Exoplanet Atmospheres Observations. Mercedes López-Morales Harvard-Smithsonian Center for Astrophysics

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1 Exoplanet Atmospheres Observations Mercedes López-Morales Harvard-Smithsonian Center for Astrophysics

2 Planets versus Year of Discovery PSR d PSR c Earth PSR b Total: 1849; Transiting: 1163

3 HARPS-N Collaboration Francesco Pepe, Andrew Collier Cameron, David W. Latham, Emilio Molinari, Stéphane Udry, David Charbonneau, Mercedes López-Morales, Christophe Lovis, Michel Mayor, Giusi Micela, David Phillips, Giampaolo Piotto, Didier Queloz, Ken Rice, Dimitar Sasselov, Damien Ségransan, Alessandro Sozzetti, Andrew Szentgyorgyi, Chris A. Watson, and many collaborators... Sanchis-Ojeda et al. 2013, Howard et al. 2013, Pepe et al g cm g cm 3 Neptune 4.0 g cm 3 Water Radius (R Earth ) g cm g cm 3 Rock Iron 1 Kepler-78b (8.5h, 1.7M E, 1.1R E ) Mass (M Earth )

4 Planets versus Year of Discovery PSR d PSR c Earth PSR b Total: 1849; Transiting: 1163

5 How we detect exoplanet atmospheres Via Direct Imaging HR 8799 b, c, d Via Transits Secondary Eclipse Primary Eclipse Secondary'eclipse' (<'0.1'='0.2%'of'total'light)' (Marois et al. 2008) Primary'eclipse'(~'1%'of'total'light)' Atmospheric characteristics!temperature (T p ) Albedo (A B = 0 to 1) Winds (f or P n = energy re-distribution factor) f= 2/3 = No re-distribution (P n = 0.0) f= 1/4 = homogeneous re-distribution (P n = 0.5) Chemical composition!!

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7 First Exoplanet Atmosphere Detections First detected by Charbonneau et al. (2002) Sodium doublet 2nd & 3rd contact 1st & 4th contact Planet Radius Wavelegth Difference of relative fluxes Note: The depth of the Na absorption was ~ 3 times shallower than predicted for clear atmosphere models. Proposed by Seager & Sasselov (2000)

8 Relative Flux Relative Flux First Exoplanet Atmosphere Detections 24 μm (HD b) (Deming et al. 2005) 8 μm (TrES-1b) (Charbonneau et al. 2005) Time Time Teff ~ /- 150 K Teff ~ /- 50 K

9 Collage of exoplanet atmosphere measurements from space until 2010 (from Seager & Deming 2010)

10 HST+Spitzer Transmission Spectrum of HD189733b The spectrum appears dominated by Rayleigh scattering and a cloud deck Pont et al. 2013

11 Transmission Spectrum of super-earth GJ1214b Transmission Spectrum of hot Neptune GJ436b Kreidberg et al Knutson et al. 2014

12 Exoplanet atmosphere observations from the ground Cons: Mainly the Earth s atmosphere Pros: Many telescope facilities, many observing modes and larger photon collecting areas

13 Detections thus far From Space: - Spitzer Space Telescope - Hubble Space Telescope From the Ground: - HET, CFHT, 3.5-m APO, Magellan, VLT, GTC, etc!!!!!! Successful Techniques: - Standard (single filter, broadband) differential photometry. - Tunable filters (narrow band) differential photometry. - Differential Wide (+long) slit spectro-photometry (low resolution). - Differential multi-slit spectro-photometry (low resolution). - Very high resolution (narrow band) spectroscopy.

14 The First Ground-based Detections Ground-based detection of Sodium in HD b (Redfield et al. 2008) With Ground-based detection of Sodium in HD b (Snellen et al. 2008) Ground-based confirmation of Sodium in HD b (Snellen et al. 2008) Δλ!=!3.0!Å!!!!!!!!!!Depth!=!0.056%!! Δλ!=!0.75!Å!!!!!!!!!!Depth!=!0.135%! >!5σ!detec4on! With ** More recently, detection of Na I in WASP-17b (Wood et al. 2011; Zhou & Bayliss 2012).

