- But at this point, I'd like to turn it over to Knicole Colon who's going to talk a little bit about the Flagship issues related to the Flagship recommendations. - [Jennifer] Michael Meyer this is Jennifer Gregory. Sorry to interrupt. Just wanted to let you know that we did make you a cohost. So if you have the participant list open and given that this is a little bit more of a fluid conversation today, you may see some raised hands just wanted to let you know. I know we're using Q and A tool folks should definitely put their questions there, but I wanted to make you aware. - Thank you. - Yeah, on that note, Chas has had his hand raised for a while. I don't know if that's still-- - [Chas] Yeah and hi, this is Chas. Hi Keivan? Hi Bruce? Bruce you mentioned something that, you know, the non-mentioned of things that at the high level does not mean a disendorsement. I'm thinking specifically of EPRV and I think within NASA headquarters at least, the fact that EPRB received no mention, or even the sub endorsement of the exoplanet strategy report is being seen as a negative within NASA headquarters. And there's quite a lot of head scratching as to what to do about EPRV. So I'm not, you know, the dye has been cast, but I'm not sure how you guys could talk to headquarters and reassure them that indeed you guys do love EPRV or whatever, but it certainly causing some heartburn, I would say. - Any comments? Bruce-- - Yeah, we're no longer a committee, right? I mean, I can make statements personally, as a scientist and quarters should kinda know how to interpret these reports. I would tend to say, that it'd be weird for a $10 million initiative to get recommended in the decadal survey. And as we're saying there's a full-fledged National Academy report that's given phrase that says this is important. So yeah and these documents shouldn't be treated as if they're carved in giant stones and revealed by ancient space gods, right? They're part of an ongoing scientific dialogue. And if the community thinks there's something that needs to... The report says, "Hey, let's go characterize some earth, "like planets." The community should figure out how to do that and what's needed to make it happen. So, yeah it feels like that's over interpreting to me. - Yeah and I would just kind of say again, Chas, you know, it's a fair question. I would just say again, the Exoplanet Survey Strategy, they have a plan to Science Strategy Report. It's a full-fledged National Academies consensus study document, and you know, period. And in terms of sort of the scale and granularity of the programmatics that we speak to in the decadal, you know and again on the one hand we were looking at pathways to multi-decadal grant questions. We did also right? Speak, I think strongly I hope, to the importance of balance across the portfolio. And that includes for example, investments in laboratory Astrophysics, mid-scale investments in instruments, instruments that serve the achievement of the larger scientific priorities, right? I don't know does that help connect the dots maybe? - I agree with everything you guys have said that it should be read as this remains an important thing to do. I'm just commenting on some of the headwinds. I think headquarters is finding as they weigh different priorities going into the future. - And I think this does echo one of the questions in the Q and A tool, but maybe we can pivot to Knicole addressing some of the other questions on the Flagship issues. - Yeah, thanks for that segue. So just as a recap of course, so we have the Q and A tool. So if you have questions that you want to ask relating to not just Flagships, but as a reminder of the point of the... Or one major aspect of the decadal report was to implement the next Flagships, the next observatories. So part of this was about the development of a mission, a Great Observatories Mission and Technology Maturation Program. So I do encourage questions about that as well. And then the report recommended that the first mission to partake in this program is a large six-meter class infrared optical-UV space telescope. So, you know, feel free again to populate the tool. I think at this point there are some questions that are related. So I'm just gonna dive into the tool here. And so the top rated one right now, which we'd like to ask Bruce and Keivan is that Astro 2020 gives little mention or attention to the uncertainty on eta Earth, which is a major risk to... They call it by name LUVOIR/HabEX-like mission, let's call it, you know, a six meter class mission, either way the recommendation from the report. So how's NASA going to address essentially the uncertainty on eta earth and what if a Kepler 2.0 is needed? Funding could be hard to justify and given this fact, so I guess any comments on that from Bruce or Keivan. - Bruce, you go first. - Yeah, sure. And again, one should know there're different capacities, one can talk in passing the committee report versus talking as an individual scientist actually I have an individual scientists hat to put on for when I wish to