News Item
Multidisciplinary Sciences
Alexandra Witze
Summary: The far-seeing observatory has provided significant discoveries from the farthest reaches of the Universe to a moon orbiting Saturn.
News Item
Multidisciplinary Sciences
Alexandra Witze
Summary: Observations from the James Webb Space Telescope indicate that the second planet in a system of seven planets is devoid of an atmosphere.
Article
Astronomy & Astrophysics
Dhvani Doshi, Nicolas B. Cowan, Yi Huang
Summary: The James Webb Space Telescope (JWST) will provide an opportunity to investigate the atmospheres of potentially habitable planets. This study explores the impact of aerosols and clouds on JWST's ability to observe deeper layers of exoplanetary atmospheres. The research finds that JWST would not be able to detect Earth-like stratospheric clouds in the TRAPPIST-1 system, but it would be able to detect them in the habitable zone of a white dwarf after only four transits.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Review
Astronomy & Astrophysics
Robin Wordsworth, Laura Kreidberg
Summary: Rocky planets around other stars are common, but their atmospheric properties are still uncertain. Recent planet discoveries and upcoming advances in observing capability will allow us to characterize the atmospheres of many rocky exoplanets in this decade. Theoretical understanding of rocky exoplanet atmospheres has advanced considerably, providing testable predictions of their evolution, chemistry, dynamics, and possible biosignatures.
ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS
(2022)
Article
Multidisciplinary Sciences
Maggie A. Thompson, Joshua Krissansen-Totton, Nicholas Wogan, Myriam Telus, Jonathan J. Fortney
Summary: Methane has been proposed as a potential biosignature for exoplanets, but it is important to consider the specific planetary conditions. Methane has a short lifetime in terrestrial planet atmospheres and requires large replenishment fluxes. While methane can be produced abiotically, known abiotic processes cannot easily generate atmospheres rich in methane and carbon dioxide with limited carbon monoxide. Therefore, planets with certain conditions are more likely to have biogenic methane.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Astronomy & Astrophysics
Nestor Espinoza, Leonardo Ubeda, Stephan M. M. Birkmann, Pierre Ferruit, Jeff A. A. Valenti, David K. K. Sing, Zafar Rustamkulov, Michael Regan, Sarah Kendrew, Elena Sabbi, Everett Schlawin, Thomas Beatty, Loic Albert, Thomas P. Greene, Nikolay Nikolov, Diane Karakla, Charles Keyes, Catarina Alves de Oliveira, Torsten Boeker, Maria Pena-Guerrero, Giovanna Giardino, Nimisha Kumari, Elena Manjavacas, Charles Proffitt, Timothy Rawle
Summary: We report on the commissioning observations of the exoplanet HAT-P-14 b using the JWST and NIRSpec instrument. The data obtained verify the functionality of NIRSpec BOTS mode and provide a featureless transmission spectrum consistent with atmospheric expectations. The observations showcase the ability of NIRSpec/BOTS to perform cutting-edge atmospheric science for exoplanets, setting the stage for future discoveries in Cycle 1 and beyond.
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC
(2023)
Article
Astronomy & Astrophysics
Rhys Seeburger, Peter M. Higgins, Niall P. Whiteford, Charles S. Cockell
Summary: The viability of detecting methane produced by microbial activity in low-temperature hydrothermal vents on an Archean-Earth-like exoplanet in the habitable zone was explored using a simplified bottom-up approach with a toy model. Simulations of methanogens at hydrothermal vent sites in the deep ocean were used to determine biological methane production rates. These production rates were then used to estimate likely methane concentrations in the simplified atmosphere.
