The Search for Extra-Terrestrial unIntelligence Jonathan Tennyson Department of Physics and Astronomy University College London "The two most common things in the universe are hydrogen and stupidity." Harlan Ellison

Is there anybody out there? Sagittarius Star Cloud / Hubble Space Telescope At least 100 thousand million (10 11 or ) stars in the milky way At least 100 thousand million (10 11 or ) galaxies in the universe

How to find aliens 1. Hope that they visit us 2. Listen for their signals 3. Look for them

Search for extraterrestrial intelligence (SETI) The Arecebo telescope

SETI: >500,000,000 screensaver downloads and counting ……What has been found? Nothing

Extra solar planets

Kepler (the mission) Earth-size planet transiting Sun-type star ~ 0.01 % Kepler (NASA) launch 2009

10 More than 1200 planetary candidates discovered by Kepler! Exoplanets are common…

Jupiter—Sun: 15 m/s Present sensitivity: 1 m/s Earth—Sun: 0.09 m/s

You are here! Characterizing extrasolar planets

Habitable zone for different stars “Goldilocks zone”

Earth and moon from the Galileo spacecraft Can one detect the signature of life on Earth?

NASA’s Galileo Satellite Launch 1989 Arrived at Jupiter 1995

“Flatulent ruminoids” Segan et al, Nature (1995)

100 million+ years ago – Plenty of methane emissions?

Time (Gy) Oxygen Multicell- Human s Invertebrates Rye and Holland, 1998 Oxygen!!! Eukaryotes Prokaryotes Methane ?

How far is it to the nearest star? A long way!

“ We will never know how to study by any means the chemical composition (of stars), or their mineralogical structure ” Auguste Comte (1835)

Fraunhofer ’ s map of the solar spectrum

High resolution optical spectrum of the Sun

EmissionAbsorption Level 3 Level 2 Level 1 photon Energy Jumping between energy levels in an atom or molecule

Methane in the Earth’s atmosphere Before photosynthesis After photosynthesis

A pale blue dot, at 6 billion km away… (  ) C. Sagan

Direct observation 10 9 photons in the VIS -> Coronagraph 10 6 photons in the IR -> Nulling interferometry Direct observation of star GQ Lupi and its planet GQ Lupi b

Transit of Venus June 8th Next June 5th 2012.

Radial velocity / Occultation Period = days Mass = 0.69 ±0.05 M Jupiter Radius = 1.35 ±0.04 R Jupiter Density = 0.35 ±0.05 g/cm 3 HD b

NASA’s Spitzer space telescope

Beaulieu et al., 2007 Knutson et al., 2007 Primary transit + IR + Spitzer

Water, T-P at the terminator Water line list: BT2 Barber et al., 2006 Tinetti et al., Nature, 444, 169 (2007)

Methane, plus Confirmation of water and hazes! Beaulieu et al., 2007 Knutson et al., 2007 Swain et al., 2007 Pont et al., 2007

Giovanna Tinetti, UCL So far discovered: Water H 2 O Methane CH 4 Carbon dioxide CO 2 Carbon monoxide CO Hydrogen cyanide HCN On HD189733b with more to come HD b too hot for life

Transit hunters Transits of objects down to Earth-size COROT (CNES/ESA) launch Dec (mission extended) 25 transiting planets found including 1 super-earth Kepler (NASA) launch 6 March year mission: 22 confirmed planets so far + >1200 candidates

NWO is a large-class Exoplanet mission that employs two spacecrafts: a “starshade” to suppress starlight before it enters the telescope and a conventional telescope to detect and characterize exo-planets. Cash, Nature, 2006 The New World Observer

Exoplanet Characterisation Observatory Telescope Baffle V-groove side sunshield GaAs Solar Cells Detectors Service Module 1.5m silicon carbide mirror

Exoplanet Characterisation Observatory 1.2 to 1.5m dedicated telescope L2 halo orbit, direction anti-Sun Broadband spectral coverage from VIS to IR ( 0.4 to 16 µm ) Maximum spectral resolution R=300 5 year mission PI Giovanna Tinetti (UCL) launch 2022?

A year in the life of July 10 Talk WCGS Science Conference July 10 European Space Agency (ESA) formal call for M3 missions Oct 10 European Research Council (ERC) awards me 2.5 MEuros for ExoMol: Molecular line lists for exoplanet & other atmospheres Nov Expressions interest to ESA Dec Formal bids to ESA Jan bids selected (including EChO) Feb 11 8 bids selected (including EChO) March 11 4 bids selected for further study: EChO, LOFT, MarcoPolo-R, STEQUEST May 11 ExoMol project starts June 11 UK Space Agency + PPARC select EChO as top priority

Future timelines (approximate) Specification and testing 2014 “Down selection” Instrument and satellite build Assembly and testing 2022 Launch ?

H 3 + Liesl Neale (H 2 D + Taha Sochi )‏ H 2 O Bob Barber (HDO Boris Voronin )‏ HCN/HNC ( H 13 CN/ H 13 CN ) Greg Harris HeH + Elodie Engel NH 3 Bob Barber and Sergei Yurchenko (Dresden)‏ HCCH Andrea Urru C 3 Santina La Delfa and Taha Sochi Linelists completed or under UCL by The ExoMol project