speak as an individual scientist, which perhaps I will wear it for purposes of this, but, you know, right? We all know there's significant uncertainties about the remain about the eta-sub-Earth number. And we also all know that uncertainties about the exact number of 0.7 to 1.5 earth radius planets from .7 equivalent to 1.18 equivalent of whatever your favorite box is post Kepler pale in comparison to our enormous uncertainty about the evolutionary pathways that planets took to get, took planets of that size to exist and how that bears on the probability that they bear life or have particular atmosphere chemistries or solid surfaces, or aren't made out of cheese or whatever. We're never gonna resolve those uncertainties to the point where you can define missions to three significant figures. And in fact, the only way to resolve those ends, those big uncertainties is to launch the damage and it gets them spectra of the actual planets to measure what's out there. So there certainly exists a risk that the mean number of planets expected to be produced by a given mission might drop or increase by 30 or 40%. I don't think that changes the scope or the nature of the mission at a significant level. You know, the honest fact is we can't afford to do a 15 meter, but a six meter class mission is gonna produce transformative levels of knowledge about evolution in nature of planetary systems around less sun-like stars at au scales, irrespective of what the exact eta-sub-Earth that has been measured actually is. And I don't think if someone came out and told me today that eta-sub-Earth was half flooded, was twice as high that the survey would have still recommended a substantially smaller telescope. It's also a six-meter to allow it to do transformative Astrophysics across a broad range of topics. Equally if someone says it's half what we think it is. I don't think that means you don't do the mission because still it's the only way to learn huge amounts about other planetary systems. And it doesn't mean do it 12 meter because we can't afford to do a 12 meter. So, I don't actually think by this point, the uncertainty is going to substantially change the mission architecture compared to all the other uncertainties we have. Still when they stand up in front of Congress and justified eight years from now, they've got to say something about the expectations of what could happen. And then my last remark on again, wearing the hat, I sometimes feel like we get a little too hung up about this uncertainty and emission justification. You know, there exists let's say a factor of two uncertainty and eta-sub-Earth and so you used to be a factor of 10. We had Kepler we've refined that you compare that to dark energy, right? The factor of uncertainty and the non cosmological constant component of dark energy is about 138 orders of magnitude, not a factor of two, and no one stands up and says, "You shouldn't do giant dark energy missions "because you're uncertain about what WPrime is gonna be." Instead they say, let's go measure it by doing a mission. And so, you know holding this things to the bar that you have to promise, it'll be exactly 25 Earth-like planets feels too hard. Instead you design a mission that's robust against these uncertainties, and that will measure interesting numbers no matter what the universe provides to us. - Exactly and the only thing I'll add or actually ask Bruce, I'm trying to remember now, do we include in the final report, a figure that tries to represent the eta Earth uncertainty? I forget the exact context, but in any case, I would just say, suffice it to say that, some reasonable understanding of the current estimated uncertainty in our knowledge of eta Earth was before us, right? - Yeah and that does drive the mission architecture because the yield climbs fairly steeply early on, you know, a three meter class telescope wouldn't have been robust against eta-sub-Earth uncertainties, a six meter is uncertain and that is robust enough that it would have to be a really evil universe for that. It wouldn't get any spectrum or a size planets in habitable zones. And, so the mission I think, is robust at the factor of two level. - Thanks and I think Bruce, you said you referred to the six-meter class telescope would be something to do transformative science across all Astrophysics, right? And so I think that's actually a good segue into this third top ranked question here where it says, you know, Astro 2020, didn't recommend explicitly any of the four mission concepts that NASA supported the development of. So in retrospect, would you recommend that a similar or maybe a larger or smaller effort be devoted to developing mission concepts prior to the next decadal survey? You know, should we go through the same exercise basically in 10 years exactly, as we did this time? - Well, I'll start by saying that. And maybe it's best if I say that, this is just my own view, and this is not divulging anything about internal committee discussions, but just my own view is that reading as an individual astronomer reading