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Dan Adamo, Dr. Jim Logan, Dr. John Jurist, Tuesday, 11-19-13 November 19, 2013

Posted by The Space Show in Uncategorized.
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THE SPACE SHOW CLASSROOM

Dan Adamo, Dr. Jim Logan, Dr. John Jurist, Tuesday, 11-19-13

http://archived.thespaceshow.com/shows/2125-BWB-2013-11-19.mp3

Your Amazon Purchases Can Help Support The Space Show/OGLF (www.onegiantleapfoundation.org/amazon.htm)

Guests:  Dan Adamo, Dr. Jim Logan, Dr. John Jurist.  Topics:  “Trajectory Challenges Faced By Orbiting Infrastructure Supporting Multiple Earth Departures For Mars.”  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, http://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 www.onegiantleapfoundation.org/amazon.htm.

Welcome to this special Space Show Classroom program with Dan Adamo, Dr. Logan, Dr. Jurist, and myself.  There was no break during this 2 hour 21 minute discussion which at times was very technical.  For those of you interested in missions to Mars, orbiting space infrastructure including depots, Earth & LEO departure points, mission and launch trades, payload issues and trades, radiation concerns, and more, you will find this discussion to be extremely informative and educational.  Guest Dan Adamo took us through the charts and graphs which you can access on either The Space Show Blog or The Space Show Classroom blog ((see http://thespaceshow.wordpress.com and http://spaceshowclassroom.wordpress.com).  Access the document ReuseForMars to follow the MP3 audio transcript. The other document on the blogs is a longer white paper version of the .pdf we used for last night’s discussion.  Dan introduced the topic to us, talked about his tangential work in this area at JSC last summer and the space community interest in orbiting infrastructure, especially fuel depots.  Dan then took us through the .pdf document discussing and explaining each chart and graph.  Rather than report on his page by page discussion, note that Jim, John, and I asked lots of questions per each chart and graph as did listeners by email and later in the discussion by phone.  Some of the main points and take aways from this discussion focused on inclination, launch location, penalties and advantages relating to orbiting infrastructure reuse for Earth departures to interplanetary destinations. For example, Russian launch sites are far to the north and will not be as efficient for Mars launches as sites to the south.  But as Doug discovered when he asked about equatorial launches, they benefit from a boost due to the inertial rotation of the Earth for higher initial launch speed, but otherwise there is no real benefit from the equatorial launch because minimum Earth orbit inclination is imposed by interplanetary geometry.  Another important point had to do with the reuse of orbital infrastructure.  As you will hear, it’s virtually worthless to reuse infrastructure in low Earth orbit to support Mars mission departure, including a depot, unless it can be repurposed for something else other than a Mars mission.  Don’t miss Dan’s explanation of this.  While we talked about Earth departure windows for Mars at two year intervals, we learned that not all these windows are equal.  Here, using the tables in Dan’s document, we were able to see just how unequal the Earth departure windows can be.  We talked a lot about Elliptical Earth Parking Orbit (EEPO) and the relationships with apogee and perigee for our payload departures for Mars.  Later, Dan outlined how we can “store” the cryo in the upperstage of our rocket as kinetic energy in the EEPO shortly after launch, a way to store the cryo energy without having to mitigate boiloff or transfer it between spacecraft.  Much was said about radiation and when you go through the trajectories and see them plotted as Dan has done, we learned that not all trajectories are equal as to radiation exposure.  Other important elements of our discussion that we focused on included the trans-Mars Injection (TMI) and asymptotic Earth departure velocity (v_infinity).  Listener Jimmy emailed us about another paper by a Goddard team that Dan was familiar with and he used some of their data and research.  Access their poster at www.lpi.usra.edu/sbag/science/NHATS_Accessible_NEAs_Summary.png (note you may need to cut & paste the URL in your browser).  As Dan & our Classroom panel went through charts, graphs, & tables, we applied the information to launches Earth departures in 2020 and 2022.  It was valuable to see how the constraints change, not always for the better either.  Note that we started with a 400 KM orbit but later dropped it to about 340 km above earth.  I suspect you will find the changing constraints and parameters to be more than interesting.  Near the end, Doug called in to ask about the reuse of the repurposing orbital infrastructure, including depots, as possible infrastructure for the Moon or a cislunar project.  Not only is this a possibility, we learned that something like the orbits that would be involved in doing this were used for the recent NASA GRAIL Mission.  During our discussion throughout the program, we talked about the two Mars missions now en route to Mars, Maven and the Indian mission Mangalyaan.  Note what was said about Mangalyaan and how it is making use of the type of information we discussed in this program to do a lower energy mission to Mars.  In fact, one of the hot topics of our discussion was the comparison between long-way trajectories and short-way trajectories to Mars, what each means for arrival at Mars, capture by Mars, and the return to Earth and capture by Earth.  The reentry speed coming back to Earth is crucial as these speeds can be extremely fast with lots of heat to dissipate.  Keeping speeds below 12k/s for a human Mars mission is vital.

