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A 500 year Grand Plan for going to the stars ... at very high acceleration and speed, as space-tolerant acceleration-proof sorta-kinda awake-and-aware human beings. A 500 year Grand Plan for going to the stars ... at very high acceleration and speed, as space-tolerant acceleration-proof sorta-kinda awake-and-aware human beings.  Sounds like a lifetime in prison.

The Next 500 Years

Engineering Life to Reach New Worlds

2021 Christopher E. Mason @ Weill Cornell Medicine

612.0345 MAS / Beaverton Library

A 500 year Grand Plan for going to the stars ... at very high acceleration and speed, as space-tolerant acceleration-proof sorta-kinda awake-and-aware human beings. Sounds like a lifetime in prison.

I recently discarded a stack of 20 year old electronic engineering magazines, with articles describing how the new Zigbee standard would soon overtake the old Bluetooth standard. Today, Zigbee is wide spread, but Bluetooth is VASTLY wider spread. Predictions are hard, especially about the future.

Indeed, humans will modify themselves to thrive in the space environment. Not so our descendants can travel to a planet around another Sun, but so that life and mind can thrive in the other 99.99999999% (yes, ten 9s) of the solar system that lacks matter but is awash in sunlight energy. We've outgrown the Earth as a cradle of life; we can create vastly more opportunities in the inner and outer solar system, while restoring our cradle to health, so it can birth future species, and perhaps new varieties of intelligence.

Yes, the Sun will become much hotter over the next ten billion years. "At the end of the next 4.8 billion years, the Sun will be about 67% brighter than it is now. In the 1.6 billion years following that, the Sun's luminosity will rise to a lethal 2.2 Lo". A tiny tiny fraction of Earthlife can go elsewhere, in a few miniscule and outrageously expensive lifeboats, while 99.999% of life and intelligence remains on Titanic Earth perhaps as string quartets performing "nearer my God to thee".

Or ... over the next 4.8 billion years, we increase the orbital radius of the Earth by 30%, towards the orbit of Mars, reducing insolation from 1.67 to 1.0, as now. That is a slower orbit; the year will increase to 541 days. The Earth's orbital angular momentum must increase by 14%. Over the next 6.4 billion years, we can increase the Earth's orbit radius to 1.48 AU (and nudge Mars a bit farther out of the way, or disassemble it into habitable asteroids). That will increase angular momentum by 22%, and result in a 658 day year. Around this point, the Sun starts burning helium, expanding 1000x from the present size, approaching the orbit of Jupiter - time to finish evacuating the Earth. But not as acceleration-armored humans, we will self-evolve into information-dense forms and scatter beyond the Kuiper belt. NO HURRY ... 6 billion more years is an excellent prognosis for a living planet, properly maintained.

The solar system contains many bodies with a lot of angular momentum and orbital energy; we can arrange asteroid flybys to extract some of that, and flybys of Earth to move it outwards towards the cool. With proper engineering and continuous maintenance, our Mother Earth might survive another 6 billion years. The crown jewel of an aware solar system, using all the rest of the Sun's energy to power an enormous constellation of lifeforms and intelligence, thriving in zero gee, vaccuum. and ionizing radiation from the Sun. With the huge time available, and with vastly more energy and resources, "we" (the intelligent beings we artificially evolve to become) we will learn many more ways to live.

p37 Metagenome Mapping: estimating trillions of species on Earth (mostly microbes). The Earth Microbiome Project and the Extreme Microbiome Project sequence and create taxonomies for microbes around the world. Dr. Mason's MetaSUB and the MoBE search for and sequence microbes adapted to our urban environment. The Darwin Tree of Life Project will sequence 70,000 eukariotic species in the UK. If this is "stamp collecting", we will use those stamps to mail intelligent life into the rest of the solar system, and after that the stars.

This will take longer than 500 years. Intelligence will grow prodigeously, but there are vastly many niches to fill in our own solar system before it is necessary to find other niches, around other stars vastly further away.

p100 "There is a planned apace station for orbiting Mars ... Lockheed Martin in 2040". Er, no. Unmodified humans require gravity, and radiation shielding. Too heavy to launch from Earth to Mars. On the other hand, Phobos may be an excellent place to dig in and shield a one-gee rotating habitat.

p176 reflecting badly:

  • Breakthrough Starshot: Yuri Milner, Stephen Hawking, Mark Zuckerberg. Starchip: Kevin Parkin 2018
  • Proxima Centauri B, 4e16 meters away. "25 years to get there with a 100 GW laser, 25 years to return the data"
  • A centimeter/gram scale spacecraft with a 4x4 meter lightsail propelled by a 100 GW laser. That is 6 GW per square meter. A hypothetical super-mirror form of carbon might withstand 3000C. Presuming "superblack" albedo zero on the starward face, that is a black body emission of less than 5 MW per square meter from that face. So the supermirror must have better than 0.999 reflectivity. If it masses half a gram, at 2 grams per cubic centimeter, that is a thickness of 16 nanometers ... which somehow must have a bending moment that keeps it absolutely flat and perpendicular to the incoming laser beam.
  • Consider how this tiny object can aim any data photons at all back to Earth. Presumably, this is a high speed flyby through the Proxima system at 0.2C. Proxima's luminosity is "50 microsuns", deep in the red; a planet in the so-called habitable zone would be 1 million kilometers from Proxima, and would be in view for milliseconds. "25 years to return the data" presumes that an onboard radioisotope generator will maintain transmission for the next 25 years, between 4.3 and 8.6 LY distance. If that (somehow) uses the shiny sail as a super-duper parabolic dish, and 500 nm photons, the beam at 8.6 light years distance will be 12 million kilometers wide, about 1e20 square meters. If the transmitter produces 1 watt of 500nm photons, that is 2.5e19 photons per second, or 1 photon per 4 square meters of receiver ... 1 photon per Earth receiver square meter during Proxima transit. However, Proxima itself is 2e22 watts; emitted isotropically, that is 1 picowatt per square meter at Earth of black body photons, maximum flux at 900 nm wavelength, with considerable flux at 500 nm, millions of photons per second. The receive mirror must have incredible angular discrimination to "see" a tiny probe's signal at that distance, presuming the probe flies close enough to Proxima for its tiny optics to see something.
  • That all presumes transmitter mirror and receiver are optically perfect, zero Strehl scattering. Seems unlikely, after that mirror was baked by a 100 GW beam during launch.
  • PRE-frigging-POSTEROUS!

p218 launch of a generation ship, four centuries from now, and the gene engineering of humans for that ship. Given the outlandish physics preceeding this chapter, the human biological engineering seems absurdly tame, especially compared to "Regenesis" by George Church (who is mentioned nine times, but not cited). Amusing comparison of "editing hesitancy" to "vaccine hesitancy".

p242 brief mention on scanning for "water" on Mars. Water may be bound in smectite clays, practically unavailable.

Next500Years (last edited 2022-01-03 01:29:50 by KeithLofstrom)