Journal articles: 'Trappists'

1

Leach, Amy. "The Trappists." Iowa Review 36, no. 1 (April 2006): 55. http://dx.doi.org/10.17077/0021-065x.6167.

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Maltagliati, Luca. "Clouds over TRAPPISTs." Nature Astronomy 3, no. 1 (December 18, 2018): 14. http://dx.doi.org/10.1038/s41550-018-0679-6.

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Khandlhela, Risimati Sam. "The Trappists in South Africa: a short overview." Kleio 27, no. 1 (January 1995): 46–62. http://dx.doi.org/10.1080/00232089585310041.

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Delpal, Bernard. "Travail, loisir et observance chez les trappistes au XIXe siècle / Work, Leisure and Observance among Trappists during the XIXth Century." Archives de sciences sociales des religions 86, no. 1 (1994): 213–33. http://dx.doi.org/10.3406/assr.1994.1440.

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5

Butler, Jay. "Agricultural Missionaries: The Trappists and French Colonial Policy under the July Monarchy." Catholic Historical Review 106, no. 2 (2020): 256–81. http://dx.doi.org/10.1353/cat.2020.0041.

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6

Balbo, Ned, and Richard Howard. "Trappings." Antioch Review 58, no. 3 (2000): 380. http://dx.doi.org/10.2307/4614044.

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Tan, Jin, and Ming-Fen Li. "Rapid and nondestructive identification of Belgian and Netherlandish Trappist beers by front-face synchronous fluorescence spectroscopy coupled with multiple statistical analysis." Quality Assurance and Safety of Crops & Foods 13, no. 1 (February 7, 2021): 83–92. http://dx.doi.org/10.15586/qas.v13i1.839.

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Front-face synchronous fluorescence spectroscopy (FFSFS) was applied for the rapid and noninvasive recognition of Belgian and Netherlandish Trappist beers against non-Trappist beers. The front-face synchronous fluorescence spectra at wavelength intervals (??) of 30 and 60 nm for 80 bottles of beer, including 41 Trappist and 39 non-Trap-pist beers, were acquired in a 5 × 10 mm fused-quartz cuvette settled in a traditional right-angle sample compartment. The discrimination model was constructed by either principal component analysis (PCA) combined with linear discriminant analysis (LDA) or partial least squares-discriminant analysis (PLS-DA). Both PCA–LDA and PLS-DA models were validated by full (leave-one-out) cross-validation and k-fold cross-validation (k = 5). The PCA–LDA model presents reliable discrimination performance, with the cross-validated sensitivity (true positive rate) and specificity (true negative rate) in the range of 82.9–85.4% and 71.8–76.9%, respectively. The misclassification mainly occurs to a small portion of ambiguous Trappist and non-Trappist samples such as Abbey beers, which are rather similar to Trappist beers.

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Maciel, Samara Rebeka Pita, and Jean Paulo dos Santos Carvalho. "Evolução Orbital dos Exoplanetas (TRAPPIST-1e e TRAPPIST-1g) que estão na Zona Habitável da Estrela TRAPPIST-1." Sitientibus Série Ciências Físicas 16 (December 30, 2020): 1. http://dx.doi.org/10.13102/sscf.v16i0.6010.

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A abordagem central baseia-se no problema de três corpos, em que é analisada a dinâmica secular de um sistema composto por uma estrela central e dois planetas sob influência gravitacional mútua, considerando a perturbação devido ao efeito da atração gravitacional do terceiro corpo em órbita elíptica e inclinada até a terceira ordem do potencial perturbador. Apresentamos uma análise da evolução orbital dos exoplanetas que estão na zona habitável da estrela. O software Maple é usado para fazer as integrações numéricas, outro software também utilizado é o Universe Sandbox para comparar o resultado obtido das integrações das equações analíticas devido a perturbação do terceiro corpo. Mostramos que os exoplanetas (TRAPPIST-1e e TRAPPIST-1g) que estão na zona habitável da estrela TRAPPIST-1 permanecem dentro da zonal habitável ao longo do tempo.

