Once it is large enough, launch your orbiter from there. Resupply can be by more superpressure balloons, or…an elevator? At the current 100,000 ft. (or more) altitude these balloons can attain, you’re a lot closer to orbit. Do you have any idea how much the current rocketships burn to get to that altitude!
Just to finish off this sci-fi story, use hydrogen to lift the balloons and their cargo, then compress and liquifey the gas for rocket fuel. The balloon comes back down fairly empty. The elevator-tether controls the balloons. Just stay out of the jet streams (if possible) and you’re set.

Even if materials strong-enough become available, the issues of security from aircraft, satellites, and space debris may make it impossible. I have read of the concept in science fiction, but practical realities seem to place it way into the future when there is sufficient demand and technology to solve the security issues.

Yes, the space elevator is a viable concept. There are materials development issues to be solved to build one for Earth. We already have materials strong enough to build a space elevator on the Moon or Mars. When the idea of geosynchroneous satellites was proposed, we did not have the capability to put them into orbit, but we developed the capability with time. The space elevator is just a very long geosynchronous satellite. There are problems with selecting a site for the earth station end, for space junk, for weather, etc. We are capable of dealing with these issues if we have the will to do it. Lower cost access to space (in dollars per pound) is needed to make better use of the vast resources of space. This allows communication and TV satellites to be constructed of lighter materials (no high G launch) and to be repaired if needed. A space tug will be needed and has already been concepted. Release of payloads (robotic and manned) from the outer end of the elevator cable will have sufficient velocity to reach the Moon and other diesinations - with proper timing of the release. Are we a sufficiently advanced civilization to take on the challenge?

As for why we should do it, even though we have little direct technology applications resulting from the the Apollo Moon missions for example, the state of satellite powered telecommunications (international communications, satellite TV, the internet), terrestrial observation missions (weather satellites, hurricane observations, global warming measurements), and computer processing capabilities in general, to name a few, would not be as advanced as they are without Apollo. Building a space elevator and solving the inherent engineering challenges could well provide the same sort of impetus for advancements in technology that affect us at a more practical level.

Yes But do you think they would have to be deployed in pairs diametrically opposed?

Yes we will eventually build a space elevator. The technology is not all in place right now however there does not appear to be any show stoppers. Once the system is in place it will open up the new frontier, Space, just like the railroad did for opening up the west for exploration and development. Limitless clean energy from space. We could build power plants that have no environmental impact. When the cost of transport to orbit drops sufficiently many things that make no sense now will make sense. Just like we now manufacture many things in China and ship them half way around the world more inexpensively than making things locally. Imagine zero G hospitals to relieve the strain on a persons heart. Many manufacturing processes will be cheaper in the low gravity vacuum of space. All we need is a cheap way to get there!

Yes, but I believe that a geosynchronous orbit would not be a suitable anchor in space. The satellite would have to support the weight of the cable as well as that of the dynamic crawler (and its payload), and since a satellite is already in a constant state of falling, well…

More realistic would be to assemble a rigid geodesic sphere outside the atmosphere, displaced by the vacuum of space, to float on the upper atmosphere to which a space elevator could be tethered.

Such a cable arrangement would also require management of electricity as encountered in some of the orbital experiments, but which could power the crawler and possibly launch future spacecraft.

In addition, unmanned vehicles flying the jet stream could be tethered to the ground, but these would be more applicable to energy harvesting, something which should be explored first.

If you believe in this “space elevator” baloney, I have a tower in Paris I will sell you cheap. I wonder how many of our tax dollars are being wasted on this nonsense??

No, this will remain tantalizingly out of reach. Its a concept that in its most basic form seems so straightforward that it must be doable. But the reality of suitable materials that may never exist, extremely high space station costs, small payloads, uncontrollable weather, safety, lack of funding, and a myriad of other very real show stoppers, will always keep this idea just short of being realized.

Aside of the materials properties for the cable (theoretically possible) space lift mechanics may be very simple - two pulley design, one on the ground, second up in space and a simple elecrical motor to move a payload, no fancy laser or other complicated stuff.

In a perfect world it would be a viable concept. In ours it would be THE target for every terrorist group looking to make a name for itself.

This would be a more economic method of overcoming the gravity well, problems of static electricity are not problems since you get another source of free energy. Also Robert Heinlein had this idea in the book Friday (some of his other outragous ideas: the water bed and the internet)

This is has been addressed in many sci-fi novels, and in fact, the idea of ground based laser charging of photocells probably came from one of these novels. The engineering challenges are great but not as great as some of these comments seem to suggest. Interesting advances in carbon nano-fiber generation are happening at a rapidly expanding rate. If mankind hopes to maintain a presence in space the construction of these elevators is inevitable. The real question becomes, are the present resources such that we are even going to attempt to spread out from the mother planet prior to some catastrophic event sending civilization back to the stone age?

Unfortunately a space elevator would not change the energy requirements to achieve orbit. It may be able to provide a more efficient method of supplying that energy than current launch practice, once the materials and maintenance issues are solved, but by then technology may have reduced the current inefficiencies to the point of diminishing returns anyway.

Tech and materials are available. Feasible ? Yes
Financials? Not as high as HR3600 or HR2454
Benefits? Many, i.e. disposal of used nuclear fuel rods, hight altitude Solar/Photovoltaic Sail deployment, Lunar H2O 3rd stage delivery just to name a few.

To all commenting here: Lets create collective thinking out of the box & deminish tunel vision. It would make all of us do better. Imagine what we can accomplish if we apply 1/64th of what we know…
Cheers to all.

I’m more interested in how the linked the 2,953 foot cable with the helicopter that was a mile up.

