penn state astrobiology research center...
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Penn State Astrobiology Research Center (PSARC)
Christopher H. House, Ph.D.
• Astronomy: Sigurdsson, Wright, Mahadevan,
and the PSU Center for Exoplanets & Habitable Worlds
• Atmospheric Chemistry: Lyons (UCLA) & Kasting
• EPO: Heather Nelson & the PA Space Grant Consortium
• Evolutionary Genetics: Hedges & Shapiro
• Geobiology: Macalady, Orphan (Caltech), Patzkowsky, House, & Schopf
• Geochemistry: Arthur, Brantley, Fantle, Freeman, Kump,
McKeegan (UCLA), & Ohmoto
• Microbiology and Biochemistry: Bakermans, Brenchley, & Ferry
61 PSARC Completed Ph.D. Students N. Suits ’98; L. Brown ’99; A. Pavlov ’01; B. Borup ’01; S. Ono, ’01; P. Iver ’01; R. Hotinski ’02; M. Van Tuinen ’02; K. Yamaguchi ’02; Y. Watanabe ’02; H. Pointkiviska ’03; M. Borda, ’03; M. Hurtgen, ’03; S. Lawrence, ’04, A. Herrmann, ’04; F. Cruz, ’04; S. Shipkowski ’05; P. Kharecha, ’05; J. Blair, ’05; J. Eigenbrode, ’04; J. Debes, ’05; H. Buss, ’06; J. Biddle, ’06; A. Zerkle, ’06; Z. Krug, ’06; A. Smirnov, ’06; C. Cohn, ’06; C. Turich, ’06; S. Stafford, ’06; J. Moran, ’07; E. Herman, ’07; D. Hydutsky, ’07; S. Zimmerman, ’07; S. Goldman, ’07; M. Bachmann, ’07; K. Panchuk, ’07; A. Mandell, ’07; A. Riccardi, ’07; F. Battistuzzi, ’07; V. Cameron, ’08; L. Hausrath, ’08; B. Thomas; ’08, K. Meyer '08; A. Edson ’08; L. Horodyskyj ’09; E. Patridge ‘09; E. Beal ’09; M. Heinicke ’09; K. Moody ’09; B. Kimball ’09; M. Reichlen ‘10; J. Fulton; ’10; C. Junium ‘10; M. Wang ‘10; A. Diefendorf ’10; Haqq-Misra, ‘10; K. Dawson, 11; D. Jones, ’11; M. Rhodes ’11; Alexis Navarre-Sitchler ’11; Heidi Albrecht ’11
Education and Public Outreach • Undergraduate Minor & Ph.D. dual-title Program • Teacher professional development workshops • Exploration Day • Museum exhibits and events • Citizen Science Project on “Thermophiles in Your Basement”
NASA Missions related to Astrobiology
Mars Science Lab (and follow-on program)
Europa Orbiter
Mars Trace Gas Orbiter
Kepler
Titan Lake Lander
Enceladus Orbiter
PSARC (Penn State, UCLA, & Caltech): Signatures of Life from Earth and Beyond (2009-2014)
1. Developing new biosignatures
2. Biosignatures in relevant microbial ecosystems
3. Biosignatures in ancient rocks
4. Biosignatures in extraterrestrial settings
Topics to cover:
• Developing New Biosignatures
DNA in deep marine sediment (House)
• Biosignatures in relevant microbial ecosystems
Microbial Signatures of Ancient & Extraterrestrial Oceans (Macalady)
• Biosignatures in ancient rocks
Large-scale Perturbations of the Paleoproterozoic Carbon Cycle (Kump)
• Biosignatures in extraterrestrial settings
The Quest for Terrestrial Mass Planets around M dwarfs with Near-Infrared Spectroscopy (Mahadevan)
DNA in deep marine sediment
• Nucleic acids as signatures of life
• IODP – unique environments and samples
• A Paleome?
Nucleic acids as signatures of life
IODP – unique environments and samples
C0014 500 m east of vent
Okinawa hydrothermal mound
IODP – unique environments and samples -High productivity
margin environment
-Upper plate of subduction zone, unique in historical changes from accretionary to erosive type
-2 sites extending to around 500 (site 1378) and 700 (site 1379) meters below seafloor
A Paleome?
Willerslev and Cooper, 2005
A Paleome?
Astrobiology. 2005, 5(2): 141-153. Terrestrial Cretaceous black shale with marine microbes
Microbes in ancient ice and ocean sediments
Price, 2009
A Paleome?
Conclusions
• DNA is the ultimate biosignature on Earth
• DNA seems to be preserved in ancient marine sediments
• Ocean Drilling provides Astrobiology with great opportunities
14 Photo Wes Skiles
Microbial Signatures of Ancient and
Extraterrestrial Oceans
Kump (2008)
16
Conical Stromatolites
Photo J. Macalady
Or, cones may be the result of gas bubbles
enmeshed by a web of filamentous cells.
Macalady et al., in prep.
Magical Blue Hole Geochemistry
Photo Brian Kakuk
Photo Brian Kakuk
Magical Blue Hole
• Extensive biofilm with abundant
cones
• No cyanobacteria
• Long filaments abundant, but
likely heterotrophs
20
McCauley, Macalady et al. in prep.
21
Photo Brian Kakuk
Chlorobi
(non-filamentous,
anoxygenic photoautotrophs)
sulfate-reducing bacteria
planctomycetes
candidate divisions GN1, OP11, TM6, WS3, OP8, OP3
Chloroflexi
Magical Blue Hole
Bacterial 16S rRNA
22
Photo Brian Kakuk
Conclusions
Observation:
Neither oxygen production nor cyanobacteria are required for cone formation.