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Maciel, Samara Rebeka Pita, and Jean Paulo dos Santos Carvalho. "Evolução Orbital dos Exoplanetas (TRAPPIST-1e e TRAPPIST-1g) que estão na Zona Habitável da Estrela TRAPPIST-1." Sitientibus Série Ciências Físicas 16 (December 30, 2020): 1–13. http://dx.doi.org/10.13102/sscf.v16i.6010.

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A abordagem central baseia-se no problema de três corpos, em que é analisada a dinâmica secular de um sistema composto por uma estrela central e dois planetas sob influência gravitacional mútua, considerando a perturbação devido ao efeito da atração gravitacional do terceiro corpo em órbita elíptica e inclinada até a terceira ordem do potencial perturbador. Apresentamos uma análise da evolução orbital dos exoplanetas que estão na zona habitável da estrela. O software Maple é usado para fazer as integrações numéricas, outro software também utilizado é o Universe Sandbox para comparar o resultado obtido das integrações das equações analíticas devido a perturbação do terceiro corpo. Mostramos que os exoplanetas (TRAPPIST-1e e TRAPPIST-1g) que estão na zona habitável da estrela TRAPPIST-1 permanecem dentro da zonal habitável ao longo do tempo.

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Lienhard, F., D. Queloz, M. Gillon, A. Burdanov, L. Delrez, E. Ducrot, W. Handley, et al. "Global analysis of the TRAPPIST Ultra-Cool Dwarf Transit Survey." Monthly Notices of the Royal Astronomical Society 497, no. 3 (July 15, 2020): 3790–808. http://dx.doi.org/10.1093/mnras/staa2054.

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ABSTRACT We conducted a global analysis of the TRAPPIST Ultra-Cool Dwarf Transit Survey – a prototype of the SPECULOOS transit search conducted with the TRAPPIST-South robotic telescope in Chile from 2011 to 2017 – to estimate the occurrence rate of close-in planets such as TRAPPIST-1b orbiting ultra-cool dwarfs. For this purpose, the photometric data of 40 nearby ultra-cool dwarfs were reanalysed in a self-consistent and fully automated manner starting from the raw images. The pipeline developed specifically for this task generates differential light curves, removes non-planetary photometric features and stellar variability, and searches for transits. It identifies the transits of TRAPPIST-1b and TRAPPIST-1c without any human intervention. To test the pipeline and the potential output of similar surveys, we injected planetary transits into the light curves on a star-by-star basis and tested whether the pipeline is able to detect them. The achieved photometric precision enables us to identify Earth-sized planets orbiting ultra-cool dwarfs as validated by the injection tests. Our planet-injection simulation further suggests a lower limit of 10 per cent on the occurrence rate of planets similar to TRAPPIST-1b with a radius between 1 and 1.3 R⊕ and the orbital period between 1.4 and 1.8 d.

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Hochman, Assaf, Paolo De Luca, and Thaddeus D. Komacek. "Greater Climate Sensitivity and Variability on TRAPPIST-1e than Earth." Astrophysical Journal 938, no. 2 (October 1, 2022): 114. http://dx.doi.org/10.3847/1538-4357/ac866f.

