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Space Show Webinar, Sunday, 5-25-14 May 24, 2014

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Space Show Webinar, Sunday, 5-25-14

Partial Gravity, Tethers, Artificial Gravity

Joe Carroll, Dr. Jim Logan, Dr. John Jurist

http://archived.thespaceshow.com/shows/2249-BWB-2014-05-25.mp3 — Audio only

http://vimeo.com/channels/thespaceshow — Webinar Video

Guests:  Joe Carroll, Dr. John Jurist, Dr. Jim Logan.  Topics:  Partial/Artificial gravity, tethers, NASA, HSF & more.  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, https://thespaceshow.wordpress.com.  Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See http://www.onegiantleapfoundation.org/amazon.htm.  For those listening to archives using live365.com and rating the programs, please email me as to why you assign a specific rating to the show. This will help me bring better programming to the audience.  To see the video broadcast for this webinar, please go to http://vimeo.com/channels/thespaceshow.  Note that the audio only & video archive will be posted at the same time once the video is edited, processed, and uploaded to the Vimeo Space Show channel.  Joe Carroll has presentation material on The Space Show Blog which he referred to throughout our discussion so you may want to download the material or have it available to you when viewing the webinar.

We welcomed back to the program Joe Carroll to follow up on his May 2011 Space Show Classroom program on the same subject.  Our panel members included Dr. John Jurist and Dr. Jim Logan. All of us were part of the May 2011 program on this same topic.  During segment one of our 2 hour 10 minute webinar, Joe Carroll went over his background, interest, and experience in the subject dating back to 1981.  Joe discussed his recent work and updates including his concerns for the rotation rate, Coriolis effect & the absence of any substantial progress in the area.  He directed us to Slide 2 & the specific language used in the 201 US National Space Policy introduction.  Our guests talked about missed opportunities by NASA & others to do the essential research needed to confirm the gravity prescription for humans.  Our guests also talked about the amazing amount of unknowns regarding the effects of microgravity or Zero G on humans as we are a 1 G species.  The issue of space settlements came up & I asked our guests if we were jumping the gun pushing settlements when so much of the human factors work remains unresolved and even unknown.  Joe talked about two extremes in the approach to settlements.  He said one extreme was to simply prove issues by walking.  That is, just try it.  The other extreme was to do “endless research and studies,” a critique often mentioned by space advocates.  Jim pointed out that essentially knowing nothing about the Gravity Prescription despite 53 years of human spaceflight experience doesn’t rise to the definition of “endless research and studies.” Apollo was the walking theory for the most part.  Our guests then talked about NASA plans for an outpost as compared to a settlement, specifically for the Moon.  During this segment, we received several listener emails which the guests responded to.  During this time, Jim continued to state that it was essential that we know at least the basic outlines of the gravity prescription for humans for long duration interplanetary spaceflight.  Our guests talked about the ISS and the role it could play in supporting gravity research.  Joe continued to discuss more of his slides and our panel members had much to say about the discussion. Toni called at the end of the segment to ask about 1 RPM spin rate and mentioned that SpaceX said it wanted to go to Mars by 2020.  Here is the article Tony referenced:  http://www.dailymail.co.uk/sciencetech/article-2634046/Elon-Musk-says-SpaceX-making-progress-Mars-colony-2020-plans-sell-tickets-500-000.html.

