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#40 by leovinus on 17 Jan, 2021 19:12
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This Friday's Ocean Worlds panel will have open presentation on a Europa lander concept and an Enceladus orbilander.
https://www.nationalacademies.org/event/01-15-2021/planetary-science-and-astrobiology-decadal-survey-2023-2032-panel-on-ocean-worlds-and-dwarf-planets-meeting-13
Thanks! It was already in my calendar and I am looking forward to it.
PS: As mentioned in the Europa Lander thread, the NASA websites
https://oceanworldslab.jpl.nasa.gov
and
https://oceanworldslab.jpl.nasa.gov/publications/
provide some great lists with background research on Europa, Enceladus et al -
#41 by leovinus on 25 Jan, 2021 18:48
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#42 by leovinus on 25 Jan, 2021 19:05
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A copy of the screenshots and slides used at the presentation of "Calypso: A Titan Sea Probe" at PSDS: Ocean worlds and Small Dwarfs, Meeting #14. Relates to many previously discussed Saturn proposals like ELF, Oceanus and more as well as Orbilander.
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#43 by leovinus on 25 Jan, 2021 19:53
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A copy of the screenshots and slides used at the presentation of "Calypso: A Titan Sea Probe" at PSDS: Ocean worlds and Small Dwarfs, Meeting #14. Relates to many previously discussed Saturn proposals like ELF, Oceanus and more as well as Orbilander.
And as Kraken Mare was in the Calypso study as well, this might be interesting as well https://news.cornell.edu/stories/2021/01/astronomers-estimate-titans-largest-sea-1000-feet-deep Pointer to the journal article in there. -
#44 by leovinus on 29 Jan, 2021 18:53
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Attached a copy of the screenshots and slides from 4 presentations and speakers at Planetary Science Decadal Survey (PSDS) Panel on Mars M8 Open Session, Jan 29th 2021 though I missed the first 10+ minutes or so.
A nice surprise to me was to find SpaceX Dr. Paul Wooster on the panel list. When I followed the presentation, I was struck that the Mars NASA PoR/Vision is so different from SpaceX vision in terms in of <everything>. How to optimize (public) resources for Mars and maximize science, exploration and settlement? Then again, information gathering was one of the goals today.
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#45 by Hominans Kosmos on 02 Feb, 2021 09:15
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Attached a copy of the screenshots and slides from 4 presentations and speakers at Planetary Science Decadal Survey (PSDS) Panel on Mars M8 Open Session, Jan 29th 2021 though I missed the first 10+ minutes or so.
A nice surprise to me was to find SpaceX Dr. Paul Wooster on the panel list. When I followed the presentation, I was struck that the Mars NASA PoR/Vision is so different from SpaceX vision in terms in of <everything>. How to optimize (public) resources for Mars and maximize science, exploration and settlement? Then again, information gathering was one of the goals today.
You can re-watch the recorded live stream for the time being. https://livestream.com/nasem/events/9503099/videos/216814593 -
#46 by Don2 on 05 Feb, 2021 02:35
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I watched the livestream of the Mars M8 open session, Jan 29th. I will post some notes about what was said, and follow that with my own opinions and ideas.
Session notes
1/ The SpaceX Mars transportation system depends upon methane and oxygen production from local resources on Mars. Oxygen can be produced from the atmosphere but methane production requires hydrogen from martian ice.
2/ SpaceX is interested in ice with no more than two meters of overburden.
3/ Using existing data, SpaceX thinks they have identified some locations where ice is highly likely to be present.
4/ SpaceX wants to land between 40 degrees north and south and they think ice is present north of 30 degrees north.
5/ Hydrated minerals are another possible water resource.
6/ To support site selection for their landings, SpaceX would like an ice mapping Synthetic Aperture Radar (SAR) with 1m depth resolution. They would like a replacement for the Hirise camera and the Crism mineral mapper on Mars Reconnaissance Orbiter (MRO), with higher resolution.
7/ The In Situ Resource Utilization (ISRU) community would like a mission landed on the ice deposits to determine ground truth for the remote sensing and to collect geotechnical data to help design extraction technology.
8/ The human exploration side of NASA (HEDS) sees information on dust, radiation, ISRU and landing as their main data needs.
