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Posted by: Drkskywxlt Mar 8 2011, 01:22 PM

The report was unveiled to the community last night at LPSC by Steve Squyres. The full report is on the National Research Council's website.

The recommendations:

1. Increase R+A funding by 5% above the FY11 budget and then by 1.5% above inflation per year for each year thereafter
2. Maintain a technology development fund at 6-8% of the Planetary Science division budget (~$100M). This includes tech development for Mars Sample Return (particularly the Ascent Vehicle).
3. Continue Discovery program at current funding plus inflation adjustments and keep a schedule of no more than 24 months between AOs and selections
4. Mars Trace Gas Orbiter as long as the division of work with ESA is preserved
5. Increase New Frontiers cost cap to $1B without (!) the launch vehicle. Select NF-4 and NF-5 in 2013-22. NF-4 concepts: Comet Surface Sample Return, Lunar South Pole-Aitken Basin Sample Return, Saturn probe, Trojan Tour and Rendezvous, Venus In-situ Explorer. NF-5 concepts: any unselected NF-4 concepts, Io Observer, Lunar Geophysical Network.
6. Begin NASA/ESA Mars Sample Return by launching a DESCOPED MAX-C rover in 2018. This is the only flagship recommended for start in this decade. This mission MUST fit under a $2.5B cost cap (FY15 dollars). If not, the Survey recommends it be delayed or cancelled. There is no Plan-B for Mars exploration if MAX-C can't be flown. The cost assessment for this mission came in around $3.5B. Steve Squyres said the big reason this mission is so expensive is due to risk and costs associated with landing 2 landers (MAX-C and ExoMars) with one EDL system. He hinted at combining the rovers into 1 rover.
7. A dramatically DESCOPED Jupiter Europa Orbiter. Cost estimate for this mission came in at $4.7B. That was it's death sentence. It scored comparably with the Mars Sample Return for science return per dollar. This also needs to fit under about $2.5B. Recommend it switch to ASRGs for power production immediately.
8. Uranus Orbiter with probes. Uranus was chosen over Neptune primarily for trajectory reasons. Steve Squyres suggested that if this mission waits until next decade, Neptune would appear very attractive as well.
9. Either an Enceladus Orbiter or a Venus Climate Mission as the 4th priority flagship.

Other comments:
1. Technology development priorities: Titan Saturn System Mission, Neptune Orbiter (aerocapture), Mars Sample Return lander and orbiter.
2. If there is less funding provided than their estimates: in priority order, descope/delay flagships, slip NF/Discovery missions only if flagship cuts don't solve the problem, high priority to keep R+A/technology development money safe.

My sense from being there is that the Europa folks were understandably devastated. Sticker shock was pretty severe with these estimates as they were almost 50% higher than many of the numbers tossed around before. I think Titan folks were probably pretty blue as well (although I'm not sure there are many such people at LPSC) since there was no suggestion of a Titan mission anywhere. Based on the cost predictions shown, it seems nearly impossible that some of the Discovery-class Titan concepts would be cost feasible.

Posted by: rlorenz Mar 19 2011, 02:26 PM

A Titan Flagship is called out in the technology development section. But a sentiment I have heard expressed widely
at LPSC* and OPAG, and not just by 'Titan people' is surprise and disappointment at the lack of an opportunity to propose
Titan missions to New Frontiers. But the Decadal survey report acknowledges that there may be a mid-term review - I
could readily imagine that the NF5 mission list might be expanded to include Titan in such a review.

*the LPSC abstract submission website did not have a 'Titan' category, and the 'Fluvial' and 'Aeolian' categories were listed
as 'Mars Fluvial' and 'Mars Aeolian', so some Titan people did not feel welcomed by LPSC and did not submit/attend. I hope
that may change next year.



Let's let the NASA review process be the judge of that, shall we? The Decadal Survey Titan Lake lander study was made
under very conservative assumptions, had a large and expensive payload, and (because the survey studies had a much later launch date) had to use a larger and more expensive launcher than the TiME Discovery proposal.

Posted by: machi Mar 23 2011, 12:23 PM

Titan Aerial Explorer Mission:
http://meetingorganizer.copernicus.org/EGU2011/EGU2011-9531.pdf

I think biggest future problem for outer solar system missions is plutonium availability.

Posted by: hendric Mar 23 2011, 04:30 PM

Listening to the reports of the difficulty of keeping the spent fuel rods cool in Japan, I was wondering if it was possible to use part of a spent fuel rod inside of an RTG of some sort. Probably a million reasons why that is a bad idea, but at least we have thousands of them lying around in pools.

edit:
Nevermind, this answers that question:

http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Criteria

Fuel rods probably put out large amounts of beta/gamma radiation, vs the nice and clean alpha radiation from Pu-238.

Posted by: machi Mar 23 2011, 06:48 PM

For missions to outer Solar system we need radioisotopes with long half-life. So plutonium 238 is obvious choice.
Another possible candidate is americium 241 -
http://www.flightglobal.com/articles/2010/02/15/338369/uk-could-use-plutonium-in-space-nuclear-power-demonstration.html.