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Abstract The atmospheres of rocky exoplanets are close to being characterized by astronomical observations, in part due to the commissioning of the JWST. These observations compel us to understand exoplanetary atmospheres, in the voyage to find habitable planets. With this aim, we investigate the effect that CO2 partial pressure (pCO2) has on exoplanets’ climate variability, by analyzing results from ExoCAM model simulations of the tidally locked TRAPPIST-1e exoplanet, an Earth-like aqua-planet, and Earth itself. First, we relate the differences between the planets to their elementary parameters. Then, we compare the sensitivity of the Earth analog and TRAPPIST-1e’s surface temperature and precipitation to pCO2. Our simulations suggest that the climatology and extremes of TRAPPIST-1e’s temperature are ∼1.5 times more sensitive to pCO2 relative to Earth. The precipitation sensitivity strongly depends on the specific region analyzed. Indeed, the precipitation near mid-latitude and equatorial substellar regions of TRAPPIST-1e is more sensitive to pCO2, and the precipitation sensitivity is ∼2 times larger in TRAPPIST-1e. A dynamical systems perspective, which provides information about how the atmosphere evolves in phase space, provides additional insights. Notably, an increase in pCO2 results in an increase in atmospheric persistence on both planets, and the persistence of TRAPPIST-1e is more sensitive to pCO2 than Earth. We conclude that the climate of TRAPPIST-1e may be more sensitive to pCO2, particularly on its dayside. This study documents a new pathway for understanding the effect that varying planetary parameters have on the climate variability of potentially habitable exoplanets and on Earth.

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Bansal, Dhananjhay, Hannah S. Christie, and Mathieu Dumberry. "Libration- and Precession-driven Dissipation in the Fluid Cores of the TRAPPIST-1 Planets." Planetary Science Journal 4, no. 9 (September 1, 2023): 171. http://dx.doi.org/10.3847/psj/acf3de.

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Abstract The seven planets orbiting TRAPPIST-1 have sizes and masses similar to Earth and mean densities that suggest that their interior structures are comprised of a fluid iron core and rocky mantle. Here we use idealized analytical models to compute estimates of the viscous dissipation in the fluid cores of the TRAPPIST-1 planets induced by mantle libration and precession. The dissipation induced by the libration at orbital periods is largest for TRAPPIST-1b, of the order of 600 MW, and decreases with orbital distance, to values of 5–500 W for TRAPPIST-1h, depending on its triaxial shape. Extrapolating these results to the larger libration amplitudes expected at longer periods, dissipation may perhaps be as high as 1 TW in TRAPPIST-1b. Orbital precession induces a misalignment between the spin axes of the fluid core and mantle of a planet, the amplitude of which depends on the resonant amplification of its free precession and free core nutation. Assuming Cassini states, we show that the dissipation from this misalignment can reach a few TW for planets e and f. Our dissipation estimates are lower bounds, as we neglect ohmic dissipation, which may dominate if the fluid cores of the TRAPPIST-1 planets sustain magnetic fields. Our results suggest that dissipation induced by precession can be of the same order as tidal dissipation for the outermost planets, may perhaps be sufficient to supply the power to a generate a magnetic field in their liquid cores, and likely played an important role in the evolution of the TRAPPIST-1 system.

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Teixeira, Katie E., Caroline V. Morley, Bradford J. Foley, and Cayman T. Unterborn. "The Carbon-deficient Evolution of TRAPPIST-1c." Astrophysical Journal 960, no. 1 (December 21, 2023): 44. http://dx.doi.org/10.3847/1538-4357/ad0cec.

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Abstract Transiting planets orbiting M dwarfs provide the best opportunity to study the atmospheres of rocky planets with current facilities. As JWST enters its second year of science operations, an important initial endeavor is to determine whether these rocky planets have atmospheres at all. M dwarfs are thought to pose a major threat to planetary atmospheres due to their high magnetic activity over timescales of several billion years, and might completely strip atmospheres. Several Cycle 1 and 2 General Observers and Guaranteed Time Observations programs are testing this hypothesis, observing a series of rocky planets to determine whether they retained their atmospheres. A key case study is TRAPPIST-1c, which receives almost the same bolometric flux as Venus. We might therefore expect TRAPPIST-1c to possess a thick, CO2-dominated atmosphere. Instead, Zieba et al. show that it has little to no CO2 in its atmosphere. To interpret these results, we run coupled time-dependent simulations of planetary outgassing and atmospheric escape to model the evolution of TRAPPIST-1c's atmosphere. We find that the stellar wind stripping that is expected to occur on TRAPPIST-1c over its lifetime can only remove up to ∼16 bar of CO2, less than the modern CO2 inventory of either Earth or Venus. Therefore, we infer that TRAPPIST-1c either formed volatile-poor, as compared to Earth and Venus, or lost a substantial amount of CO2 during an early phase of hydrodynamic hydrogen escape. Finally, we scale our results for the other TRAPPIST-1 planets, finding that the more distant TRAPPIST-1 planets may readily retain atmospheres.

