Buzz Aldrin Books


Mission to Mars

MY VISION for SPACE EXPLORATION

With Leonard David, National Geographic Books, Multnomah County Central Library, 629.4553 A3658m 2013


Dr. Aldrin wants humans to explore Mars. His approach is more rational than most, beginning with teleoperation of robots from Phobos. The long-term goal is permanent and self-sustaining human settlements (p181). Given that it took 4 billion years for evolution to produce our "better of most possible worlds", and a vast interconnected global economy to send a tiny amount of hardware into space (so far), it is difficult to imagine how a second survivable world can be created on inhospitable Mars without magic.

His timeline for the buildup to this starts before the book was written, after a meeting with President Obama in 2010. Obama's speech saying "by 2025, we expect new spacecraft designed for long journeys ...". In 2017, as I write this, politician's claims remain grandiose but the progress tiny. Such developments require far more time than a US presidential administration, and every new administration arrives with new speeches and new campaign contributors to fund. Reset the clock, choose different goals, make bigger claims than predecessors, spend more, accomplish little.

Aldrin is correct that a second manned race to the Moon is a waste of time and money. But the Moon is valuable for many kinds of research, and economic development. Throughout history, exploration was soon followed by economic exploitation. If we skip the exploitation part, what justifies the continuing expenditure? The great explorations of the past were driven by profit and power.

On page 20, Aldrin calls for a reusable booster. SpaceX reused a booster early in 2017, and we will find out how that actually affects the bottom line when Elon Musk runs out of rich folks willing to invest without dividends. Upper stage reusability is difficult, as even Musk attempts to tell the public. Musk claims he will go to Mars in his Dragon capsule, but even Aldrin's cyclers may be too cramped for this very long journey.

Aldrin hopes for cyclers in 2029, a Phobos visit in 2033 (last color plate) ... starting with a Constellation replacement in 2010. Didn't happen, restart the clock 7 years later. If we have any sort of orbital crew vehicle by the end of 2017, and the cadence of this illustration holds, we might reach the Phobos in 2040, and travel to the surface and back years later, when Musk is in his 70s. Musk may attempt a trip to Mars decades sooner, but unless there are miraculous biological advances soon, he will die in the attempt. Perhaps better than facing angry investors.

Aldrin's schedule is ambitious as well; Mars is 1000 times further away, and the journey will take 70 times as long as Apollo. We will need a lot of capability in place to support the eventual arrival of humans. Phobos is a good first goal; the delta V to Mars surface and back is around 9 km/s, a significant fraction of an Earth/Moon mission with no Mars-local infrastructure to support it.

The best idea in the book is synchronous cyclers, small space habitats with shielding and infrastructure to support astronauts between Earth and Mars orbit. The cyclers will need to be supplied from Earth with consumables and propellant, ditto for the Mars outpost at the other end. They will also require "escape velocity plus" delta V to reach at both ends, plus additional thrust on the cycler itself to keep it in an orbit that synchronizes with both Earth and Mars.

I don't expect Dr. Aldrin to agree, but launch loops capable of putting megatons into high orbit might be a good way to assemble a cycler and launch it into its interplanetary cycle, and would have enough delta V to supply a cycler directly as it flies by near Earth. A 5 tonne launch loop could make many launches towards the steadily changing position and velocity of the cycler, with many chances for error ... or cumulative success, assembling kilotonnes of components for cyclers. In time, experience and automation will reduce those errors.



Page 154-157 of the book discusses robotic telepresence in hopeful words. Aldrin mentions UT Austin astronomer Dan Lester as a champion of exploration telepresence, and S. Fred Singer as an advocate of surface landers controlled from Phobos or Deimos via relay satellites. From Phobos, I figure that to be a 39000 km, 130 millisecond maximum round trip, as opposed to a 0.7 hour maximum round trip from Earth; an excellent opportunity for telepresence. If we develop 2.7 second predictive-adaptive telepresence from Earth to Moon, and 50 millisecond lunar orbit-to-surface telepresence, we will have excellent tools to do this.

We will eventually visit Mars, and we will find surprises (that is, not what we were looking for). It is unlikely humans will create long term independent settlements there; there are no advantages over space habitats, and there is no reason to leave the Earth gravity well just to trap ourselves down another one.

The best "use" of Mars is as an object of study, and as a target for trajectory-modified ultra-precision-targeted asteroids that might otherwise become dangerous Earth impactors in the far future. Rather than the THOR Mars penetrators he writes about, there are a vast number of massive asteroid "penetrators" that can (with much patience) drill into Mars as deeply as future scientists could hope for. There's not enough total mass in the entire asteroid belt to significantly enlarge Mars, nor can they be delivered fast enough to heat the planet to shirt-sleeve temperatures, but it is better that they hit Mars rather than someday hit the Earth.

I don't agree with Dr. Aldrin about many things, but he writes informatively. I don't think we will spend vast sums on non-profit space projects without a geopolitical threat, and ... I don't like scads of labored acronyms.

Namedrops

BuzzAldrin (last edited 2017-04-26 03:17:05 by KeithLofstrom)