Article
Astronomy & Astrophysics
Klaus M. Pontoppidan, Jaclyn Barrientes, Claire Blome, Hannah Braun, Matthew Brown, Margaret Carruthers, Dan Coe, Joseph DePasquale, Nestor Espinoza, Macarena Garcia Marin, Karl D. Gordon, Alaina Henry, Leah Hustak, Andi James, Ann Jenkins, Anton M. Koekemoer, Stephanie LaMassa, David Law, Alexandra Lockwood, Amaya Moro-Martin, Susan E. Mullally, Alyssa Pagan, Dani Player, Charles Proffitt, Christine Pulliam, Leah Ramsay, Swara Ravindranath, Neill Reid, Massimo Robberto, Elena Sabbi, Leonardo Ubeda, Michael Balogh, Kathryn Flanagan, Jonathan Gardner, Hashima Hasan, Bonnie Meinke, Antonella Nota
Summary: The James Webb Space Telescope Early Release Observations are a set of public outreach products that demonstrate the readiness and capability of JWST for scientific research.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Multidisciplinary Sciences
Z. Rustamkulov, D. K. Sing, S. Mukherjee, E. M. May, J. Kirk, E. Schlawin, M. R. Line, C. Piaulet, A. L. Carter, N. E. Batalha, J. M. Goyal, M. Lopez-Morales, J. D. Lothringer, R. J. MacDonald, S. E. Moran, K. B. Stevenson, H. R. Wakeford, N. Espinoza, J. L. Bean, N. M. Batalha, B. Benneke, Z. K. Berta-Thompson, I. J. M. Crossfield, P. Gao, L. Kreidberg, D. K. Powell, P. E. Cubillos, N. P. Gibson, J. Leconte, K. Molaverdikhani, N. K. Nikolov, V. Parmentier, P. Roy, J. Taylor, J. D. Turner, P. J. Wheatley, K. Aggarwal, E. Ahrer, M. K. Alam, L. Alderson, N. H. Allen, A. Banerjee, S. Barat, D. Barrado, J. K. Barstow, T. J. Bell, J. Blecic, J. Brande, S. Casewell, Q. Changeat, K. L. Chubb, N. Crouzet, T. Daylan, L. Decin, J. Desert, T. Mikal-Evans, A. D. Feinstein, L. Flagg, J. J. Fortney, J. Harrington, K. Heng, Y. Hong, R. Hu, N. Iro, T. Kataria, E. m. -r. Kempton, J. Krick, M. Lendl, J. Lillo-Box, A. Louca, J. Lustig-Yaeger, L. Mancini, M. Mansfield, N. J. Mayne, Y. Miguel, G. Morello, K. Ohno, E. Palle, D. J. M. Petit Dit de la Roche, B. V. Rackham, M. Radica, L. Ramos-Rosado, S. Redfield, L. K. Rogers, E. L. Shkolnik, J. Southworth, J. Teske, P. Tremblin, G. S. Tucker, O. Venot, W. C. Waalkes, L. Welbanks, X. Zhang, S. Zieba
Summary: We measured a broad-wavelength 0.5-5.5 μm atmospheric transmission spectrum of the exoplanet WASP-39b using JWST NIRSpec's PRISM mode. We detected several chemical species, including Na, H2O, CO2, and CO, with high significance. The non-detection of CH4 and the presence of a strong CO2 feature favor atmospheric models with a super-solar atmospheric metallicity. The unexpected absorption feature at 4 μm is best explained by SO2, which could be a tracer of atmospheric photochemistry. These observations demonstrate the sensitivity of JWST to diverse exoplanet compositions and chemical processes.