9/ HEDS is currently considering an opposition class mission involving a Venus flyby arriving no earlier than 2035. This would have a short 30 day surface stay with little opportunity for science. They would preposition supplies on the surface before landing rather than relying on ISRU.
10/ HEDS and SpaceX mentioned weather observation and communications relay assets as being useful. Deep space network infrastructure is important for everyone.
11/ Planetary protection considerations are a major issue for manned landings.
12/ The Icemapper mission is an engineering driven mission which would return data by 2030. It uses a radar. The scientists talked about 'making lemonade' out of it. It appears to have international involvement from the Canadians and the Italians. It seems to be the result of a collaboration which evolved outside of normal procedures.
My opinions
1/ Everybody needs a capability to do landing site selection and a replacement for MRO is needed in the next decade. Both manned and unmanned programs need capabilities for ice mapping, mineral mapping, comms relay and a high resolution camera. The MORIE proposal would do a very nice job of meeting everybody's needs, but it is a little over the New Frontiers cost cap which will make it difficult to afford.
https://mepag.jpl.nasa.gov/meeting/2020-04/Day2/15_MORIE_for_MEPAG_post.pdf
However if science, HEDS and international partners all wish to contribute then maybe it is affordable.
2/ In the long term, the human exploration of mars is going to require finding the ground ice deposits and figuring out how to extract them.
3/ There seems to be broad interest in a lander which would drill into the ice deposits to provide ground truth and obtain data for designing extraction schemes. -
#47 by leovinus on 05 Feb, 2021 21:33
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Earlier today, I was listening to Planetary Science and Astrobiology Decadal Survey 2023-2032: Panel on Ocean Worlds and Dwarf Planets Meeting 16. While I had to jump out early, I did follow the discussion by Dr. Carolyn Mercer. I liked the explanation of three objectives (1) autonomy, (2) radiation hardened devices, and (3) communication through kilometers of ice , and maybe a distant (4) sample return, but I wondered why there was no objective "propulsion"?
The Ocean worlds are all far away. Talk of missions that lasts a career-time is mind-blowing. If there was a way to reduce travel time by ~2x (from e.g. 16 years to 8 ) in the next decade then the missions get easier, the instruments can be newer, nuclear is an option again, and you get more science out of it? Sure, "autonomy" or AI/ML is a hot topic but travel time in the solar system seems just as relevant to get more science IMHO. I thought some encouragement for "propulsion improvements" in form prototypes of, e.g., PPPL plasmoid thruster / magnetic reconnection thruster or better version of VASIMR should be a high priority for Ocean world travel and missions. Thoughts?
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#48 by vjkane on 05 Feb, 2021 23:37
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Earlier today, I was listening to Planetary Science and Astrobiology Decadal Survey 2023-2032: Panel on Ocean Worlds and Dwarf Planets Meeting 16.
For those who can't watch these meetings live (I got caught up in another meeting this morning), some of the meetings that are shared on Live Stream are posted here for later viewing:
https://livestream.com/watch/search?q=psds -
#49 by leovinus on 06 Feb, 2021 00:34
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Earlier today, I was listening to Planetary Science and Astrobiology Decadal Survey 2023-2032: Panel on Ocean Worlds and Dwarf Planets Meeting 16. While I had to jump out early, I did follow the discussion by Dr. Carolyn Mercer. I liked the explanation of three objectives (1) autonomy, (2) radiation hardened devices, and (3) communication through kilometers of ice , and maybe a distant (4) sample return, but I wondered why there was no objective "propulsion"?
The Ocean worlds are all far away. Talk of missions that lasts a career-time is mind-blowing. If there was a way to reduce travel time by ~2x (from e.g. 16 years to 8 ) in the next decade then the missions get easier, the instruments can be newer, nuclear is an option again, and you get more science out of it? Sure, "autonomy" or AI/ML is a hot topic but travel time in the solar system seems just as relevant to get more science IMHO. I thought some encouragement for "propulsion improvements" in form prototypes of, e.g., PPPL plasmoid thruster / magnetic reconnection thruster or better version of VASIMR should be a high priority for Ocean world travel and missions. Thoughts?
Maybe you missed the point that she was talking about a specific program.
Grin, I didn't miss that
She mentioned about a dozen of programs and studies but spent more time on that program (was it called "ColdTech2"?) compared to others. That lead to an assumption of relevance and my question above.