through those for concept design reports was really, really helpful for getting a sense of the range of possibilities, for these different contexts. So I don't know that that really answers the question, but I guess I feel like having those concepts with some specificity to them so that you can get a sense of the range of possibilities and different kinds of configurations and things it yields is helpful. - Yeah, I would second that, I think it's just critical. I think, like I said before, even for missions that didn't get selected, knowing what existed in parameter space was part of building the balanced scientific portfolio and knowing in a way that was realistic so that you're not weighing PowerPoint view graphs against detailed mission studies, you need to weigh detailed mission studies against each other. But recognizing that they should be thought of as pieces in a complicated mission phase space that we've evaluated the mission science cost function at two or three points in a huge three-dimensional space. And we ended up interpolated between those spots a little bit or suggesting interpolation between them, but that isn't meant to undermine the details and the technical details that went into all those studies from coronagraphs to detectors are an important part of being able to stand up and say that we can do this. And the quantitative science studies that happened in them that show these measurements will enable the science. So, yeah, I mean those are absolutely should happen. I would maybe say even on a larger scale, but it's hard to get, there's not that many people in the community so. - Thanks for that. I see there are some more great questions in the tool, but there are other topics we want to try to cover. So I think in the interest of time, I'm going to actually pivot to Josh Pepper to take over as moderator. - Awesome, thanks, Knicole. So I think we heard several questions dealing with Flagships and large telescope missions. I wanted to adjust the view a little bit to talk about probes and mid-scale initiatives. Now these cover a wide range of topics. There's the two probe type missions that were suggested by the decadal, which interestingly, I think while they could tangentially address certain topics within exoplanets, they tend not to be primarily exoplanet focused, but one of the other key mid-scale initiatives that was proposed as the Time Domain Program for NASA to establish, which I think is an extremely important one that covers a lot of areas. And what I'd like to ask the committee is, or our guests here is Time-Domain Astronomy has very often been conflated with Multi-Messenger Astrophysics through lots of casual discussions in the community. And while they are certainly deeply interrelated, they are not the same thing. And there's a lot of Time Domain science that still needs to be done outside of the Flagship missions to understand exoplanets. So I was wondering when we think about a Time Domain Program, what would you guys tend to suggest is the way that the community should think about it in terms of its relevance to exoplanets? And that's to whoever would like to pick that up? - Well, so maybe first I'll offer a very general response to the Time Domain area, and then maybe just one thought specific to exoplanets. So the general thought is, I mean I think what we try to do in the report right? Was to sort of elevate and we've used the term Time Domain Astrophysics in the field now, in a number of different contexts, and it's kind of become a standard phrase to use. I think, we're really kind of trying to elevate it as something that needs to become an intentional activity, right? I mean, we even recommend the creation of sort of a PAN or sort of inter-agency kind of coordinating group or in our groups within the agencies that would look within each agency, maybe even talk to one another. So that Time Domain Astrophysics is something that is being thought about intentionally across these different assets and platforms and scales and timelines, right? In an ideal world, we would have a kind of panchromatic swarm of instrument and detector capabilities on the ground and in space so that you could capture some event or some of some phenomenon on a variety of timescales, if not in real time, rapidly follow up with them across a number of different wavelengths and modalities, right? So you know kind of I think the vision for the Time Domain recommendations is to begin thinking about okay we can't populate all of panchromatic and timescale and ground and space, you know parameter space, but as we're deploying mid-scale missions and instruments in space and on the ground, as we're thinking about the different kinds of capabilities that different platforms are capable of, instead of only thinking about sort of the primary scientific mission of a thing, can we simultaneously be thinking about how this new mission or capability can fit with the larger network or constellation or suite of assets to really enable something like a panchromatic multi-timescale, multi-platform Time Domain