New Frontiers: Big Questions Conference IV

Continued slow liveblog of the New Frontiers in Astronomy and Cosmology Conference at the Franklin Institute.

Lunch is almost over and we are headed into the final session of research presentations, clearly saving the best for last...
I am also reminded why we have these meetings, in person, the chats during break and back and forth in sessions provides very dense information transmission and tight feedback loops on news.

Big Question IV - Are we Alone in the universe?
Or, are there other life and intelligence beyond the solar system?

1) Jonathan Lunine from Cornell on "The search for life in extremely exotic environments: a strict test for life's cosmic ubiquity"

Life on Titan - looking for seaparate origins life in the solar system, in extreme environments natch.
There is Oil On Titan!
Frack Titan Now!

Interesting NRC Report "Limits of Organic Life" (2007)

This particular project to do lab and simulated biochemistry for Titan environment.
Build rationale for Titan mission.

NB: I agree with Titan as a promising target for alternate biology, been some very interesting speculation on CH_n metabolisms and there is the tantalising hint of the ethylene gradient in Titan's atmosphere, consistent with predictions assuming significant surface metabolic activity.

2) Geoffrey Marcy from UCB on "Discovery of Earth-like Planets and Signals from Intelligent Life"

Alternative SETI techniques:

i) ***LASER*** emission from ET
spectroscopic search for laser emission, per Schwartz & Townes (1971)
MW-GW lasers at nearby stars detectable with 10m telescopes
'course they have to be pointing in our direction...

Long slit spectroscopy - 14" slit on Kepler field stars with known exoplanets.
Coherent narrowband optical emission jumps out.

Also looking for seriously powerful lasers from nearby galaxies!
Would require ~ 10¹⁸++ W lasers - eh, that is only 10²⁵++ erg/sec. Piece of cake.
They should search at our targets... seriously

NB: surely Kepler detected planets will NOT be that likely to be looking at us with AU guide lasers etc. we are in their ecliptic! They'll be looking at high local latitude, away from us...

ii) Looking for shadowing by partial occlusion by non-natural structures in Kepler data, some interesting candidates already

-- weird brightness fluctuations
These look v. cool

Ok, into the homestretch, and we are back from the break:

3) Lucianne Walkowicz from Princeton on "Stellar Lighthouses: Decoding Signatures of Advanced Civilizations in Precision Stellar Photometry"

Signs of Arbitrarily Advanced Civilizations from stellar variations.

Data outstripping our ability to analyse.
Look for unknown unknowns - data mining.

Look for signatures of AACs in already existing databases.

Also. Think about what to look for.

Look for outliers. Natch.

Sub-KII engineering - planet/star energy harvesters that modulate
stellar output.

NB:
"I have never seen a green star
I hope one day we see one..."

- there is an old Analog story about the discovery of chemically peculiar star, turns out its convective zone is spiked with manganese - further search reveals more weird unnatural stars, including one bright green one - the conclusion is Alien Pranksters...

4) Jason Wright from Penn State on "Constraining the Abundance of Kardashev Type II and III Civilizations From Large Area Infrared Surveys"

Keeping up with the Kardashevs

Kardashev at AstroWright op cit.

To recap:

some civilizations will want to do energy intensive long term projects

starlight, and possibly black hole accretion, is the predominant source of power (modulo dark matter/dark energy engineering which is beyond the scope of this project)

AACs are constrained by laws of physics, especially conservation of energy and thermodynamics

once the free energy has been extracted the waste heat must be radiated away, some fraction in photons

this is detectable as mid-IR emission, unless deliberately shielded

we can parametrise the emission depending on the efficiency
it is currently detectable

K3 civilizations are detecable in the local universe
K2 civilizations are partially detectable in the very local part of the galaxy

we can put potentially interesting quantitative constraints or upper limit on the abundance of K3 civs in the local universe and to some extent the K2 civs nearby

the systems selected are astrophysically interesting if not artifacts

and we are done.