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We're on it: https://www.jpl.nasa.gov/missions/europa-clipper/ https://www.jpl.nasa.gov/missions/europa-clipper/ Instruments were selected early this year, and

We're on it: https://www.jpl.nasa.gov/missions/europa-clipper/ https://www.jpl.nasa.gov/missions/europa-clipper/ Instruments were selected early this year, and specific designs and instrument contractors are being chosen.

Sir_Cmpwn 9y ago
I dunno, the vague "2020's" timeline is depressing. If we directed even a fraction of the SLS budget into this it could probably launch in late 2018 or 2019.
- mturmon 9y ago
  No, 2018-2019 is not possible. The instruments are not built yet! There's a limit to what money could do to accelerate. Engineers are doing trade studies literally right now - here's an informal progress report given in October to the Space Studies Board of the National Academies of Science: http://sites.nationalacademies.org/cs/groups/ssbsite/documents/webpage/ssb_183287.pdf http://sites.nationalacademies.org/cs/groups/ssbsite/documen... Hopefully that is reassuring that it's not just an academic exercise! Earliest launch date is listed there as 2022 (page 3). These studies are needed to be sure that agreed-upon science objectives would be met by the instruments. Here is an old Europa STM (science traceability matrix) that lays out the measurement goals (https://solarsystem.nasa.gov/europa/docs/Clipper_Trace_Matrix_V2.2_140609.pdf https://solarsystem.nasa.gov/europa/docs/Clipper_Trace_Matri... - compare around page 16 of the above presentation). The current STM will be much more elaborate. The trade studies and experiments now underway are directed at checking these off or saying why they are not attainable. In particular, note (pg. 14/15) the multi-pronged approach to assessing the moon. One of the pieces is the plumes that are emerging from the surface; how do you locate and sample from one of the plumes? Do you need some on-board software to find them? If so, what sensors does it need?
  - Sir_Cmpwn 9y ago
    Well hey, good luck! I withdraw my concerns (but maintain that SLS sucks).
    - mturmon 9y ago
      All interest in solar system exploration is welcome!
  - ufmace 9y ago
    Neat, thanks for the info! Do you know anything about the possibilities of an orbiter or lander on Europa given the radiation hazards?
    - mturmon 9y ago
      The current nominal trajectory is on pages 6/7 of the first PDF I linked. It appears to be making ~40 near overpasses of the moon in the prime mission, some within 25-50 km of the surface (red lines), which is really quite remarkable considering the distance from Earth, light-time delays, and complexity of the Jovian system. I would conjecture that our gravimetric/orbital model of the Jovian system will be updated during initial orbits so that planning for the overpasses will be refined after arrival. There has been discussion of putting a (hard) lander on the spacecraft, to drop into one of the plumes. Last I heard, there was Congressional interest in the idea, but for technical reasons, AFAIK, it is out-of-scope for Europa Clipper. I think it's in study for a successor mission. It's generally better to not try to do everything with one mission, but to plan a campaign with various contingencies.

Sir_Cmpwn 9y ago

I dunno, the vague "2020's" timeline is depressing. If we directed even a fraction of the SLS budget into this it could probably launch in late 2018 or 2019.

mturmon 9y ago
No, 2018-2019 is not possible. The instruments are not built yet! There's a limit to what money could do to accelerate. Engineers are doing trade studies literally right now - here's an informal progress report given in October to the Space Studies Board of the National Academies of Science: http://sites.nationalacademies.org/cs/groups/ssbsite/documents/webpage/ssb_183287.pdf http://sites.nationalacademies.org/cs/groups/ssbsite/documen... Hopefully that is reassuring that it's not just an academic exercise! Earliest launch date is listed there as 2022 (page 3). These studies are needed to be sure that agreed-upon science objectives would be met by the instruments. Here is an old Europa STM (science traceability matrix) that lays out the measurement goals (https://solarsystem.nasa.gov/europa/docs/Clipper_Trace_Matrix_V2.2_140609.pdf https://solarsystem.nasa.gov/europa/docs/Clipper_Trace_Matri... - compare around page 16 of the above presentation). The current STM will be much more elaborate. The trade studies and experiments now underway are directed at checking these off or saying why they are not attainable. In particular, note (pg. 14/15) the multi-pronged approach to assessing the moon. One of the pieces is the plumes that are emerging from the surface; how do you locate and sample from one of the plumes? Do you need some on-board software to find them? If so, what sensors does it need?
- Sir_Cmpwn 9y ago
  Well hey, good luck! I withdraw my concerns (but maintain that SLS sucks).
  - mturmon 9y ago
    All interest in solar system exploration is welcome!
- ufmace 9y ago
  Neat, thanks for the info! Do you know anything about the possibilities of an orbiter or lander on Europa given the radiation hazards?
  - mturmon 9y ago
    The current nominal trajectory is on pages 6/7 of the first PDF I linked. It appears to be making ~40 near overpasses of the moon in the prime mission, some within 25-50 km of the surface (red lines), which is really quite remarkable considering the distance from Earth, light-time delays, and complexity of the Jovian system. I would conjecture that our gravimetric/orbital model of the Jovian system will be updated during initial orbits so that planning for the overpasses will be refined after arrival. There has been discussion of putting a (hard) lander on the spacecraft, to drop into one of the plumes. Last I heard, there was Congressional interest in the idea, but for technical reasons, AFAIK, it is out-of-scope for Europa Clipper. I think it's in study for a successor mission. It's generally better to not try to do everything with one mission, but to plan a campaign with various contingencies.