system, right? So that's sort of the general comment in terms of exoplanet science specifically, I think we talk in the report, or I think it's certainly in one of the panel reports, ultra-precise light curves is now a kind of commodity, you know has become a kind of staple of what we now kind of expect and need to have as part of a large-scale ongoing Exoplanet Program, right? And so I think that is a specific kind of Time Domain capability that has become right central to exoplanet science. And so I would imagine, I would hope that part of what will continue to be in our collective thinking, especially on the smaller mid-scale kind of scale of things, is how do we sustain that kind of industrial scale ultra-precise light curve kind of capability really important? - I guess the other things I would add would be the primary recommendation is to establish a committee. So committees reproduce themselves and create more committees. And that's what the Astro 2020 did that will make recommendations. And there absolutely should be exoplanets/stellar activity people in the room on that committee to be part of that dialogue. But it is to be completely honest, the language in the report we should say, does it emphasize the transient phenomenon more than sustained Time Domain monitoring, like transit detection and stuff like that. So I think the recommendation is pretty clear. It's more about what capabilities do we need to do multi-wavelength follow-up at transient, which could include some AMSTAR burning off all of the life in its immediate habitable zone. But that's the area in which the gap was identified are the risks of failures of the missions that do this going forward. And so as exoplanet, people should be in the room to say, these wavelengths in these timescale capabilities are needed. It's the recommendation certainly isn't all about chasing LEGO events, but it is much more about transience I think yeah. You know Multi-Messenger, I agree is maybe an overused phrase, transient might be the phrase that you want to be thinking about in this context. - Okay, great thank you guys very much. And it sounds like this might be something that a cross-PAG discussion should take place to make sure that exoplanets are not left out of transient Time Domain type discussions. Okay, in the interest of time, I think I should turn this over to Michael Bottom. Who will be discussing the next topic. - Thank you, Josh. So I was tasked with asking some questions about SmallSats and CubeSats. And I actually so just to summarize briefly, the report was generally endorsing of the possibilities that these platforms offered, but also somewhat agnostic as to whether SmallSats offered a compelling, like long-term Astrophysics capability. Now the things that were highlighted was the potential for the science return, the tech development, the ability to train the next generation of instrumentalists and scientists and particularly broadening participation. But I guess one question I really had was what role do the committee see for SmallSats and CubeSats to play in this sort of 10 year pre-launch tech development phase for these major Flagship missions that was highlighted by the Astro 2020 report? - I think this is a complicated one to talk beyond what's in the report I think, although it also note that there's some good discussion in the appendices, which are not binding on NASA, but provide context for people thinking about these things. I guess putting on my hat again as a personal astronomer, I think it is fair to say there's some tension in the way NASA has structured the SmallSat Programs between science and technology development and willingness to accept risks that the call, the Explorer MO calls do not include technology development as a rationale for picking a move and encourage relatively conservative risk postures. I think decisions about whether, for example technologies, and so they don't necessarily provide a way in which you can weigh a mission that says, I'm gonna go measure X-ray spectra of 372 quasar versus I'm gonna prototype whether MKIDs work in space. The current structure says who cares about MKIDs that care about doing science. And so you pick the light groups of 372 quasars or whatever I'm making these SmallSat concepts up obviously. If there are technologies that can only be prototyped and missions as part of addressing the TRL gaps, then presumably the flag that would be more the responsibility of the Flagship Mission Maturation Programs to do it. Lisa didn't make Lisa Pathfinder compete against Explorer missions. It just was recognized that it had to happen and so it happens. So, again I should say I'm doing all this wearing the hat, making competed missions both do science and advanced technology doesn't feel like necessarily, it's gonna be a successful model to me going forward. And then, the design studies that were put into it did not identify the needs for doing space prototypes, doing flight prototypes. If you can do amazing science by flying a small coronagraph, that's a good reason to fly a small