15 The First Ground-based Detections Ogle-TR-56b (Sing & López-Morales 2009) TrES-3b (de Mooij & Snellen 2009) z #band!(0.9!µm)!!!!!!!!!!!!!!depth!=!0.036%!(3.6σ)! K#band!(2.2!µm)!!!!!!!!!!!!!!!Depth!=!0.241%!(~6σ)! T z = 2718 ± 120 K A B ~ 0.0 (no-clouds) f ~ 0.56 (low winds) Thermal Inversion?!!)! T k = 2040 ± 185 K A B ~ 0.0 (no-clouds) f ~ 2/3 (low winds) Thermal Inversion?!!)!

16 A flat transmission spectrum for GJ1214b! "Featureless"spectrum."! "Atmosphere"must"be"at" least"70%"h 2 O"by"mass,"or" have"op<cally"thick"high" al<tude"clouds/haze." With FORS,HAWKI@VLT and MMIRS@Magellan Bean et al. (2010,2011), Berta et al. (2011), Croll et al. (2010), Fraine et al. (2011)

17 Potassium detection in XO-2b and HD b XO-2b Sing et al HD 80606b Colón et al Traub 2009 Both detections with OSIRIS@GTC s Tunable Filters

18 Tentative Sodium detection in XO-2b Haze/Cloud free atmosphere. Atmosphere with Haze/clouds obscuring the Na line wings. CCD spectrum of XO-2 A and XO-2 B observed simultaneously with OSIRIS@GTC with R500B grism and 5 wide slit. Sing et al. 2012

19 A few more optical transmission results WASP-29b HAT-P-32b Gibson et al. 2013a Gibson et al. 2013b Detections with & Gemini-S. Both planets show featureless spectra. - No Na I rich, free of clouds atmosphere - Clouds or haze present - No Na I rich atmosphere is the most likely case, given Tp ~ 970K. - No Na I or K I wings or prominent TiO/ VO features. - Grey absorption clouds in upper atmosphere likely - Cannot rule out clear atmosphere models with low abundances.

20 Some facts are unveiling... Planets with Na I or K I detections Planets with featureless spectra (clouds/hazes) 8 11 Charbonneay et al. 2002; Colon et al. 2010; Crossfield et al. 2013; Gibson et al. 2013; Jordan et al. 2013; Knutson et al. 2014; Kreidberg et al. 2014; Mancini et al. 2013; Murgas et al. 2013; Snellen et al. 2008; Sing et al. 2010, 2012, 2013; Zhou & Bayliss 2012.

21 6.5-m Magellan 10-m GTC 8-m VLTs The Future 24.5-m GMT 30-m TMT 39.3-m E-ELT

22 ACCESS: The Arizona-CfA-Catolica Exoplanet Spectroscopy Survey (PI: López-Morales; Institutional Co-PIs: Apai & Jordán) ACCESS will generate the first uniform observational database of microns transmission spectra of exoplanets from hot Jupiters to Super-Earths.

23 Detection of the atmospheres of non-transiting planets 2! Tau!Boo!b! 1! 3! Tau!Boo! Obs.!!Rodler,!López-Morales!&!Ribas!2012!!Brogi,!Snellen!et!al.!2012! Atmospheric CO lines Doppler shift Full details in Florian Rodler s talk

24 Detection of biomarkers in transiting Earth analogs

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26 Rodler & López-Morales (2014) Snellen et al. (2013)

27 Rodler & López-Morales (2014)

28 Summary - After discovering almost 2000 exoplanets, this field is now expanding into the study of the planet s atmospheres - The first detections of exoplanetary atmospheres were done from space, but since 2008 we are now also able to study atmospheres from the ground - Observations of transmission spectra of Jupiters so far seem to indicate the presence of clouds - The only super-earth and Neptune study in detail seem to show flat transmission spectra, indicating thick high altitude cloud decks. - This field is still in its infancy, but there are new techniques and ideas to detect exoplanetary atmospheres that will further advance this field in the TESS and ELTs era.