Meeting Minutes - OST STDT Bi-Weekly Telecon - October 20, 2017

Goddard Study Office Status – Ruth Carter – See Carter’s PowerPoint slides

  • Have received instrument map & list; we need instrument costs to make it complete
  • Working with cost team branch at GSFC. This takes some time, because some items are not there yet, so we are making estimates & judgments at this time
  • Have completed Concept 1 design with all telescope, instruments, and instrument accommodation module
  • There are things we have to work on more to demonstrate feasibility
  • Have to identify what we are going to do in each area to segway to Concept 2
  • HQ has delayed schedule, but we are not going to delay our schedule so we can finish ASAP and move on to Concept 2 to spend as much time as possible on Concept 2
  • Propose finish writing it up and then have November 17 review
    • October 31: Draft due
    • November 1 – November 7: Integrate all sections
    • November 9: Final draft distributed to reviewers
  • Review will be done section by section
  • New delivery date for HQ is March for interim report, later for final
    • Meixner: HQ will take reports earlier, however
    • Still intending to deliver interim report in December
  • Will update management plan and post for everyone
  • Interim Report Review will be on November 17 at NASA GSFC, Building 34, Room W305
  • Reviewers are: Susan Breon (GSFC), John Mather (GSFC), George Rieke (U. of Arizona), Mike Werner (JPL), Jean Turner (UCLA), Phil Stahal (MSFC), Lee Feinberg (GSFC), Tupper Hyde (GSFC), Dave Everett (GSFC), Jeff Bolognese (GSFC), Patrick Thompson (GSFC)
  • Also plan to present idea of what we might be doing in Concept 2
  • If anyone has suggestion about review, send message to Ruth Carter or management team
  • Carter received Sample 2010 Decadal Questionnaire for CATE Analysis; she broke down by Science and Enabling Technology
    • All of these bullets must be addressed in final report
  • Dave Leisawitz: Bullets shown by Carter are high-level highlights of very detailed questionnaire

Mission Concept 2 – Margaret Meixner

  • Recap on telescope diameter exercise (Meixner presented table of results)
    • Sent final results for telescope aperture to STDT
    • Had all cases except for high-z
    • Alex Pope: We generally found that 5-meter still had compelling science; 3.5-meter had less-than-compelling science
      1. For 1500 hours of exposure time, could do it with 5-meter, could not with 3.5-meter
      2. For first dust, need redshifts of 8-9; won’t have with 3.5-meter, 5-meter might just be able to do it, 8-meter could definitely do it
    • Klaus Pontoppidan: with 3.5-meter only barely getting down to stellar-mass stars at distance of Orion (water content)
    • Matt Bradford: 3.5-meter should have some science left with disks
    • Meixner: Kevin didn’t think that 3.5-meter could do the science they desire
    • Question for Kevin: Can methane be detected with 5-meter? (methane not included in table)
    • Meixner: Of course everyone would like the larger aperture, but when you look at table, science also might not be transformative with 3.5-meter
    • Leisawitz: When we’re talking about aperture size, we’re talking about light-collecting size, not shape of mirror; shape could affect some science
      1. Question: Are there any objections to non-round mirror?
        1. Might add another layer of analysis for data reduction
        2. Might possibly affect rotation
        3. Kate Su: shape should not affect their science; Leisawitz: there could be advantage to have different angles; Su: perhaps but bottom line is we want high resolution and stable PSF
      2. John Mather: Went through this discussion with JWST; some needed a round image
      3. Dave Leisawitz: If we consider a non-round aperture, should check with everyone to assess affects
      4. Tom Roellig: May be considering non-round aperture for Concept 2, so should get feedback sooner than later on other shapes
    • Meixner: We lose our top 2 or 3 science priorities if we go with 3.5-meter; could do some others but they are much more transformative with the 5-meter
      1. Suggest reviewers look at 5-meter and assess cost of that
    • Results on instrument prioritization exercise (Meixner presented table)
      • Only group have not heard back from is small bodies (might be at DPS this week)
      • On the first two cases, prioritization would place FIP higher than HERO
      • Alex Pope: Cannot really use HERO, can use FIP
      • report from Kevin: 3.5-meter not feasible for transiting exoplanet biosignatures
      • Pontoppidan: HERO has higher priority than FIP for water content of disks
      • Joaquin has MRSS, MISC, FIP, HERO, HRS ranking for 5-meter
      • Karin: tentatively, need more time to discuss with working group; have a case that depends on FIP, another case that depends on HERO
        1. Path of Water uses HERO
        2. Meixner: a good discussion would be could you use both?
      • Kate: ranking is MRSS, MISC, FIP, HERO, HRS (FIP higher than HERO) for Frequency of Kuiper Belt Analogues
        1. reducing the field of view does not affect us
      • Meixner: First question was do you agree with this prioritization; can change prioritization for smaller field of view
      • Early Universe: Cutting the field of view in half cuts the science in half
      • Karin: Field of view should not affect Galactic science
      • Goal today not to resolve everything, but to air some issues
      • Carter: Once instruments are prioritized, some need to be smaller (particularly MRSS)
      • Matt Bradford: What we’ve heard is both mass and power are considerations, but mass is only one associated with cost
      • Carter: 4,000 kg associated with instruments & instrument module
      • Leisawitz: Need to follow up with Matt with the point he’s making; figure out whether we can make that happen with much tighter mass budget
        1. Carter: Suggest having telecon with Matt and his team

Interim Report Writing – Asantha Cooray

  • Asantha not on telecon
  • Leisawitz noted:
    1. Email from Tom Roellig said to prioritize science prioritization scheme so we’re using the same numbers
    2. On Sept. 12, Meixner distributed writing style guidelines to STDT; reminded everyone to use style guidelines

AAS Brochure – Narayan, Carter

  • Narayan had to leave
  • Cara Battersby: Still sorting it out; want to include FAQ in brochure
  • Carter: Cannot have a pop-up; for the punch-out model, can assemble quickly
  • Battersby: need to change wording to make it fit and more updated
  • Carter suggested having a telecon after first draft
  • Leisawitz: Looking for one line for brochure about what OST will do
  • Meixner: “Seeing beyond the light” doesn’t do anything, doesn’t know what it means
    • Leisawitz: Need other ideas

Other notes

  • Tom Roellig: Talking to Asantha yesterday, cost for JWST has gone up to 3.9 billion and asked to pull back to 3.2 billion; might be a good target for us
  • Anel Flores: Colleagues might have to go to Class A type mission as well