Broadcast 2626 Dr. Geoffrey Landis

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Guest:  Dr. Geoffrey Landis; Topics:  Venus, cloud cities in the Venus atmosphere, Mars, space settlement, solar system HSF destinations.  Please direct all comments and questions regarding specific Space Show programs & guest(s) to the Space Show blog which is part of archived program on our website,  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 For those listening to archives using 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. 

We welcomed Dr. Geoffrey Landis (see for more information) to the program to discuss Venus, cloud cities in the atmosphere of Venus, settlement, Mars & more.  During the fist segment of our 1 hour 29 minute program, Dr. Landis introduced us to Venus with many of its scientific facts such as a 450 degree C surface temperature, a pressure of 100 times that of Earth which would be equal to 1 km beneath our oceans, and the visibility factor given Venus cloud cover.  He described what one might see on the surface of the planet, plus we talked about the possibility of some sort of life having been on Venus in its early history though no current information supports that.  He said one of the most interesting scientific questions about Venus involves Earth and Mars as scientists want to know why these three planets are so different from one another.  During the first segment, we had numerous listener emails asking about terreforming Venus, wanting to know more about cloud cities proposed by our guest, the atmosphere of Venus, the likelihood of Venus having been hit by a huge rock of some sort early in its history causing resurfacing, colonizing Venus with cloud cities, and more.  During this segment, Kim called from Mexico wanting our guest to compare Venus to Earth and Mars, plus she wanted to know if there were cycler like orbits between Venus and Earth as there are with Mars and Earth.  Dr. Landis described Venus from the ground up to the top of the upper atmosphere. We talked about probes having been sent to Venus, satellites having orbited Venus for more information, and the fact that we don't know nearly as much about Venus as we do about Mars or some of the other planets. 

Dr. Landis described in detail his idea for a floating cloud city about 55 km from the surface of Venus, built on a mega structure but floating above Venus.  He talked about radiation protection from the atmosphere, a gravity almost equal to Earth's gravity and much more.  He talked about airship type vehicles and solar powered craft. Discussing these floating cloud cities was a major part of our program throughout both segments.

Before the first segment ended, Doug emailed in asking about paraterraforming, another listener wanted to know if our guest thought the private sector could develop a floating city settlement on Venus or if there was a business case to close by having a settlement on Venus.

In the second segment, Doug sent in reasons for living on the surface of Venus given our guest had earlier said there probably were no good reasons for wanting to live on the surface.  Dr. Landis did not think that Doug's reasons were convincing and said multiple times in this segment that he did not believe there were any good reasons for wanting to live on the surface of Venus though he did think cloud city inhabitants might want to do an excursion to the surface for exploration or some other reason.  Even so, doing anything on the surface of Venus would require being able to get rid of at least 500 degrees of heat and withstand enormous pressures.  He explained his position in some detail.

Carl sent in a note asking about other possible solar system human destinations.  Dr. Landis mentioned Calisto, the Moons of Mars, possibly even some asteroids.  At one point, he suggested that someday asteroids might be the driver for HSF given their resource richness and insitu resource utilization. 

Another listener bought up the space budget, asking Dr. Landis what would be needed to have a budget capable of doing both Mars and Venus exploration and HSF.  Don't miss his answer.  Mary from Chicago sent in an email asking if Venus exploration, including someday human spaceflight to the planet, required a heavy lift launcher like SLS.  Dr. Landis, while not specifically wedded to SLS, did say a heavy lift launcher would be necessary for doing anything BLEO regardless of the destination.  He was rocket agnostic.  This question took us to a discussion of advanced propulsion.

Regarding advanced propulsion, he said he was working on solar electric which he really liked but it was for cargo transfer.  He noted the slow speed used by this form of propulsion to transit the Van Allen radiation belts saying that for HSF, one must go through the belts much faster.  He said nuclear propulsion was needed, mentioned the fear factor that several have but that we should develop and implement it.

Before the program ended, I asked him if on Venus visitors would have to deal with the same human factors medical issues that exist for long duration spaceflight and Mars.  Interestingly, he said probably not though there is no research on the subject.  Again, he mentioned the gravity at the cloud city would be about .89 that of Earth's gravity.  The thick atmosphere should shield from radiation. These and other characteristics combined would indicate less potential medial risks than typical long duration human spaceflight or going to Mars. Assuming this analysis holds up with more research, I asked our guest if it would make more sense to begin space settlement with a floating cloud city at Venus rather than a Martian settlement since we know the medical risks appear to be less than on Mars.  At one point he mentioned that settlement might be easier on Venus, especially were microbes or some life form found on Mars which might prohibit humans from doing anything negative to impact that microbe or life form.  Finally, don't miss the closing comments offered us by our guest.

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Exploration of Venus and Mars

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18 Jan 2016 Dr. Geoffrey Landis
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