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Turbet, Martin, Emeline Bolmont, Jeremy Leconte, François Forget, Franck Selsis, Gabriel Tobie, Anthony Caldas, Joseph Naar, and Michaël Gillon. "Modeling climate diversity, tidal dynamics and the fate of volatiles on TRAPPIST-1 planets." Astronomy & Astrophysics 612 (April 2018): A86. http://dx.doi.org/10.1051/0004-6361/201731620.

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TRAPPIST-1 planets are invaluable for the study of comparative planetary science outside our solar system and possibly habitability. Both transit timing variations (TTV) of the planets and the compact, resonant architecture of the system suggest that TRAPPIST-1 planets could be endowed with various volatiles today. First, we derived from N-body simulations possible planetary evolution scenarios, and show that all the planets are likely in synchronous rotation. We then used a versatile 3D global climate model (GCM) to explore the possible climates of cool planets around cool stars, with a focus on the TRAPPIST-1 system. We investigated the conditions required for cool planets to prevent possible volatile species to be lost permanently by surface condensation, irreversible burying or photochemical destruction. We also explored the resilience of the same volatiles (when in condensed phase) to a runaway greenhouse process. We find that background atmospheres made of N2, CO, or O2are rather resistant to atmospheric collapse. However, even if TRAPPIST-1 planets were able to sustain a thick background atmosphere by surviving early X/EUV radiation and stellar wind atmospheric erosion, it is difficult for them to accumulate significant greenhouse gases like CO2, CH4, or NH3. CO2can easily condense on the permanent nightside, forming CO2ice glaciers that would flow toward the substellar region. A complete CO2ice surface cover is theoretically possible on TRAPPIST-1g and h only, but CO2ices should be gravitationally unstable and get buried beneath the water ice shell in geologically short timescales. Given TRAPPIST-1 planets large EUV irradiation (at least ~103 × Titan’s flux), CH4and NH3are photodissociated rapidly and are thus hard to accumulate in the atmosphere. Photochemical hazes could then sedimentate and form a surface layer of tholins that would progressively thicken over the age of the TRAPPIST-1 system. Regarding habitability, we confirm that few bars of CO2would suffice to warm the surface of TRAPPIST-1f and g above the melting point of water. We also show that TRAPPIST-1e is a remarkable candidate for surface habitability. If the planet is today synchronous and abundant in water, then it should very likely sustain surface liquid water at least in the substellar region, whatever the atmosphere considered.

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15

LIGO, Vivian. "The Trappist Monk Revisited." Louvain Studies 16, no. 4 (December 1, 1991): 312–30. http://dx.doi.org/10.2143/ls.16.4.2013815.

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16

Bolmont, E., B. O. Demory, S. Blanco-Cuaresma, E. Agol, S. L. Grimm, P. Auclair-Desrotour, F. Selsis, and A. Leleu. "Impact of tides on the transit-timing fits to the TRAPPIST-1 system." Astronomy & Astrophysics 635 (March 2020): A117. http://dx.doi.org/10.1051/0004-6361/202037546.