chronograph. Yeah. The CubeSat scale keeps that are below our resolution. And so if you advanced TRLs with CubeSat, then that sounds great. - And I guess maybe I'll just follow on, there's a question posted in the question tool, which kind of is more broad than the one I asked, but I'll just ask it since it's broadly related. It's at the Astro 2020 panel noted that, "The panel "also observes that NASA could consider "pursuing different design approaches in the future "for very large aperture telescopes, "because the Astrophysics budget may not increase "as rapidly as telescope costs." That's a quote. And then the question I asked with very few entry points and practically negligible funding and low TRLs over the past decade, the mission concept that could be considered for the Astro 2020 or incremental rather than innovative or revolutionary at a time when the commercial space industry is undergoing an unprecedented transformation and how will NASA Technology Development Programs in the next year changed to support and nurture low and intermediate TRL technologies to enable affordable very large aperture telescopes? - And there was a general recommendation to enhance funding at low TRLs and at mid-TRLs to enhance APRA and SAT funding, which creates the opportunity for new technology approaches, figuring out how to integrate the commercial space. You know, as we all know, there's a bunch of reasons why the revolutionary models in commercial space don't necessarily apply to scientific just to Astrophysics missions, but that there is a recommendation that NASA should be doing enough, should be doing more on early technology. And that that process presumably would identify opportunities for more transformational stuff going forward. - Okay, thank you. - I might just add, again just taking a very, very broad view of things. You know we were very intentional obviously because we did it in incorporating the notion of pathways into the very title of the report, right? And I think there's a hope that the agencies will seize the opportunity at all these levels of sort of granularity of activity and programmatic funding and so on. To be seeing an opportunity there's a call here to be thinking what's on the horizon that we're trying to accomplish. And then they're very various levels of granularity of activities that need to be supported in order to get there, right? To lay the planks of various widths on the bridge that you're trying to cross, right? I realize I'm being very kind of abstract and metaphorical in my language here, but I think it's another way of saying that, there's a certain level of resolution as Bruce keeps saying that we just weren't going to speak to in the decadal, but really and truly the idea of, you know, we have these scientific questions that we really want to get to as a community. And so now as a community and the agencies, need to put in place the various levels of granular, high resolution activities that need to happen in order to make that pathway real. I'm not trying to be poetic. I mean, I'm really trying to you know I think kind of share the sense of optimism and kind of empowerment, right? That this kind of capacious way of viewing what we're trying to accomplish I think, you know enables for answering a lot of these just more granular questions. - I should have used the word inspiring instead of attendant as a statement of admiration. - No, thank you. Thank you to both well said. I think maybe I'll turn it over to Ofer Cohen for his section as well. Thank you. - And thank you, Mike. So I'm gonna discuss the broader relation of this survey or report to other communities. The report made it very explicit and clear that reaching out to other communities is crucial especially in the context of the exoplanet research. You know, we essentially stated that exoplanets characterization must have come contribution from earth science, Heliophysics and planetary science, as well as to Astrophysics. It makes explicit relation in the context of star plant interaction and the impact of the space environment and the of the hosting star on the exoplanet atmospheres. And that's essentially the Heliophysics domain. And also it makes an explicit statement of the importance of solar physics as our natural laboratory to investigate complicated non-linear plasma physics system that appears all over the universe. The survey did not really provide too many statements about what or recommendations about how we can actually reach out to the other communities. We know that NASA has spend a lot of effort to create some venues for these collaborations and interdisciplinary contributions in the form of either workshops or funding programs, such as the XRP, which has a contribution from all four divisions. Can you elaborate about some discussions that may have been among the committee of how the Astrophysics community can reach out to the other disciplines and a more formal and establish ways to do that? - Well, coming back to something that we talked about a few minutes ago, I mean one area where I think we're