Article
Astronomy & Astrophysics
Jessica J. Spake, A. Oklopcic, L. A. Hillenbrand, Heather A. Knutson, David Kasper, Fei Dai, Jaume Orell-Miquel, Shreyas Vissapragada, Michael Zhang, Jacob L. Bean
Summary: Observations of helium in exoplanet atmospheres can provide insights into atmospheric escape and contamination. This study used two different instruments to observe the helium absorption in GJ 1214b and found discrepancies in the results. The discrepancies may be caused by contamination from telluric lines or correlated noise in the observations. The underlying cause of the differences, whether it is correlated noise or variability in the planetary atmosphere, remains unclear.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Astronomy & Astrophysics
M. Malin, A. Boccaletti, B. Charnay, F. Kiefer, B. Bezard
Summary: This article explores the detection and characterization of molecules in the atmosphere of exoplanets using the recently launched James Webb Space Telescope's Medium Resolution Spectrometer. It is found that the MIRI/MRS can detect directly imaged planets and various molecular features (such as H2O, CO, NH3, CH4, HCN, PH3, CO2) at different strengths. This study is important for characterizing future detected planets.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Shang-Min Tsai, Hamish Innes, Tim Lichtenberg, Jake Taylor, Matej Malik, Katy Chubb, Raymond Pierrehumbert
Summary: The majority of discovered exoplanets are smaller than Neptune and larger than Earth, with H-2-rich atmospheres being prime targets for atmospheric characterization. Trace gases like ammonia and hydrogen cyanide are proposed proxies for the presence of a shallow surface on sub-Neptunes. Methanol is identified as another complementary proxy for surface characteristics.
ASTROPHYSICAL JOURNAL LETTERS
(2021)
Article
Geochemistry & Geophysics
Laura K. Schaefer, Vivien Parmentier
Summary: The atmospheric composition of rocky exoplanets is influenced by their bulk composition and orbital position. While hot planets may have nontraditional gases, clement planets depend on volatile richness acquired during planet formation. Future observatories will enhance precision in probing exoplanet atmospheres, presenting new challenges for terrestrial planet observations.
Article
Astronomy & Astrophysics
Jeroen Bouwman, Sarah Kendrew, Thomas P. Greene, Taylor J. Bell, Pierre-Olivier Lagage, Juergen Schreiber, Daniel Dicken, G. C. Sloan, Nestor Espinoza, Silvia Scheithauer, Alain Coulais, Ori D. Fox, Rene Gastaud, Adrian M. Glauser, Olivia C. Jones, Alvaro Labiano, Fred Lahuis, Jane E. Morrison, Katherine Murray, Michael Mueller, Omnarayani Nayak, Gillian S. Wright, Alistair Glasse, George Rieke
Summary: In this study, we conducted the first mid-infrared spectroscopic time series observation of the transiting exoplanet L 168-9 b using the Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope. The performance of the Low Resolution Spectroscopy (LRS) mode for challenging observations was characterized by two independent analyses of the data. Our results demonstrate the potential of MIRI for characterizing exoplanet atmospheres.
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC
(2023)
Article
Astronomy & Astrophysics
Edwin S. Kite, Laura Schaefer
Summary: Most hot rocky exoplanets are believed to have evolved from gas-rich sub-Neptunes by losing most of their envelopes, with uncertainty about whether they retain atmospheres. New research suggests that rocky exoplanets with diameters of 1-1.7 Earth radii and masses of 1-10 Earth masses can acquire long-lived, H2O-dominated atmospheres with pressures of 10-2000 bar during their evolution. The presence of these atmospheres is thought to be a common outcome of interactions between nebula-derived atmospheres and oxidized magma, and can be tested with the James Webb Space Telescope.
ASTROPHYSICAL JOURNAL LETTERS
(2021)
Article
Astronomy & Astrophysics
Jingcheng Huang, Sara Seager, Janusz J. Petkowski, Sukrit Ranjan, Zhuchang Zhan
Summary: Ammonia is a good biosignature gas, but its accumulation in a planetary atmosphere requires strict conditions. A smaller biological production is needed for detectability when the surface is saturated with ammonia, but a significantly higher production is required when the surface is unsaturated. Additionally, volatile amines share similar properties with ammonia and can also serve as biosignature gases.