In the second segment, we decided to hold the listener emails until the end of the broadcast to allow Joe time to finish his slides and state his conclusions.  We started off with Slides 6, 7 & 8.  Joe progressed to talk about the inflatable tunnel, some of the technical aspects including specs and diameters and why one was better than the others.  Joe continued taking us quickly through the slides but for those interested in the details, pay close attention to them or contact Joe as his email address is on his presentation material.  Joe spent some time this segment talking about doing Gemini-like tether experiments and he also referred us to Robert Walker’s work.  Robert is a Space Show guest from the UK who has done excellent work on the issue of partial gravity based on Joe’s work with tethers, etc.  Check out Robert’s paper at
http://www.science20.com/robert_inventor/crew_tether_spin_for_artificial_gravity_on_way_to_iss_stunning_new_videos_space_show_webinar_on_sunday-137070.  Don’t miss the links to the tether spin videos in his paper.  The subject of rocket reusability came up and again, Joe and our guests had much to say about this so don’t miss it.  Also in this segment, there was more focus on spin rates.  Joe took us through is conclusion slide which is Slide 20.  He talked about the difficulty in selling space as the next stuff and said one never launches with cutting edge hardware.  We then fielded second segment listener emails on a variety of topics, then we talked about people wanting to go to Mars with the just do it concept mentioned in the first segment.  Several Dr. Zubrin comments were used as illustrations along with SpaceX plans to do Mars by 2020.  All of our guests said there was a significant difference in a short trip to the Moon with Apollo where the decision was made to take the risk for a few days but that going beyond LEO for a long trip to Mars for example was a totally different thing altogether.  Jim used long duration sailing voyages as an example of how the issues for the crew once the long duration trips were started turned out to be very vastly different than for short, easy, turnaround ‘sortie’ voyages. Once transoceanic voyages were attempted it didn’t take Captains, crews or their respective patrons long to realize long duration voyages came with radical new levels of complexity and increased human risk.  We talked more about tethers as well.  Jim made the point that the average time spent on the Moon per Apollo lunar moonwalker was only 2.06 days, a woefully inadequate time to ascertain increased risk.  Joe also talked about the possible study & use of 0.06 G as explained in Slide 8.  I asked each guest for their concluding remarks, starting with Dr. Logan.  His take away was that it is critical to know the gravity prescription. Dr. Jurist was next saying there was no useless research and that gravity research may very well benefit us here on Earth in ways we can’t even imagine at this time.  Joe summarized his concluding thoughts per his last slide, talked about his possible plans to be more proactive with his work and suggested easy experiments that could be done with a Dragon and the spent first stage even on an ISS mission.

Please post your comments/questions on The Space Show blog above.  You can reach all of the guests through me but as stated earlier, Joe lists his email address on his presentation material.

Partial Gravity IAC2010 Presentation revised 2014May22

DesignConceptsForAMannedArtificialGravityResearchFacilityForIAC2010Sept14 rev 2014May22


1. DougSpace - May 28, 2014

I appreciated the discussion re: whether a gravity prescription could be established by directly going to the Moon and doing experiments there.

I don’t recall any estimates on the Show as to how much the variable gravity station would cost nor how much it would delay going beyond LEO. It seems to me that there has been a fair degree of consensus that it is time we start going beyond LEO so a variable-gee station might be a political non-starter. Also, if we are unable financially to go to the Moon for 6 or especially 12 month rotations, then it should make one wonder if we will ever be in a financial position to go beyond LEO.

I think that this logic assumes that the costs of launch and cis-lunar transportation will never be able to be reduced. Hence, going to the Moon will always be 5-6 times what it costs to send people to LEO now. I personally don’t believe that one can just assume that indefinitely especially with what SpaceX is doing with both the F9R and FH.

Also, I didn’t feel like enough consideration was given as to extended animal studies using tethered systems. I could imagine that such an experiment would cost a fair less, perhaps those funds could be found sooner than a full-on crewed partial gravity station, and could give us an initial gravity prescription. If it were me, I would place a rotating thetherd experiment in a co-orbit with the ISS, and have three tethers from the center of rotation measuring 1/6th, 3/8ths, and about 0.7 gee. This ought to give us the initial shapes of the biological response curves.

Alan M - May 29, 2014

Dr. Doug! Keep up the good work. I agree with everything you said and Joe Carroll’s work on artificial gravity is great.

So. . . as far as gravity is concerned – we can surivive on the ISS for a year. So. . . the Moon should be longer, say 2 years and Mars should be even longer, say 3 years. So Zubrin is right. We can go to Mars with some kind of gravity, whatever it is. It gets the job done. I’m not talking about cities in space. We will be doing outposts first and we know what we need to know to accomplish outposts. Then we learn if we can survive long term. Not sure why we couldn’t afford to rotate crews at outposts in the early years. If not, then how are we supposed to afford settlements????

No need to test Moon gravity except on the Moon, its in our backyard. So testing Mars gravity perhaps. How about Mars gravity Bigelow station so astronauts could stay for years, if they want.

I know that gravity and the other physical factors are huge. But you engineer with what you know and go! You learn the rest on the journey. If you wait til you know everything, you’ll never go, and why would you need or want to?