pretty explicit in the report about wanting to see some real coordination and intentional thinking about capabilities is in the Time Domain context. And I'm trying to not answer the question as you posed it, because you were asking about sort of discussions within the committee, but rather kind of think about things that we did explicitly say in the report that speak to cross divisional, or kind of cross cutting capabilities, Bruce. - Yeah I mean, I don't think it probably is fair to say that there's not things in there about specific mechanisms to enable this cross divisional collaboration. And that's partially because it's hard. We can't write a recommendation to NASA Earth Sciences and expect them to particularly follow it. And so it's going to be internal to NASA to think about how to do these things or to reports that are more, cross-disciplinary like the pair of astrobiology and yeah. The astrobiology report that was kind of a sister report to the Exoplanet Science Strategy. So yeah, I think there's not identification of mechanisms and it's something the community has to work out. And I have confidence in the community's ability to work it out. There are good examples like XRP or the ways in which the NExSS Institutes and the Astrobiology Institutes have been somewhat cross-disciplinary so it feels like we're doing okay at this. We could do better. You know the two that were more complicated, maybe don't bear on this call as much. There was a recognition that Heliophysics and solar stuff is in this awkward gap where there's a separate Heliophysics report for everything except to NSF ground-based telescopes of which one of the two largest NSF initiatives of the past decade was a ground-based solar telescope. And so figuring out how to cope with Heliophysics was highlighted as a structural problem without a solution being prevented. And then DOE is also very complicated to interact with it. Doesn't bear on exoplanets at all, but DOE is not a consumer really of the decadal survey. It has its own recommendation process and how that syncs now that DOE is actually one of the biggest players in ground-based optical astronomy. And doesn't listen to the decadal survey that feels like a complicated issue, but doesn't bear on exoplanets too much. Excuse me I said that, that statement about that model, the decadal survey I was wearing the hat. That's not a thing that the survey says, so yeah, I think we do have to find, but yeah we didn't really have... We did not present clear recommendations for how to improve things, but I think we started doing okay. - Okay and I'm gonna pass the microphone to Michael again. - Well, we're all of us can chime in here. We're trying to address as many of the questions that are in the Q and A as possible. Some of them have been merged or covered by versions of the questions asked here, let me just follow up what Ofer was discussing as you presumably tried to write a report that would have maximum impact and be most useful. So now as the advocacy part, and I presume we want to engage the community again, to support the process and to be proactive in making sure we get the most out of the recommendations that we have. Do you wanna share any thoughts about that part of the process? - Yeah and yeah, that's the crucial step going forward. I think it's really good that the community seems to have come together and that people can wonder about individual details that we did or didn't do, but there doesn't seem to be a massive backlash, which is, an insecure Canadian. So I worry people won't like me. So I was expecting massive backlashes and I'm glad that didn't happen. You know, we have to stay united and speak with a single voice. There are certainly cautionary tales in the past, like the struggle between the different, ground-based extremely large telescopes, that pretty much torpedoed and NSF role in ground-based extremely large telescopes. We don't want that to happen again. We want this new Flagship mission to be seen as all of our missions that we're all coming together and it feels like we are becoming the natural community that will support that. You know, support is going to evolve, participating in the committees that are gonna do the definition of the missions, continuing to do the work. It will involve lobbying at the Congress level. It will involve speaking with a unified voice to other astronomers to make sure that, that what we wanna have go forward. It feels like we're doing it, but we're gonna have to work really hard to keep doing it. And I'm kind of looking forward to that, to being part of that process and to being a voice, to keep doing these, and also not just on the Flagship missions, but on the state of their profession stuff. That's let me say that explicitly, it's really easy for the small recommendations to get lost in the dialogue about great glorious Flagship telescopes. And that really shouldn't happen. I think we need to stay advocates for the funding, for opportunities across the whole spectrum that are contained in a state of the profession chapter