Breakthrough Discuss 2019 (1/3): Bite-Sized Thoughts

Over the past few days, I’ve been attending the Breakthrough Discuss 2019 conference in Berkeley, California. In general, the conference focuses on space exploration and the search for life in the universe, and this year’s theme was “Migration of Life in the Universe”. As of a few months ago, I’ve been trying a new strategy of condensing my conference thoughts into blog posts in order to record and order my thoughts and share the things I learned. I’m already behind – my AAAS 2019 series is unfinished, first post here. This time, however, I’ve decided to publish all three of my posts about Breakthrough Discuss at once.

This first post is a scattershot of interesting one-off notes: facts and figures that I learned, papers and resources that I will refer to in the future, quotes I liked from the speakers, and new jargon that I absorbed.

Numbers I learned:

  • In order to see observational evidence of the carbonate-silicate cycle on exoplanets, we would need observations of 11-51 different Earth-like planets in the habitable zone with LUVOIR. This is surprisingly doable!
  • Breakthrough Listen has a shiny new Open Data Archive, and you can download filterbank and raw voltage files from it. I get the feeling that Penn State might not be happy if I try to download 400 TB of FRB baseband data to the ACI cluster, though.
  • From argon-argon dating, shock petrology, and paleomagnetism, we can infer that some Martian meteorites have been heated up to 80C on the outer few millimeters, but no hotter.
  • The impact flux (rate at which meteoroids impact the Earth) was probably 500X higher at 4 Gya.
  • Life could probably be okay in a meteorite for ~10 Myr timescales.
  • According to Steve Benner, Earth probably had a ~0.25 Gyr window in which it could develop life.
  • At 3 Mya, human brains experienced a neocortical expansion by a factor of 3.
  • If ‘Oumuamua is representative, ~100 interstellar objects have likely impacted the Earth throughout its history.
  • Bacteria can self-replicate in 20 minutes.

Facts I learned:

  • The reason we see so many small bodies in mean motion resonance with Neptune is probably from resonance sweeping during Neptune’s migration (which is good evidence for this migration in the first place).
  • The Murchison meteorite smells like a sulfurous oil well because it’s so full of organics.
  • There is a gene called NOTCH2NL which is only found in humans. The Human Genome Project accidentally reported an incorrect place for it in the genome, leading to it being unexamined for years. Later, when the data was rerun, it was shown that NOTCH2NL actually resides in the macrocephaly region. Its appearance lines up with a massive increase in brain volume.
  • The insides of partially differentiated small bodies might be warm, wet, and organic-rich for tens of millions of years. This allows them to be potential carrying-cases for single-celled life!
  • There are four big challenges to be overcome in the process of panspermia:
    • 1) High temperatures during ejection could sterilize any fragments that did harbor life.
    • 2) Reaching escape velocity could cause high accelerations that would squash life.
    • 3) The vacuum / low pressures of space could desiccate life.
    • 4) The radiation environment of space could fry life.
  • The configuration of the solar system is far from optimal with regards to panspermia. The best case scenario would be a small central star, tightly packed planets, and resonances between those planets.
  • Resurfacing on the Earth implies that the oldest Earth rocks that we’ll find are actually on the Moon!
  • There are many genes (junk DNA) that are conserved in human DNA and we don’t know what they do.
  • Staph is no longer a pathogen in orbit, but salmonella is more pathogenic in orbit.
  • We have no idea how much continental crust existed in the Hadean (see figure).
Figure 1 from Korenaga 2018b showing how much models of Earth’s continental crust formation vary.

Papers I’m interested in reading:

Resources I became aware of:

  • Announced just weeks ago, Sandra Faber is putting together an Earth Futures Institute at UC Santa Cruz, thinking about sustainability and human systems over a million year timescale.
  • Foundational Questions Institute – An institution interested in supporting research on innovative physics/cosmology questions unlikely to be funded by other sources. Hmmm…
  • Sara Walker’s research group, Emergence, is focused on trying to find laws of life and applying them to astrobiological questions.
  • Oxford Nanopore – Tools that make genomic sequencing easy for anyone, anywhere.
  • DARPA Safe Genes – An organization thinking about research and integrated policy to prevent intentional or accidental genetic disasters, before we get to the point where we have the ability to make them happen.
  • Chris Kempes and Sarah Maurer are teaching an Origins of Life MOOC directed at first-year grad students starting in June!
  • Natalie Batalha directed the audience to a piece of art called the Map of Technological Ethics by Qiu Zhijie. This 2018 work, to me, really helps visualize the immense, inherent complexity of the issues that we cannot avoid as scientists (and as humans). And in this piece, each small region of the map – each label – represents an incredibly complex and unresolved issue or concept. When we think about the evolution of intelligence / complex life, we have to explain a sentient system that deals with all of this – talk about emergence! It also provocatively asks “Why do we want to escape from Earth?”

Map of Technological Ethics

Ahh, Anthropocentrism Lake, just west of Anthropocene Coast and southwest of Man-Made Doomsday Delta.

Great quotes:

  • “Who lives, who dies in this Anthropocene?” – Natalie Batalha
  • “I used to measure the shadows of Earths” – Kepler (yes the telescope, epitaph)
  • “Self-sustaining artificial life is seen as a threat” – Steve Benner
  • “The complexity of human society is far less than eukaryotic complexity” – David Haussler
  • “The worst place you can go on Earth is still infinitely better than plopping yourself down on Mars” – Lynn Rothschild, on why Mars is not a “Planet B”.
  • “Europa is basically an ice bedrock roof cave environment” – Penny Boston
  • “We need to explore for the right reasons” – Natalie Batalha

And my personal favourite:

  • “I’ve always wanted to be photosynthetic” – Penny Boston

New jargon I learned:

  • Spallation: “A process in which fragments of material (spall) are ejected from a body due to impact or stress” (Wikipedia). When talking about impactors hitting planetary bodies, this provides a relatively gentle way to get material just up to escape velocity, and thus provide a reasonable vector for panspermia.
  • Steppenwolf Planet: A planetary-mass object that orbits the galactic center directly (is not bound to a star) and could be habitable, thus providing another vector for life to travel throughout a galaxy. Synonym for rogue/free-floating planets coined in a 2011 paper.
  • Hachimoji DNA: A synthetic kind of DNA (and RNA) that has two synthetic base pairs (based on four synthetic nucleotides) in addition to the the four normal nucleotides. Gives DNA additional capacity to store information, and opens up new avenues for extraterrestrial life.
  • Bespoke Chemistry: Custom-made chemistry (I think?) that allows us to think about the origin of life from a synthetic biology perspective.
  • Optogenetics: A technique in genetics where cells (usually neurons) are genetically modified to activate in response to light, giving a way to precisely control and study them in the lab. Helps us learn about the development of intelligence.
  • Radioresistance/Radiotroph/Radiosynthesis: In order, organisms that can withstand a high-radiation environment (ex. Deinococcus radiodurans and tardigrades), organisms that harvest energy from radiation (ex. fungi around Chernobyl which actually need radiation to survive), and the process by which organisms harvest energy by radiation. Organisms that get their energy this way could thrive even in the high-radiation environment of space.

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Part 2 of this blog series provides a more in-depth look at some conceptual ideas that I’ve been thinking about since the conference!