Sunday, July 21, 2019

A proposal for our next "giant leap" beyond the moon: the Solar System Explorer

As we celebrated the 50th anniversary of the Apollo 11 moon landing this weekend, the Chronicle asked "What’s our next ‘giant leap’ beyond the moon?"  That reminded me of an old unpublished op-ed I submitted way back in 2003, but I think it still holds up after all these years. See what you think and let me know in the comments.

A New Mission for NASA

“In Search of a Mission” reads the bold Sunday Chronicle headline, kicking off a six-part in-depth series on NASA after the Columbia tragedy.  In search of a mission, indeed.  The Columbia disaster has surfaced many reservations about NASA and its $15 billion dollar annual budget, especially about the limited scientific contributions of the manned shuttle and space station programs.  NASA seems to have lost its way, and a growing chorus of voices is calling for a renewed vision and reinvigorated leadership.

Some of the more extreme voices – focused purely on maximizing “bang for the buck” science – are calling for a severe curtailing or even elimination of the manned programs in favor of more unmanned robotic missions like the very successful Mars Rover.  But no matter how much the economics make sense, most people agree that there is something important and magical about manned exploration of space – a shared passion for simple human exploration that goes beyond the pure science.  NASA needs an inspiring vision that recognizes the importance of manned exploration, the value of good science, and the realities of budget constraints.

I believe that long-term vision – that big, audacious goal to motivate the tens of thousands of NASA employees, contractors, and scientists – should be no less than the eventual construction of a Solar System Explorer: a manned ship designed to go on long-range missions to Mars and the moons of Jupiter and beyond.  A flexible, modular ship that could perform base-building freight missions to the Moon in addition to its long-range exploration missions – designed to return to Earth orbit again and again and again for refitting and upgrades for the next mission.  This would be a ship designed to be built-in orbit and never touch the surface of a planet (although it would certainly carry landing modules).  The Solar System Explorer would bring a level of excitement back to the space program not seen since the 1960’s race to the Moon.

Unfortunately, such a ship is well beyond any budget reality that exists today.  This is where a short to mid-term vision for NASA comes in: they need to create a “Moore’s Law of Space Travel.”  Moore’s Law is named after Gordon Moore, who postulated in 1965 that the price/performance of semiconductor chips would double roughly every 18 months – a prediction that has held up remarkably well ever since to be the dominant driver of our computer and Internet revolutions.  Just as Intel has helped drive those improvements through sustained R&D investments, NASA should drive improvements in space travel economics through innovative R&D investments in propulsion and other systems.  Just as the NIH gives out grants to test innovative approaches to attacking our most intractable diseases, NASA should administer grants to test a wide range of possible approaches to reducing the costs of space travel.  Doubling every 18 months is a bit unrealistic, but even smaller gains can compound over time until the Explorer is financially feasible.

This approach allows NASA to “think big” – so critical to morale and public support – while staying grounded in economic realities: an inspirational mission balanced between head and heart to launch the space program to new heights in the 21st century.



At 12:35 AM, July 22, 2019, Blogger George Rogers said...

Moore's law was an observation that after a few years of designing chips that you can put twice the number of transistors per mm^3 of chip every 18 months.
It was not a predictive law at first.
Also government is not good at solving undefined problems so this will not work.

What made Apollo so successful was that it was a defined, ambitious but still achievable with technologies that could be envisioned top down from that goal.

At 9:28 AM, July 22, 2019, Blogger Tory Gattis said...

That's a good description of Apollo - a brute force, "throw all the resources at it" approach.

For the SSE, I think NASA would have to put together what they think it would look like and cost, then identify the technologies needed to make it dramatically cheaper. One of the simplist is "who can massively reduce the cost per pound to get stuff into space?", which is what companies like Space X are working on.

Another thing they could do is "open source" a lot of the design to universities and others, who could use student projects to design different parts and estimate what it would cost to build. Since it's open source, new efforts can always try to improve on the old. And automation is good enough these days we should be able to test anything we build unmanned first, dramatically improving safety.

At 1:57 AM, July 24, 2019, Blogger George McKee said...

There's this small problem, though, with maintaining human health during long-duration spaceflight. We know, thanks to the heroic endurance of Scott Kelly and other astronauts and cosmonauts, that staying in zero-g for a year causes serious, maybe irreparable harm to many physiological systems. We don't know if the problems get continually worse forever no matter how long the duration of zero-g lasts, or if there's some asymptotic level of adaptation that can be achieved.

We don't know if fractional gravity might help. Maybe the 1/6 g of the moon is enough to mitigate those problems, maybe the 40% g of Mars is enough, maybe it takes a full earth gravity equivalent. Going to the moon and staying there for awhile is a critical first step.

Not to mention the radiation hazards outside of earth's protective magnetic field. There may be creative solutions to space vehicle design that deal with this, but they haven't been published in popular media. The proposed spacecrafts just assume that living for years in the radiation field of an unshielded nuclear reactor (i.e. the sun) with dosage rates significantly above what's allowed for workers in fission powerplants, is something that won't cause any trouble. Building radiation resistant computers and robots is well understood, we don't have that option with people.

A series of grand tours of the solar system would be a grand adventure, but not if they include death sentences or long term disabilities.

At 9:28 AM, July 24, 2019, Blogger Tory Gattis said...

I agree those are big problems probably requiring artificial gravity (i.e. spinning) and probably using water tanks for shielding. But that's the role for the R&D/Moore's law piece.


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