For this interested and tax-paying citizen with a PhD and life-long interest in astronomy and space these open meeting are a great way to learn more about the decadal, science objectives and Ocean World plans. And quickly find the knowledge frontier. A few background slides with current programs, scope, priorities, strong and weak points, timelines would have helped me and presumable others.
Looping back, what program or study would the "Oceanworlds propulsion improvements" fit in, and how do the budget, timeline and priority compare with the others above, and do you have a pointer please?
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#50 by Don2 on 06 Feb, 2021 00:48
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I thought some encouragement for "propulsion improvements" in form prototypes of, e.g., PPPL plasmoid thruster / magnetic reconnection thruster or better version of VASIMR should be a high priority for Ocean world travel and missions. Thoughts?
I suspect propulsion technology will be dealt with in some other panel. And I don't think that exotic and very immature tech like VASIMIR and PPPL is suitable for the science program to fund. A completely new propulsion technology like that would probably require a multi-billion $ development program even if it was technically feasible, and the science community doesn't have that kind of cash.
I also think there are some much simpler ways to improve propulsion capabilities. Nuclear-electric propulsion could be greatly improved if there was a heat engine which was matched to the power and voltage needs of an ion thruster. Thermoelectric converters are very good for small, durable power sources, but they are only about 5% efficient at converting heat into electricity. A heat engine like a stirling engine could achieve 20-30% efficiency which means you can get away with a lower mass heat source. However heat engines lose efficiency if you scale them down and for a 100W power source like an MMRTG they aren't worth the trouble. For a 5000 W ion thruster a heat engine makes a lot more sense. (Heat engine is a general name for things like internal combustion engines, jet engines and steam turbines. They are very common.)
Another possibility is a long life LOX/H2 stage. The JWST sunshade keeps that telescope at something like 50K, which is cold enough to keep O2 liquid and cold enough to dramatically reduce the heat flow into a 20K hydrogen tank. One of the instrument cryocoolers on JWST keeps the temperature down to about 8K, which would be cold enough to liquefy hydrogen boil-off.
The problem in both cases is cost. Gravity assist flybys are cheap. Even if they add an extra year to the mission that only means an extra $20 million in operating cost. It is hard for new propulsion technologies to compete with that. -
#51 by Don2 on 06 Feb, 2021 02:05
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https://www.nationalacademies.org/event/02-12-2021/planetary-science-and-astrobiology-decadal-survey-2023-2032-panel-on-ocean-worlds-and-dwarf-planets-meeting-16
I watched the livestream of this session. I will write some notes about what was said, and then follow with my own opinions.
Session report
The session had a lot on programs and processes and not too much on specific technologies.
1/ Headquarters guy expressed the view that any life finding mission should return a definitive yes or no answer and not a maybe. He felt that people should focus on doing great science and not worry about funding or schedule. He pointed out that opportunities to go to the outer solar system are rare. He felt that the science community should consider a deep penetration of the Europa ice shell to reach the underlying ocean. He thought this was hard but not impossible.
2/ The biologist representing planetary protection partially disagreed with that view. She said that there is no accepted definition of 'life' even on earth. She felt that gathering data on life was important even if that data did not produce a definitive yes or no result on life.
3/ Sample return from the outer solar system was thought to be hard but not crazy. (at Enceladus)
4/ NASA doesn't want to have to invent new technologies for every mission. However, maintaining an industrial base to sustain technologies like rad hard electronics is a problem. There is no commercial market for some technologies that NASA wants.
5/ Current spacecraft technology doesn't support mission lengths over 14 years without additional testing.
6/ Planetary protection mentioned contamination from exhaust plumes as an issue for both Europa and the moon. She said the Artemis and CLPS programs on the moon would be a proving ground for planetary protection technologies.
7/ What is the target? This is a key question when deciding on what technologies to fund.
My opinions
1/ I can't disagree more with the Headquarters guy. If you let the scientists build their dream mission you end up with a $50 billion mission that Congress won't fund. Expected budgets are a key constraint.
2/ The cost of maintaining an industrial base to provide the technology for planetary probes is real constraint on missions. For example, the RTG program costs NASA the equivalent of a New Frontiers mission every decade. NASA flies just enough missions to make the RTG industrial base worth the cost. The Europeans do not, and therefore they can't consider any missions beyond the orbit of Jupiter.
