Dan Adamo, Dr. Jim Logan, Dr. John Jurist, Tuesday, 11-19-13 November 19, 2013Posted by The Space Show in Uncategorized.
Tags: celestial sphere, chemical rockets, Cislunar transportation, cryogenic fuels, Dan Adamo, Dr. Jim Logan, Dr. John Jurist, Earth departure windows, Earth reentry speed from Mars, Elliptical Earth Parking Orbit (EEPO), Ephemerides, equatorial launch, Grail mission, human spaceflight, inclination, Inspiration Mars, interplanetary payload, kinetic energy., LEO, locus of possible injection points., long way trajectory, Mangalyaan, Maven, nuclear propulsion, Oberth effect, orbit plane change, orbiting fuel depots, prograde orbit, radiation, reusable space infrastructure, short way trajectory, The Space Show Classroom, TMI geometric constraints, trajectory challenges for orbiting infrastructure in support of Earth to Mars departures, trans-Mars Injection (TMI), Van Allen Belts, v_infinity vs. departure date
THE SPACE SHOW CLASSROOM
Dan Adamo, Dr. Jim Logan, Dr. John Jurist, Tuesday, 11-19-13
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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 email@example.com.
Dan’s charts and graphs are here: MultipleMarsDeparturesR1
To best follow tonight’s discussion, refer to; ReuseForMars
Dr. Dmitriy Tseliakhovich, Sunday, 6-9-13 June 10, 2013Posted by The Space Show in Uncategorized.
Tags: aerospace future., ascent trajectory, beam propulsion safety, beamed propulsion and weather, chemical rockets, crewed vehicle, DARPA, distance downrange from launch site, Dr. Dmitriy Tseliakhovich, electric grid, Escape Dynamics, ground stations, heat exchanger, ITAR, launch efficiency, LEO, mass fraction ratio, microwave beam, microwave propulsion technology, nuclear electric propulsion, ocean launch, payloads, Propellant Depots, robotic vehicle, space infrastructure, space weapons, spaceports, SSTO, wireless power transfer
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Dr. Dmitriy Tseliakhovich, Sunday, 6-9-13
Guest: Dr. Dmitriy Tseliakhovich. Topics: Escape Dynamics microwave beam propulsion for launches. 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 Dr. Dmitriy Tseliakhovich, CEO & CTO of Escape Dynamics (http://escapedynamics.com) to discuss their work on making microwave beamed propulsion possible for space launch. During our 1 hour 39 minute discussion, Dr. Tseliakhovich talked about his background and passion for space, including helping to open up commercial space. His work and experience led him to creating Escape Dynamics in 2010 to find a better and more efficient way to space than by using chemical rockets. Dmitriy then took us through many of the benefits of external launch, including a higher specific impulse, better payload ratios, and even the ability to use an SSTO frame for the vehicle. During this segment, we also talked about safety issues and using the possibility of using the technology as a space weapon. During this discussion, Dmitriy was very focused and precise in saying that their systems had to prove out as being safe on all of the issues we were discussing. Next, we learned that the initial beamed propulsion vehicles would be robotic but at some point in the future, eventually crewed launch vehicles would be possible. We talked about their step by step incremental development and testing plan, including starting with suborbital launches. I asked our guest about the probable cost of electricity and support from the existing electrical grid. Our guest had much to say about the cost of electricity, the use of the grid for their power needs & the capability of existing systems to support their needs. He also did not rule out partnerships with utility companies. Listeners sent him emails asking about competition and markets as well as the use of hydrogen for fuel. Our guest was also asked about their heat exchanger, a key component on the vehicle.