Interpretation:
Conical forms must be either
1) a general biosignature of gas exchange (but no bubbles observed),
or
2) a fundamental reflection of physics and chemistry of diffusion limitation in biofilms
23
Large-scale Perturbations of the Paleoproterozoic Carbon Cycle
Lee Kump, Christopher Junium and Michael Arthur
Department of Geosciences, Pennsylvania State University
Alex Brasier and Anthony Fallick
Scottish Universities Environmental Research Centre
Victor Melezhik, Aivo Lepland and Alenka Črne
Norwegian Geological Survey
Genming Luo
China University of Geosciences
and the FAR-DEEP Drilling Team
Kump (2008)
Kump and Barley (2007)
Fike et al. (2006)
Shuram-Wonoka Excursion
Melezhik V A et al. Geology 2007;35:655-658
©2007 by Geological Society of America
-----MIF----|
Victor Melezhik
Victor Melezhik
FAR-DEEP Cores 12A/12B
ca. 2050 Ma (Re-Os)
•Conclusions
• Rise of atmospheric oxygen linked to
cratonization, increased proportion of
subaerial volcanism
• Franceville-Onega Excursion (FOE) first
major carbon oxidation event at end of
Lomagundi-Jatuli CIE
• Likely related to oxidative weathering of huge
organic C deposits from LJ-CIE
Topics to cover: • In-situ geochemical analyses of microfossils
• Microbial ecosystems in deep flooded sinkholes (Macalady)
• Large-scale Perturbations of the Paleoproterozoic Carbon Cycle (Kump)
• The Quest for Terrestrial Mass Planets around M dwarfs with Near-Infrared Spectroscopy (Mahadevan)
The Quest for Terrestrial Mass Planets around M dwarfs with Near-Infrared Spectroscopy
www.unige.ch
Simulated Echelle Spectrum, NOAO
PSU: Suvrath Mahadevan, Larry Ramsey,
Ryan Terrien, Stephen Redman, Chad Bender,
Keegan McCoy, Rohit Deshpande, Arpita Roy,
Brandon Botzer, Nate Troupe, Steinn
Sigurdsson
NIST Laser Comb Team: Steve Osterman
(CASA), Gabriel Ycas, Scott Diddams, Frank
Quinlan (NIST)
Why search for planets around M dwarfs?
Most known hosts are ~1 Msun, but ~75% of stars are <0.5 MSun
Spectral class M: M~ .08-.5 Msun T ~ 3000-4000K
Planet Hosts Nearby
stars Stars
Robles et al. (2008)
Why search for planets around M dwarfs? Habitable zone for M dwarf is closer to the small star…
Which means a terrestrial planet in the habitable zone would impart
larger RV signal on star motion…
Where are the
Earths/Super Earths?
Does the planet-
metallicity correlation
extend to lower mass
stars?
However, M dwarfs emit mostly in the infrared,
(where well-developed instruments and techniques cannot be used)
Y+J+H
V
Pavlenko et al. (2007)
Typical M dwarf spectrum
NAI-funded PSU Pathfinder spectrograph:
Testbed spectrograph to explore
challenges in precision NIR RV
Off-the-shelf parts, Uncooled,
Fiber-fed, uses a Hawaii-1 array sensitive to 2.7 microns
Hobby-Eberly Telescope
Leading into a new instrument:
Habitable Zone Planet Finder (HZPF) - NSF MRI – funded!
A fully cooled, high resolution, fiber-fed spectrograph stationed at the Hobby-Ebery
Telescope. RV survey of ~300 M4-M9 stars.
New Hawaii-2 detector in production.
Challenges to working in the NIR
• Thermal Noise
• Modal Noise
• Telluric line
contamination
• Calibration
Wavelength calibration sources for the optical
aren’t as effective in the infrared. Instead, use:
CO2 Telluric Lines
RMS~6m/s
(CRIRES)
Figuera et al. 2010
NH3
RMS~11m/s
(CRIRES)
Bean et al.
2010
Mixtures of
telecom
gases
U/Ar, U/Ne
lamps
Mahadevan & Ge (2009)
The Holy Grail of wavelength calibration sources:
Laser Frequency Combs
www.menlosystems.com
Gilliam et al. (1974)
The first on-sky use of a NIR laser frequency
comb as an RV calibration reference
The first on-sky use of a NIR laser frequency
comb as an RV calibration reference
Calibration 1 (Comb)
Calibration 2 (Comb) Star
Order 37
Order 38
Order 39 {
{
{
Laser frequency comb results:
A Uranium/Neon Map calibrated with a laser
frequency comb
Redman et al. (2011)
Pathfinder NAI-funded test bed instrument for NIR RV
Thermal Blocking
Modal noise
Laser Frequency Comb calibration
Can achieve better than 10 m/s precision!
Ramping up for HZPF
Achieve better than 3 m/s precision!
Find terrestrial Planets in the Habitable Zone
Where are the Earths/Super Earths?
Does the planet-metallicity correlation extend to lower mass stars?
Magical Blue Hole
Archaeal 16S rRNA
50 McCauley, Macalady et al. in prep.
Magical Blue Hole
Bacterial 16S rRNA
McCauley, Macalady et al. in prep.
M dwarfs have plenty of RV information content
Reiners et al. (2010)