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Transit timing variations (TTVs) can be a very efficient way of constraining masses and eccentricities of multi-planet systems. Recent measurements of the TTVs of TRAPPIST-1 have led to an estimate of the masses of the planets, enabling an estimate of their densities and their water content. A recent TTV analysis using data obtained in the past two years yields a 34 and 13% increase in mass for TRAPPIST-1b and c, respectively. In most studies to date, a Newtonian N-body model is used to fit the masses of the planets, while sometimes general relativity is accounted for. Using the Posidonius N-body code, in this paper we show that in the case of the TRAPPIST-1 system, non-Newtonian effects might also be relevant to correctly model the dynamics of the system and the resulting TTVs. In particular, using standard values of the tidal Love number k2 (accounting for the tidal deformation) and the fluid Love number k2f (accounting for the rotational flattening) leads to differences in the TTVs of TRAPPIST-1b and c that are similar to the differences caused by general relativity. We also show that relaxing the values of tidal Love number k2 and the fluid Love number k2f can lead to TTVs which differ by as much as a few 10 s on a 3−4-yr timescale, which is a potentially observable level. The high values of the Love numbers needed to reach observable levels for the TTVs could be achieved for planets with a liquid ocean, which if detected might then be interpreted as a sign that TRAPPIST-1b and TRAPPIST-1c could have a liquid magma ocean. For TRAPPIST-1 and similar systems the models to fit the TTVs should potentially account for general relativity, for the tidal deformation of the planets, for the rotational deformation of the planets, and to a lesser extent for the rotational deformation of the star, which would add up to 7 × 2 + 1 = 15 additional free parameters in the case of TRAPPIST-1.

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17

Klopper, Abigail. "Gold trappings." Nature Physics 14, no. 7 (July 2018): 636. http://dx.doi.org/10.1038/s41567-018-0220-y.

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Grimm, Simon L., Brice-Olivier Demory, Michaël Gillon, Caroline Dorn, Eric Agol, Artem Burdanov, Laetitia Delrez, et al. "The nature of the TRAPPIST-1 exoplanets." Astronomy & Astrophysics 613 (May 2018): A68. http://dx.doi.org/10.1051/0004-6361/201732233.

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Context. The TRAPPIST-1 system hosts seven Earth-sized, temperate exoplanets orbiting an ultra-cool dwarf star. As such, it represents a remarkable setting to study the formation and evolution of terrestrial planets that formed in the same protoplanetary disk. While the sizes of the TRAPPIST-1 planets are all known to better than 5% precision, their densities have significant uncertainties (between 28% and 95%) because of poor constraints on the planet’s masses. Aims. The goal of this paper is to improve our knowledge of the TRAPPIST-1 planetary masses and densities using transit-timing variations (TTVs). The complexity of the TTV inversion problem is known to be particularly acute in multi-planetary systems (convergence issues, degeneracies and size of the parameter space), especially for resonant chain systems such as TRAPPIST-1. Methods. To overcome these challenges, we have used a novel method that employs a genetic algorithm coupled to a full N-body integrator that we applied to a set of 284 individual transit timings. This approach enables us to efficiently explore the parameter space and to derive reliable masses and densities from TTVs for all seven planets. Results. Our new masses result in a five- to eight-fold improvement on the planetary density uncertainties, with precisions ranging from 5% to 12%. These updated values provide new insights into the bulk structure of the TRAPPIST-1 planets. We find that TRAPPIST-1 c and e likely have largely rocky interiors, while planets b, d, f, g, and h require envelopes of volatiles in the form of thick atmospheres, oceans, or ice, in most cases with water mass fractions less than 5%.

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Lim, Olivia, Björn Benneke, René Doyon, Ryan J. MacDonald, Caroline Piaulet, Étienne Artigau, Louis-Philippe Coulombe, et al. "Atmospheric Reconnaissance of TRAPPIST-1 b with JWST/NIRISS: Evidence for Strong Stellar Contamination in the Transmission Spectra." Astrophysical Journal Letters 955, no. 1 (September 1, 2023): L22. http://dx.doi.org/10.3847/2041-8213/acf7c4.