In our second segment, Dmitriy was asked about weather issues for launch & we learned that there were concerns and requirements suggesting launching in dry areas would be best. Another listener asked about ocean launch possibilities & Charles called in expressing skepticism, to support chemical rockets, and to raise questions about the high g force, boost stations, and the size of the ground array needed for the beam propulsion launch system. Roger emailed us to ask about orbital fuel depots & beamed propulsion. We then talked about the company timeline & learned about 2015 as a suborbital launch target date. In response to an email about the main challenges, our guest said the challenges to the system were mostly non-technical. John was our last caller asking about DARPA, project financing, fuels, and more. In closing we talked about available internships and the hiring opportunities at Escape Dynamics.
Please post your comments/questions on The Space Show blog. You can contact our guest through his website or by using firstname.lastname@example.org.
Dr. John Hunter, Monday, 2-18-13 February 19, 2013Posted by The Space Show in Uncategorized.
Tags: " SpaceX, alternative space access, chemical rockets, cubesat launch system, Dr. John Hunter, EML1, fuel depots, gas gun demo launch, gas gun installed costs, HARP gun, hydrogen gas gun, impulse launch, Kickstarter., Microwave propulsion, QuickLaunch, spaceports, SSP, terrestrial solar power, Yuma Proving Ground
Dr. John Hunter, Monday, 2-18-13
Guest: Dr. John Hunter. Topics: Hydrogen gas gun technology and capability, microwave propulsion for delivering cargo. 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 back Dr. John Hunter for a fresh look at hydrogen gas gun propulsion technology and capability, microwave propulsion for delivering propellant and delicate cargo, cubesat launchers, and more. During the first segment of our 85 minute program, Dr. Hunter briefly explained his departure from QuickLaunch and the viability of impulse launch with the hydrogen gas gun. He explained how the hydrogen gas gun works which as you will hear is very simple. Dr. Hunter say that with the gas gun, there could be very high payload fractions into the 20′s. Our guest was asked about total costs for the hydrogen gas gun which he referred to as installed costs. Listeners asked him to describe the physical characteristics of the gun and we talked about how many times it could be used without needing refurbishing of some kind. Dr. Hunter also talked about the high pressures and we compared the gun to the old U.S. Navy battleship 18 inch gun from the WWII era. A listener asked if the gun would make a good weapon. The answer was no. John was asked where the gun might be located and talked about Adak & Kodiak, Alaska plus other possible sites in the Lower 48. Listeners then asked if the Alaskan heavier cold air was a factor in using the gun. We learned that the differences between cold air and warm air were minor.
In our second segment, Dr. Hunter introduced us to microwave propulsion launch. He spent some time describing how microwave launch would work and even talked about using consumer quality magnetrons from microwave ovens. In response to listener questions, he talked about demo launches and a Cal Tech student’s PhD thesis on the subject. Later in the segment, our guest was asked about using an impulse launch system as a cubesat launcher given the rise in popularity along with growing demand for cubesats. Our last discussion topic was the use of Kickstarter for funding emerging and startup space projects. Dr. Hunter said it offered real possibilities and advantages for regular people to participate in space companies and projects, but he also issued a warning for people to be alert to not be taken given the lack of oversight with crowd sourcing funding projects in general.
Please post your comments/questions on The Space Show blog. You can contact Dr. Hunter through me at email@example.com.
Tabitha Smith, Gwyn Rosaire, Project Bifrost, Sunday, 12-16-12 December 16, 2012Posted by The Space Show in Uncategorized.