of the report and advocates for the funding for fundamental research support. That that's an NSF thing more than an asset thing, but it's really easy to imagine the recommendations for increases in foundational grants to get lost in NSF, among the dialogue about giant telescopes. And so as all of us are being advocates, let's remember to advocate for every aspect of their report for this stuff on different scales, and really remember to be advocates for the stuff about improving the profession. - I think that's very well said. I don't have anything to add to that, I think that's great. Maybe I'll just say look at you know, when you're thinking about advocacy, look at figure one and two, in the report, right? You know, one of the, I forget which one is which, but one of them is the one that just kind of represents in this sort of timeline kind of colorful way. You know, I mean, I still look at that figure all the time to just kind of remind myself where are we really headed? And even though some of those seem stretch beyond my human timeline, that's really quite, edifying and uplifting and exciting to think that we are really trying to undertake such grand exciting and ambitious questions. And the other one of those two figures is sort of the pyramid figure that reminds us, that supporting the community, the scientists whose creativity and labor make it all possible or the foundation upon which it all rests. - Thank you, Bruce. And Keivan, I'd like to ask if any of our colleagues from headquarters would like to comment or speak to any of the issues that have come up so far in this conversation, Doug or Hannah, would you like to say something? - I guess I'll just chime in to say that a lot of the questions about, what will NASA's response to X statement and the decadal survey will be, I think we are gonna be answered in the next couple of hours when Paul gives his town hall. So please stay tuned to that. Please tune in. And of course, I'm gonna be giving a talk tomorrow at the beginning of tomorrow session of ExoPAG and can feel free to if time permitting, of course you can ask questions then if there are any remaining questions, but I think a lot of the discussion questions that have come up will be addressed by the time of town hall. - Doug, do you have anything you wanna add to that? If Doug is on, he might've been called away for a moment, we'll come back to him and thank you for sharing that Hannah of course, we look forward to Paul's address in a few minutes. This is also the reason why some of the questions that were posed were not specifically asked because they really related directly to the NASA's response in funding to specific elements of the survey. So we'll wait to hear from Paul. And as you mentioned, thanks for advertising your talk. We'll open our session tomorrow with some of the important Exoplanet Exploration Program talks and Hannah will present the view from HQ as a deputy program scientist. So please do join us tomorrow. We felt this was a reasonable way to proceed to talk about the report and the kind of aspirational recommendations. And then Paul will give us the first response from the NASA Astrophysics Division. And then tomorrow we will meet again and have the opportunity to digest some of what we heard and ask clarifying questions of Hannah and others, and then move into our business meeting where more general conversations can occur. I'd like to invite anyone else on the moderators or anyone else on the EC or other ones who want to resurrect one of the questions we have not gotten to sufficiently, or to ask a new question that hasn't yet come up. - If it's all right to chime in here. So I was talking about the mid-scale initiatives and probes. There has been a question of RACE, on the Q and A session that I think I've heard asked in other venues, which is why was that the designs of the proposed probes are the X-ray infrared as opposed to leaving it open? I'm sure there are good answers to that, but I think it will be useful to hear that just because it is something that I've heard elsewhere. - Designs or wavelengths? - Presumably the wavelength machines. - Yeah, I mean Bruce helped me with this too, but I think we wanted to... And I think you'll see, kind of a similar spirit of guidance. If you look at the recommendations that we may pertain to mid-scale activities on the ground, where across the board, I think we wanted to provide some guidance rather than just saying, "Look, it's important "to do these sort of mid-scale things." And so keep supporting mid-scale things. We wanted to also say, here are some specific strategic opportunities where it seems like you might want to start focusing investments in these mid to kind of large mid-scale opportunities, just as one specific example, the idea of doing something at this scale and the X-ray domain that could come to fruition on a timescale where we may be looking at Chandra, sun setting or retiring at the same time, ESA is you know it has plans for Athena, right? So that's just one example where it seems like there's a specific