Alan M

The Space Show - May 31, 2014

Alan, I believe there are two important take aways from you post: 1): For all those that care about our space program and its future, including and specifically human spaceflight, we can count our lucky stars that you are neither a mission planner or space policy maker and that mission planners and policy makers will never ever listen to a word that you and your likeminded “true believers” preach in the space community. 2) That had you been one of my graduate students in college, you would have either flunked or had to demonstrate that you could develop opinion based on fact and solid engineering, life sciences, and related foundations, traits you do not demonstrate in your blog posts. That said, your posts are most instructive as they illustrate a problem we frequently address on many Space Show programs. The problem I am talking about is fantasy thinking, not evidenced based thinking. I certainly encourage you to continue listening to Space Show programs but also do some real research and learning. It will only serve to make you an effective space advocate rather than a guy hanging out in la la land. Take care and all the best. Above all, keep listening and learning.

Alan M - June 1, 2014

So, I guess I wll keep my ‘aliens are real and live among us’ comments to myself. (joking!)

But seriously, I guess I need to get my comments cleared by the ‘perfect research paper comments nazi police’ or something. I made a glib comment on your blog. (note to self, no fun is to be had on the space show blog) I didnt present a paper. If you dont want people to comment on your blog, why have one?

Not really sure what I said that was so outlandish. I didnt suggest we send people to Mars in a paper bag.

We sent astronauts to the ISS with the information we had and have learned and adjusted as we went. They were human guinea pigs. Some have health issues because of it. They would probably do it again. No regrets. Its part of the job and they all accept it. Folks are beating down the door to do it.

As one of you guests has said, we need to start taking risks in space or why do it. It truly is a waste of money, otherwise.

I’m sorry that I and some of your other listeners don’t live up to your expectations. Guess I could wait to comment til I have five Phds and every comment can be as long as a novel with foot notes.

God Bless

Alan M

2. DougSpace - May 28, 2014

Yes, I too was intrigued by Joe’s description of putting a box over his daughter’s head and then driving in a slight circle. It seems like an experiment that anyone could do…just don’t put the box over your own head while you’re driving, OK?!!

3. jimjxr - May 28, 2014

Just listened to this segment.

First I don’t think we should take the news from Daily Mail too seriously, it’s not a reliable source of information. In this case it’s just mixing up different things together, on 5/16 Musk gave a short talk at ISDC where he mentioned they’re making some progress towards the Mars goal but not as fast as he liked, 2020 did not come up anywhere in the talk. He did mention 10 to 12 years from now as the first MCT flight to Mars in this interview: http://www.parabolicarc.com/2014/02/05/elon-musk-interview-2/, so it’s really middle of the 2020s, not 2020.

Second, I think NASA is doing some a lot of the things suggested in this talk, just not as fast as we’d liked, but I believe fast enough that a manned Mars mission in the mid or late 2020s is not out of the question. On the manned side, there’s the one year mission on ISS next year, a round trip to Mars takes less than 2 years, so this is already pretty close to what is needed for a Mars mission, and they have some time to expand the one year envelope after this mission is done. On the animal side, next SpaceX cargo flight will bring mouse to ISS for microgravity experiment and I think more mouse experiments are also planned: http://www.nasa.gov/mission_pages/station/research/news/rodent_research/#.U4N0Xvk7tEE

For fast sample return from ISS, NASA is funding this: http://www.parabolicarc.com/2014/05/10/terminal-velocity-aerospace-selected-nasa-sbir-award-iss-sample-return-system/. For inflatable, we all know Bigelow will have a small module that will be integrated to ISS next year, this hopefully will give NASA a chance to evaluate the effectiveness of inflatable and may be expand its use in the future.

4. Tom Hanson - May 26, 2014

Thanks for this outstanding classroom! Joe Carroll replied to a caller by reporting on his experiments with an automobile to simulate a tether operating at 1 RPM. This experiment could be conducted by anyone with access to a suitable vehicle and a circular track. Existing oval race tracks subject drivers to “artificial gravity”, but the amount of force is not reported along with velocity and other runtime parameters. (th)

5. Space-for-All at HobbySpace » Sunday webinar on artificial gravity via rotation with tethers - May 24, 2014

[…] Space Show Webinar, Sunday, 5-25-14 – Thespaceshow's Blog […]

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