Article
Chemistry, Inorganic & Nuclear
William Bains, Janusz J. Petkowski, Sara Seager, Sukrit Ranjan, Clara Sousa-Silva, Paul B. Rimmer, Zhuchang Zhan, Jane S. Greaves, Anita M. S. Richards
Summary: The potential detection of ppb levels phosphine (PH3) in the clouds of Venus through millimeter-wavelength astronomical observations challenges the consensus model and suggests an unknown geo- or photochemistry process. It may imply that the understanding of Venus' chemistry is significantly incomplete, or even that a strictly aerial microbial biosphere could produce PH3.
PHOSPHORUS SULFUR AND SILICON AND THE RELATED ELEMENTS
(2022)
Letter
Multidisciplinary Sciences
William Bains, Oliver Shorttle, Sukrit Ranjan, Paul B. Rimmer, Janusz J. Petkowski, Jane S. Greaves, Sara Seager
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Astronomy & Astrophysics
William Bains, Oliver Shorttle, Sukrit Ranjan, Paul B. Rimmer, Janusz J. Petkowski, Jane S. Greaves, Sara Seager
Summary: Research suggests that the presence of phosphine in the cloud decks of Venus may be linked to volcanic activity, although the eruption of phosphides from deep mantle to explain the observed phosphine levels is unlikely. A significant volume of eruption would be required to account for the presence of phosphine in the clouds, exceeding any historical terrestrial eruption rates.
Article
Nanoscience & Nanotechnology
Monika U. Weber, Janusz J. Petkowski, Robert E. Weber, Bartosz Krajnik, Slawomir Stemplewski, Marta Panek, Tomasz Dziubak, Paulina Mrozinska, Anna Piela, Emil Paluch
Summary: We experimentally validated the theoretical design constraints of the ring electrode architecture and compared its performance with the dot electrode structure. The ring structure achieved 99% efficiency in bacterial capture and showed a significantly faster response to the electric field. We also identified critical design constraints for high efficiency bacterial capture.
Article
Nanoscience & Nanotechnology
Monika U. Weber, Janusz J. Petkowski, Robert E. Weber, Bartosz Krajnik, Slawomir Stemplewski, Marta Panek, Tomasz Dziubak, Paulina Mrozinska, Anna Piela, Siu Lung Lo, Hazael F. Montanaro Ochoa, Christopher D. Yerino
Summary: We model the dielectrophoretic response of E. coli bacterial cells and red blood cells to an electric field and investigate the efficient separation of different cell types in a microfluidic channel. The modelling work guides the design of separation electrode architecture for experimental validation. Our simulations show that designing the electrode structure with periodicity ensures efficient capture and separation, and the system outperforms circular electrode architectures in terms of capture and separation efficiency. The modelled microfluidic design allows for the subsequent detection of separated bacteria using label-free functionalized nanowire sensors.
Article
Astronomy & Astrophysics
William Bains, Janusz J. Petkowski, Sara Seager
Summary: Despite the inhospitable conditions on Venus for Earth life, it is still possible that life exists based on our understanding of the principles of life on Earth. There is sufficient energy, manageable energy requirements for water retention and biomass formation, conceivable defenses against sulfuric acid, and the speculative possibility of using concentrated sulfuric acid as a solvent. Limited availability of metals and a benign radiation environment further support the potential for life. Detecting life in the Venusian atmosphere through future astrobiology-focused space missions is a justifiable scientific endeavor.
Article
Multidisciplinary Sciences
Sara Seager, Janusz J. Petkowski, Maxwell D. Seager, John H. Grimes Jr, Zachary Zinsli, Heidi R. Vollmer-Snarr, Mohamed K. Abd El-Rahman, David S. Wishart, Brian L. Lee, Vasuk Gautam, Lauren Herrington, William Bains, Charles Darrow
Summary: The habitability of planets requires exploration beyond our Earth-centric viewpoint. Venus' clouds, composed of concentrated sulfuric acid, were previously thought to be incapable of supporting life. However, recent research demonstrates that key molecules needed for life, such as nucleic acid bases, can be stable in this environment. This finding advances the possibility that the Venus atmosphere may be able to support complex chemicals necessary for life.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Multidisciplinary
William Bains, Matthew A. Pasek, Sukrit Ranjan, Janusz J. Petkowski, Arthur Omran, Sara Seager
Summary: The formation of phosphine from P4O6 in the Venusian atmosphere is thermodynamically unfavorable, indicating a need for more robust data to understand the atmospheres of Venus and gas giant planets.