3/ There is no point developing technology which doesn't have a big enough market to sustain it. In my opinion the Kilopower reactor falls firmly into this category.
4/ NASA should focus on technologies which are useful for multiple targets, or on technologies needed for missions that are very likely to fly in the next 20 years. NASA should not bother with developing technologies needed to penetrate the ice shell on Europa at the current time.
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#52 by freddo411 on 06 Feb, 2021 02:16
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... snip ...
2/ The cost of maintaining an industrial base to provide the technology for planetary probes is real constraint on missions. For example, the RTG program costs NASA the equivalent of a New Frontiers mission every decade. NASA flies just enough missions to make the RTG industrial base worth the cost. The Europeans do not, and therefore they can't consider any missions beyond the orbit of Jupiter.
3/ There is no point developing technology which doesn't have a big enough market to sustain it. In my opinion the Kilopower reactor falls firmly into this category.
4/ NASA should focus on technologies which are useful for multiple targets, or on technologies needed for missions that are very likely to fly in the next 20 years.
Planetary science as done by NASA would do even better than it does currently if they up'd their cadence by something like a factor or 2 or 4 or 10. The issues that you cite would be much less problematic if the costs were shared over a scale of 100s of flights. The costs to fly per mission could be dramatically reduced if spacecraft were produced in units of 100s instead of 1's. The cost of launch is already dramatically falling ....
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#53 by Don2 on 06 Feb, 2021 03:04
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Yes, a lot more would be possible if Congress would double the budget!
However, US scientists are doing quite well, especially relative to the Europeans or the Japanese.
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#54 by edzieba on 06 Feb, 2021 12:18
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3/ There is no point developing technology which doesn't have a big enough market to sustain it.
I can't disagree with this enough. Both in technology development in general, and in aerospace in particular, technology development and its commercial application are often separated by years to decades. Some even as vital as GNSS are commercially non-viable and only exist because a non-commercial funding source exists (Navstar would never have launched if it was required to be sustained by the market first). Even orbital rocket launch technologies took 50 years to go from technologically viable (Sputnik) to market-driven (Falcon 1). RTGs are another example, and even regular nuclear power took 14 years for commercialisation. Or Chalcogenide semiconductors: Ovonic PCM was invented in the 60s, and commercialised in the 2010s.
Requiring market self-sustainment from newly developed technologies is effectively a halt to technology development. -
#55 by vjkane on 06 Feb, 2021 13:56
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I believe that a bigger challenge for the planetary program is the increase in costs of missions. The two Discovery missions in development, Lucy and Psyche, have life cycle costs almost double their predecessors even taking inflation into account. The Psyche mission, for example, doesn't appear to me to be substantially more complicated than the Dawn mission, but it's costs are projected to be not quite double. (InSight was also more expensive, but much of that was due to a two year delay.) Dragonfly looks to be approximately double the cost of the previous New Frontiers missions (although some of that will be due to inflation - the bulk of the mission operations costs won't occur for 15+ years).The cost of launch is already dramatically falling ....
It is only a fraction of the overall mission cost. For fun, look up the total life cycle cost of the Perseverance mission. Then figure out what percentage of that was the launch cost. A friend of mine used to run NASA's astrophysics program a long time ago and told me that even if the launch was free, he had a hard time paying for the spacecraft.
I would love to see an analysis of the reasons for this. NASA did change the accounting rules for both the Discovery and New Frontiers missions (with good reasons). Are mission teams just acting rationally and using all dollars offered to them?
Or are their trends in mission development and operations that I don't know about that are driving costs?
Or are the remaining compelling missions that can win competitions just more complicated or long lasting (higher operation costs) and with that comes more expensive missions?
With the knowledge available to me, I can determine what mix of these or other factors appear to be driving mission costs up. Perhaps the Decadal Survey in progress with weigh in on this question. -
#56 by Redclaws on 06 Feb, 2021 14:18
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I’ve got a theory on the rising costs thing. Not intended to explain all of it.
The costs of pushing the edge technologically are rising, in lots of areas, but most of all in areas where the edge has been repeatedly pushed. We want to make a better probe than last time. Well we weren’t being lazy last time - we pushed the edge of sensor technology to get there. To beat that, your choices are to wait a long time until the surrounding technological base makes pushing further easy, or push harder. It’s what I call a technological salient issue - pushing any particular thing further and further (without waiting for related and enabling tech to get substantially better first) gets more expensive. The salient you’re extending from the broader level of technology just keeps getting higher, with costs rising accordingly.