opportunity in a wavelength domain where we may be faced with the loss of certain capability on the one hand and the opportunity for complementarity at the same time. So that's sort of how we were thinking about these things. - Yeah, same, same thing in the infrared plus technology advances that there's been enough progress in technology that a billion dollar scale mission could be still pretty transformative, in the far-infrared with large format detectors and colder telescope than Herschel, et cetera. And that one, I would note does bear on exoplanet. So if billion dollar infrared can't do everything, you can't have a mission that does the high ridge of universe and traces HD through protoplanetary discs, but a billion dollar mission that emphasizes high spectral resolution could be a transformative exoplanet formation mission. But we didn't dictate that the question of whether the mission is High-Redshift Universe or High Resolution Spectroscopy is gonna be left to the architecture, evolutions and determinations. So yeah, I think it was an attempt not to be true prescript shift, to identify there's a couple of really clear opportunities where the technology and the science gaps and the science needs came together. - Great, I think that's a great summary of answer. Thank you-- - And by the way, hopefully people saw the SMD announcement of opportunity for the first round of probe concept space, came out. - Indeed. - It looks like that's at a billion instead of a billion and a half that we recognize that will be interesting, but that's, you know, again don't take our numbers to significant figures so. - Well again, Hannah or Doug or Keivan or Bruce or any member of our moderators or others who feel that the responses to the questions posed were inadequate or wanted to share one more thought this is a final opportunity to do so. If anybody wants to stand up and raise their hand, even to ask a question, I know I've discouraged that up to now. We felt that this Q and A chat channel would be a way to aggregate as many people's interest as possible to facilitate a discussion here, but we wanna make sure everybody feels heard. - I might just point out that there are already some relevant National Academy's Report activities that will connect with some of the themes in the Astro for 2020 decadal. I don't remember if I saw this in the chat or in the slack or somewhere. I saw a question along the lines of sort of the future of NASA mission leadership. I'm sorry, I'm forgetting exactly what the question was or how it was posed, but it was along those lines. And so it reminds me to point out that there is, as we speak an active Consensus Report Committee that is specifically looking at ways in which NASA can better support the broad development of the future leadership specifically for completed NASA missions. So be on the lookout for that report, I would say within the next few months. - Yeah, there's some good discussion about that buried in one of the appendices of the main report, but there was a decision not to tread on this later committee with detailed recommendations but to support it. And I think we all know, and it is acknowledged in the report that the diversity of PIs for Explorer-class missions is not what we would like it to be. There are a number of reasons for that. And hopefully this other committee will address them. If I put my hat on, I have personal opinions about that that the explorers are stunning, but we could do better in terms of making sure there's a range of people across demographics, across the institutions who do them. Yeah, it's an ongoing process. - Indeed thanks for reminding us of that and pointing that out. And I guess now it would be a good opportunity to, before we close to thank Bruce and Keivan, maybe we can clap virtually or unmute and clap, actually clap. Thank you for taking time and sharing your thoughts with us today. We really appreciate it. Oh, there's a raised, oh, no, there isn't nevermind. And with that, I think we're prepared to take a break for 15 minutes and please don't forget, Paul Hertz will be giving his NASA town hall address in about 15 minutes from now 2:45 Eastern standard time. And so please listen in to hear the first response from the NASA Astrophysics division to the Astro 2020 report. And let's say hi to Bruce is up there and thank you both. - Thank you to you so much. This really is a community driven process. And so seeing the community turnout is really, it's really great, really great to see that. Thank you all. - Thank you all for the chance to talk to you. - And I'll thank just again, our back behind the scenes people, Jennifer Gregory, and the huge team of people who've been making this happen. It was really a heroic effort this week to make this work. So thanks very much to them for making this happen. And indeed, we'll see you all tomorrow at 9:00 AM Eastern time if I'm not mistaken, Jennifer, no 12:00 PM Eastern time, 9:00 AM Pacific time. Excuse me. - That's correct. - All right, bye now everyone. - [Jennifer] See you then take care.