ACS EARTH AND SPACE CHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Sara Seager, Janusz J. Petkowski, Jingcheng Huang, Zhuchang Zhan, Sai Ravela, William Bains
Summary: We propose nitrogen trifluoride (NF3) and sulfur hexafluoride (SF6) as ideal technosignature gases due to their special industrial properties, lack of presence in Earth's pre-industrial atmosphere, unique spectral features, and long atmospheric lifetimes.
SCIENTIFIC REPORTS
(2023)
Article
Engineering, Aerospace
Richard French, Christophe Mandy, Richard Hunter, Ehson Mosleh, Doug Sinclair, Peter Beck, Sara Seager, Janusz J. Petkowski, Christopher E. Carr, David H. Grinspoon, Darrel Baumgardner
Summary: Regular, low-cost Decadal-class science missions to planets will be made possible by high-Delta V small spacecraft and small launch vehicles, increasing opportunities for scientists and the rate of science return. Rocket Lab plans to launch a small direct entry probe to Venus in 2023 to collect data on the planet's cloud layers. The probe will spend about 5 minutes in the Venus clouds collecting measurements of organic molecules and particle composition.
Article
Engineering, Aerospace
Weston P. Buchanan, Maxim de Jong, Rachana Agrawal, Janusz J. Petkowski, Archit Arora, Sarag J. Saikia, Sara Seager, James Longuski
Summary: The mounting evidence of chemical disequilibria in the Venusian atmosphere has increased the interest in searching for life within the planet's cloud decks. Balloon systems are considered to be the best aerial platform for extended atmospheric sampling in the clouds, providing high science return to risk ratio. This study presents options for constant- and variable-altitude balloon systems designed to perform science operations inside the Venusian cloud decks.
Article
Engineering, Aerospace
Sara Seager, Janusz J. Petkowski, Christopher E. Carr, David H. Grinspoon, Bethany L. Ehlmann, Sarag J. Saikia, Rachana Agrawal, Weston P. Buchanan, Monika U. Weber, Richard French, Pete Klupar, Simon P. Worden, Darrel Baumgardner
Summary: The Venus Life Finder (VLF) missions aim to assess the habitability of the Venusian clouds and search for signs of extraterrestrial life. The project, led by MIT, is focused on astrobiology and can be launched quickly and at a relatively low cost.
Article
Engineering, Aerospace
Rachana Agrawal, Weston P. Buchanan, Archit Arora, Athul P. Girija, Maxim De Jong, Sara Seager, Janusz J. Petkowski, Sarag J. Saikia, Christopher E. Carr, David H. Grinspoon, James M. Longuski
Summary: This article introduces a mission concept to explore the clouds of Venus in order to evaluate habitability and search for signs of life. A super-pressure variable float altitude balloon aerobot is proposed to cycle between different cloud layers and transmit data through an orbiter relay. The mission, scheduled for 2026, aims to complement other planned missions and shed light on the limits of habitability and the role of unknown chemistry or possibly life itself in the Venus atmosphere.
Article
Computer Science, Information Systems
William Bains, Janusz Jurand Petkowski, Zhuchang Zhan, Sara Seager
Summary: The thermodynamic properties of a substance are crucial for predicting its behavior in physical and chemical systems. By collecting experimental data and developing models, the values of enthalpy of formation and entropy can be predicted, allowing us to determine whether reactions will proceed spontaneously under specific conditions and the heat and work yield of those reactions. This is valuable for predicting processes involving the generation or destruction of volatile products, and also provides reference for others developing predictive models.