Tags: B4 core, chemical rockets, DARPAs 100 Year Starship Program, fission, Fukushima, fusion propulsion, graphite nuclear rocket fuel, Gwyn Rosaire, HSF to Mars, Icarus Interstellar, ITAR, NASA Marshall Decade Module 2 fusion project, nuclear economics, nuclear propulsion mission, nuclear space technologies, nuclear thermal rocket, Project Bifrost, Russian nuclear propulsion program, Saturn V rocket, Tabitha Smith, tungsten nuclear rocket fuel, White House nuclear rocket policy., Y-12 research
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Tabitha Smith, Gwyn Rosaire, Project Bifrost, Sunday, 12-16-12
Guests: Tabitha Smith, Gwyn Rosaire. Topics: Nuclear propulsion, Project Bifrost, Icarus Interstellar. 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 Tabitha Smith and Gwyn Rosaire to our program to discuss Project Bifrost and nuclear space propulsion. For more information and to contact our guests, visit www.icarusinterstellar.org/projects/project-bifrost. If you are interested in joining Project Bifrost, or have suggestions, please use the “here” email link on the webpage. During our first segment, Ms. Smith started by giving us the origin and meaning of the project name, Bifrost (pronounced BEEFROST). This discussion included Icarus Interstellar and mention of the Darpa 100 Year Starship Program (100YSS). I asked Gwyn about our technical status in having a nuclear thermal rocket and he said we had more of an economic problem with nuclear propulsion than a technical problems. We talked about the lack of a mission for a nuclear rocket and that such a mission would be generated from the White House on down. Nuclear fuel was a topic as new research is focusing on tungsten fuels rather than graphite though our caller Dr. Jim Dewar suggested new opportunities existed with modern graphite fuels. Other listeners emailed in both questions and comments about fuel. Another topic included a discussion about a much larger payload to Mars with a nuclear thermal rocket (NTR) than a chemical rocket so I asked our guests about economic trades as to what would eventually be less costly, multiple chemical rocket launches or the use of a NTR. Using the Saturn V for our chemical rocket, We carried our analysis to the point of including additional launches to cover for a launch failure and also the human factors side in that a shorter trip means less radiation for the astronauts, thus less shielding and potentially less mass. I think you will find this discussion and analysis most interesting, including the NRC equation for astronaut exposure to radiation. In Dr. Dewar’s call, he also talked about the B4 core concept & the progress made with NERVA. We got emails from Bruce in Canada plus other listeners advocating private sector development, a change in ITAR, and the radiation policy changing after Fukushima per this article, www.world-nuclear-news.org/RS_UN_approves_radiation_advice_1012121.html, and the UN Scientific Committee on the Effects of Atomic Radiation (UNSCEAR).
In our second segment, Michael called in to ask about Russian outreach and the Russian nuclear propulsion program. We then asked our guests for the future Project Bifrost plans. We learned of several major issues. One issue centered on U.S. export control. Our guests also noted that the Russian economy was actually gaining in strength and this might cause them to think its better to go it alone than team up with a weak international partner. Other listener emails inquired about time lines for operation. It was suggested that about ten years would be needed for the NTR if all goes well. As for more routine Mars flights, it was suggested that it would take about twenty years after the first human flights to Mars to really have the program operational. We talked about the private sector and our guests suggested that the private sector will play a strong role in developing and using nuclear propulsion. Moving on, the second project our guests mentioned had to do with ablation technology using NASA Ames facilities. The third and final project mentioned was at Huntsville, the Decade Module 2 fusion project at Marshall. During both the first & second segments, our guests talked about Jupiter radiation and magnetic shielding. John asked about this when he called in the second segment. Doug inquired about Dr. Zubrin’s Mars plans & possible trajectories that could be used with the pros and cons for each. Bruce inquired about fuel vibration problems, then Tim called wanting to know about tours at the Marshall facility & the level of power needed for interstellar travel. As we were ending, our guests said we needed breakthrough propulsion or new physics for interstellar travel. Both our guests left us with important closing comments relevant to Project Bifrost & nuclear propulsion for our future with space development. Don’t miss what each had to say as we brought our discussion to a close.
Post your comments/questions on The Space Show blog. You can email our guests through me or through the above website URL for Bifrost.
Keith Henson, Sunday, 12-2-12 December 3, 2012Posted by The Space Show in Uncategorized.
Tags: chemical rockets, costs per Kwh, fossil fuels., fusion power, GEO satellites, hydrogen exhaust, ISP, Keith Henson, laser propulsion, laser rockets, microwave beaming energy, nuclear propulsion, powered sats, Reaction Engines, space solar power, space weapons, SSP economics, Thorium
Keith Henson, Sunday, 12-2-12