Of course that makes me wonder: budgetarily, what are the drivers of cost? They do have breakdowns... -
#57 by leovinus on 06 Feb, 2021 18:25
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I thought some encouragement for "propulsion improvements" in form prototypes of, e.g., PPPL plasmoid thruster / magnetic reconnection thruster or better version of VASIMR should be a high priority for Ocean world travel and missions. Thoughts?
I suspect propulsion technology will be dealt with in some other panel. And I don't think that exotic and very immature tech like VASIMIR and PPPL is suitable for the science program to fund. A completely new propulsion technology like that would probably require a multi-billion $ development program even if it was technically feasible, and the science community doesn't have that kind of cash.
I also think there are some much simpler ways to improve propulsion capabilities.
Thank you for your response. As a Decadal Survey is an investment in the future, I would naively expect some "bets" or small investments in enabling technologies which would reduce the LEO to target transit times by a very significant factor to enable new types of missions. Which is where my question came from. As we all know, it is important here to distinguish between that goal "fast transit" and implementation "whatever solution we can prototype in x time for budget y". Silicon Valley is good on limited-time, fixed-schedule prototyping.
As you mention in a later post, and was also mentioned in the presentation, there is a limited, projected lifetime of ~14 years for missions. Part of it relates to the lifetime of NTGs I understand. I think you are saying that the LEO to destination propulsion studies are not part of the Decadal Survey. Good to know.The problem in both cases is cost. Gravity assist flybys are cheap. Even if they add an extra year to the mission that only means an extra $20 million in operating cost. It is hard for new propulsion technologies to compete with that.
Sure, but just because it is hard does not mean that it should be ignored. On the contrary, when we know that an enabling technology is necessary in the future then I would expect some small investments Silicon Valley style to develop them.
On a humorous note, the discussion of "something new is hard" pops up in every generation. I would think that when we had horse and carriage for transportation and some tinkerers with loud, unreliable, crazy, crappy gasoline cars, plenty of people must have remarked "why bother with that noisy thing when my horse works fine?" and "maybe it will work in the future but not now".
Same discussion for electric cars vs gasoline cars in the last 10 years, or quick DNA/RNA/gene analysis. Who remembers that around the year 2000 the first human genome was sequenced? And now we can do 23andme for home use. Which means that in a few years you can sequence in minutes at home based on a CVS buy. Which nicely loops back to the Decadal because we might have sensors in a few years to sample a natural, transient plume or impact plume during a flyby for DNA/RNA/similarity to Earth-based bacteria which is why I also liked the presentation a few weeks ago on Enceladus et al and plume sampling. -
#58 by su27k on 07 Feb, 2021 01:22
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The cost is rising because fundamentally there is no incentive to reduce cost. NASA is certainly not doing it, and as far as I can see cost is not a factor in these science mission competitions, which means if I propose a mission with 20% of the cost to achieve 80% of the value, I'll lose. Doubly so if I propose to use something with no heritage and/or is new. (And don't get me started on flagship missions which basically have no competition at all, and it's done similar to how SLS is sole sourced to Boeing) This environment is not at all conductive to cost reduction, it's conductive to cost inflation, similar to how EELV is when ULA is an monopoly.
It will take multi-year or decade concerted effort to change this, and it's pretty much hopeless when the insiders have an attitude of "it costs what it costs". -
#59 by Redclaws on 07 Feb, 2021 01:39
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The fundamental reason there’s no money in the decadal planetary science survey for novel propulsion technologies is it’s not for that. NASA has other parts that invest in technologies of that kind. I get it’s something you want, but it’s fundamental tech and there will *always* be an argument for investing program funds in fundamental improvement rather than actually doing something with the technology today.
This literally never ending tension is why there are different organizations and different pots of money. So we actually do some science with the technology we have, *and* work on enabling tech to do better in the future.
She mentioned about a dozen of programs and studies but spent more time on that program (was it called "ColdTech2"?) compared to others. That lead to an assumption of relevance and my question above.
However, US scientists are doing quite well, especially relative to the Europeans or the Japanese.