I would sibmit that winds and weather problems as well as material problems would doom a space elevator.

Conceptually it would appear to be feasible, though like most major advances in technology, the road to reality has lots of bumps and dips to manuever. For those who say, “why” or “for what purpose”, the most obvious use would be to establish direct access any continuously functioning “facility” (i.e. such as the space station). Of course, for anything that is NOT in geo-syncronous orbit, this would obviously not work. I liken this to a good example of “thinking outside the box”. All technological advances somehow begin with this first step outside the conventional box. We certainly need to maintain that mindset.

Obviously, materials research would need to be done. In fact many of the comments mentioned point out major problems. However, energy expenditures to orbit would be greatly reduced, not to mention the pollution elimination.

As for those who deride this as a money waster, relax, no significant funds have been spent or are about to be until some of those challenges mentioned are solved - for reasons other than a space elevator.

It all boils down to whether humanity wants to remain Earth-bound or explore the rest of the universe. Maybe some other technology will come along (antigravity?) and make the elevator moot.

Hmm… I read blogs on a similar topic, but i never visited your blog. I added it to favorites and i’ll be your constant reader.

Unlike the helicopter which provided constant upward thrust to support the load, a geosynchronous orbit is an equilibrium point and any downward (lifting) force will pull it out of orbit. Simple physics. The “anchor” in orbit must provide resisting force for a dead lift of the object from a stationary point on the surface of the earth and accelerate it to orbital velocity at the top requiring a huge amount of energy- unlike a traditional launch which takes a more energy efficient path. Millions of dollars wasted for want of a simple analysis using Newton’s laws of motion and the laws of thermodynamics.

This has always been “a goer” but (apart from political will and economic viability) depends mainly on the site chosen (equatorial mountain top?) , materials science advances (monofilaments?) and engineering analysis (linear profile variability to optimise load distributions and atmospheric variabilities).
Motive power source is only a secondary issue and is potentially solvable by several methods.

How much money has passed thru your hands in a lifetime?

Are you a professional journalist? You write very well.
kaufen propecia online

Interesting and informative. But will you write about this one more?

Мдаа..интересный пост. Вот только об этом пишут все кому не лень. Ини что, читают друг у друга новости и своим языком их пересказывают? В сео блогах это особенно заметно. Народ, столько новостей интересных в мире…

Автру +5 за пост. Порадовал

мало инфы. Вы бы хоть постарались написать посто-то. Всё-таки вас читает много народа, да и в поисковике по этой теме вы на первой странице…ай яй яй…не хорошо

Вот огромное человческое спасибо вам за этот блог. Кроме этого поста нашёл ещё кучу интересного для себя. Теперь буду заходить сюда постоянно..Я Ваш читатель

Хотела бы обменяться с вами ссылочкой. У меня блог схожей тематики. Если интересно, то напишите на xizabella24@gmail.com

Хороший пост. Чувствуется ведёте блог с душой, хотя сейчас повально все увлекаются заведением блога, в твитере акка..но по делу, грамотно и интересно мало у кого получается писать, а главное постоянно. Так же всех наших дорогих и горячо любимых дам с 8 марта!!!

Хех, сколько коментариев-то Ну отставать не буду-не сочтите за спам-но сайт понравился. Удачи в развитии.

Понравился Ваш сайт! В рунете вообще мало чего дельного в блогах пишут. Всё стараются друг у друга скопировать посты. Года 2 назад было интересно ходить по разным блогам-видно было сразу-люди старались писать посты..а щас уже только для яндекса и стараются. Вообщем желаю продолжать Вам в Том же духе.
С уважением Ваш читатель.

+1 к предыдущему коментарию..

ООО..давно искал. Забрал в букмарки. Автор, пишите почаще..не забрасывайте блог…Кстати не мешало бы диз поменять.

а тут есть что почитать так держать…не забрасывайте блог.

понравился ваш блог

nice site

Мне понравился ваш сайт. Добавил в букмарки

Хороший пост, бро…так держать!!!

Статья хорошая, только если бы ты оформил её немножко получше (добавил скрин-другой, или какой-нибудь арт) и заголовки сделал - тебе бы вообще цены не было

+1 к предыдущему коментарию…форматирование можно было бы и поудобнее сделать. а так очень понравилось

Да ладно, чего к человеку пристали. Норм там всё с форматированием. Добавил в закладки ваш сайт.

+1 хороший пост

А мне понравился пост

Блог хороший, много хорошего материалла..уж извините что не по теме поста, просто очень понравилось у вас. рад что наткнулся на ваш ресурс.

Ух, сколько коментариев то тут набрасали. Ну отмечусь и я-пост бомба..так держать, молодцом автор!!!

Баянистая тема..уже на куче блогов об этом пишут…Вы бы хоть пооригинальней это всё тогда завернули, чтоб читать интересно было. С уважением ваш читатель.

А мне понравилось, побольше бы таких постов в рунете..Спасибо автору.

Блин, столько написал, а не отправилось…видимо глюк вордпресса. Вообщем забукмартил ресурс

+1 На всякий случай скопировал на жёсткий. Просьба к вам-пишите по чаще

Хороший обзор. Сразу видно что старались, за что и спасибо. Интересно было почитать

Пост супер!!! Ждём продолжения

Приятный дизаин у вас. Не подскажете, где можно шаблоны такие найти? Желательно бесплатно

Интересно, а много времени отнимает ведение блога?

Хороший сайт. Столько много инфы тут нарыл для себя.

Тут глвное не время а качество

Прикольный блог, жаль тормозит загрзка только..видимо хостинг не очень хороший

beautyful

хороший блог у вас. посидел-почитал с удовольствием.

как то все тут, не по тексту у Вас