Please post your comments/questions on our blogs and we will do our best to respond to you.  If you want to reach any of our guests, do so through me using drspace@thespaceshow.com.

Dan’s charts and graphs are here:  MultipleMarsDeparturesR1

To best follow tonight’s discussion, refer to;  ReuseForMars

John Strickland, Tuesday, 1-22-13 January 22, 2013

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John Strickland, Tuesday, 1-22-13

http://archived.thespaceshow.com/shows/1934-BWB-2013-01-22.mp3

 Guest: John Strickland. Topics: Cislunar transportation and economics, SSP, and more. Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, http://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. We welcomed John Strickland to the show to discuss cislunar space development, economics, transportation, SSP, and much more. You can read his latest The Space Review article, “Cislunar transportation: the space trucking system” at http://www.thespacereview.com/article/2221/1. We have also placed on The Space Show blog several images John referred to during our 96 minute discussion. We started the first segment by discussing what is needed in terms of supporting space infrastructure to establish a Cis-lunar space economy. In addition, we talked about heavy lift launch vehicles in general, expendable rockets, the need for RLVs and more. John said there were three basic vehicle needs, a crew vehicle, cargo vehicles, and tankers. At one point he said he would like to see a Dragon model as a tanker. This discussion then went to orbital fuel depots and our guest had much to say on the depot topic. Here, he brought up the idea of a lunar ferry and robotic missions using the RLV. A listener asked him for the biggest challenge to the ideas he was sharing with us and he said money!

     In the second segment, Doug called in and talked about John’s Space Review article per the above URL. Doug had several questions and challenges for John. Another listener emailed in questions relating to John’s trucking system comparisons. Later, Tim called to ask about electric propulsion and this took us to the Falcon Heavy topic, the need for RLVs, etc. Also, John referred quite a bit to Image #2 on The Space Show Blog, the LMO Waystation. We then addressed Space Solar Power (SSP).Guest:  John Strickland.  Topics:  Cislunar transportation and economics, SSP, and more.  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, http://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.  We welcomed John Strickland to the show to discuss cislunar space development, economics, transportation, SSP, and much more. You can read his latest The Space Review article, “Cislunar transportation: the space trucking system” at http://www.thespacereview.com/article/2221/1. We have also placed on The Space Show blog several images John referred to during our 96 minute discussion. We started the first segment by discussing what is needed in terms of supporting space infrastructure to establish a Cis-lunar space economy. In addition, we talked about heavy lift launch vehicles in general, expendable rockets, the need for RLVs and more. John said there were three basic vehicle needs, a crew vehicle, cargo vehicles, and tankers. At one point he said he would like to see a Dragon model as a tanker.  This discussion then went to orbital fuel depots and our guest had much to say on the depot topic. Here, he brought up the idea of a lunar ferry and robotic missions using the RLV.  A listener asked him for the biggest challenge to the ideas he was sharing with us and he said money! In the second segment, Doug called in and talked about John’s Space Review article per the above URL.  Doug had several questions and challenges for John.  Another listener emailed in questions relating to John’s trucking system comparisons.  Later, Tim called to ask about electric propulsion and this took us to the Falcon Heavy topic, the need for RLVs, etc.  Also, John referred quite a bit to Image #2 on The Space Show Blog, the LMO Waystation.  We then addressed Space Solar Power (SSP). He said it would take from $50 billion to $200 billion for a 1GW base load, Ground based Solar or wind system. He then discussed what would have to change about how we do space to see SSP become a reality.  Tim also wanted to know about bypassing the Moon and going directly to a NEO.  John had much to say about using the incremental approach which included the Cis-lunar economic development we have talked about on this program and on other programs.  John’s closing comments with the Teddy Roosevelt statement were important one so don’t miss it.  Please post your comments/questions on The Space Show blog per above.  You can email John Strickland for his materials and with your questions at jkstrickl@sbcglobal.net  He then discussed what would have to change about how we do space to see SSP become a reality. Tim also wanted to know about bypassing the Moon and going directly to a NEO. John had much to say about using the incremental approach which included the Cis-lunar economic development we have talked about on this program and on other programs. John’s closing comments with the Teddy Roosevelt statement were important one so don’t miss it.

      Please post your comments/questions on The Space Show blog per above. You can email John Strickland for his materials and with your questions at jkstrickl@sbcglobal.net.

Below are the images pertaining to the discussion with John.  Note that the “1 page with 2 ferry images” link below opens a document with two color diagrams which will also be part of tonight’s discussion. 

1 page with 2 ferry images

 

Mars Ferry Lander With Writing Corrected

Mars Ferry Lander With Writing Corrected

LMO Waystation

LMO Waystation

LMO Waystation Assembled Horizontal

LMO Waystation Assembled Horizontal

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