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Abstract TRAPPIST-1 is a nearby system of seven Earth-sized, temperate, rocky exoplanets transiting a Jupiter-sized M8.5V star, ideally suited for in-depth atmospheric studies. Each TRAPPIST-1 planet has been observed in transmission both from space and from the ground, confidently rejecting cloud-free, hydrogen-rich atmospheres. Secondary eclipse observations of TRAPPIST-1 b with JWST/MIRI are consistent with little to no atmosphere given the lack of heat redistribution. Here we present the first transmission spectra of TRAPPIST-1 b obtained with JWST/NIRISS over two visits. The two transmission spectra show moderate to strong evidence of contamination from unocculted stellar heterogeneities, which dominates the signal in both visits. The transmission spectrum of the first visit is consistent with unocculted starspots and the second visit exhibits signatures of unocculted faculae. Fitting the stellar contamination and planetary atmosphere either sequentially or simultaneously, we confirm the absence of cloud-free, hydrogen-rich atmospheres, but cannot assess the presence of secondary atmospheres. We find that the uncertainties associated with the lack of stellar model fidelity are one order of magnitude above the observation precision of 89 ppm (combining the two visits). Without affecting the conclusion regarding the atmosphere of TRAPPIST-1 b, this highlights an important caveat for future explorations, which calls for additional observations to characterize stellar heterogeneities empirically and/or theoretical works to improve model fidelity for such cool stars. This need is all the more justified as stellar contamination can affect the search for atmospheres around the outer, cooler TRAPPIST-1 planets for which transmission spectroscopy is currently the most efficient technique.

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Krissansen-Totton, Joshua. "Implications of Atmospheric Nondetections for Trappist-1 Inner Planets on Atmospheric Retention Prospects for Outer Planets." Astrophysical Journal Letters 951, no. 2 (July 1, 2023): L39. http://dx.doi.org/10.3847/2041-8213/acdc26.

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Abstract JWST secondary eclipse observations of Trappist-1b seemingly disfavor atmospheres >∼1 bar since heat redistribution is expected to yield dayside emission temperature below the ∼500 K observed. Given the similar densities of Trappist-1 planets, and the theoretical potential for atmospheric erosion around late M dwarfs, this observation might be assumed to imply substantial atmospheres are also unlikely for the outer planets. However, the processes governing atmosphere erosion and replenishment are fundamentally different for inner and outer planets. Here, an atmosphere–interior evolution model is used to show that an airless Trappist-1b (and c) only weakly constrains stellar evolution, and that the odds of outer planets e and f retaining substantial atmospheres remain largely unchanged. This is true even if the initial volatile inventories of planets in the Trappist-1 system are highly correlated. The reason for this result is that b and c sit unambiguously interior to the runaway greenhouse limit, and so have potentially experienced ∼8 Gyr of X-ray and extreme ultraviolet–driven hydrodynamic escape; complete atmospheric erosion in this environment only weakly constrains stellar evolution and escape parameterizations. In contrast, e and f reside within the habitable zone, and likely experienced a comparatively short steam atmosphere during Trappist-1's pre-main sequence, and consequently complete atmospheric erosion remains unlikely across a broad swath of parameter space (e and f retain atmospheres in ∼98% of model runs). Naturally, it is still possible that all Trappist-1 planets formed volatile-poor and are all airless today. But the airlessness of b (and c) does not require this, and as such, JWST transit spectroscopy of e and f remains the best near-term opportunity to characterize the atmospheres of habitable zone terrestrial planets.

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Grootel, Valérie Van, Catarina S. Fernandes, Michael Gillon, Emmanuel Jehin, Jean Manfroid, Richard Scuflaire, Adam J. Burgasser, et al. "Stellar Parameters for Trappist-1." Astrophysical Journal 853, no. 1 (January 19, 2018): 30. http://dx.doi.org/10.3847/1538-4357/aaa023.

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Dmitrienko, E. S., and I. S. Savanov. "Activity of TRAPPIST-1 Analogs." Astronomy Letters 48, no. 11 (November 2022): 676–81. http://dx.doi.org/10.1134/s1063773722110068.

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Hammond, Tobi, and Thaddeus D. Komacek. "The Coupled Impacts of Atmospheric Composition and Obliquity on the Climate Dynamics of TRAPPIST-1e." Astrophysical Journal 968, no. 1 (June 1, 2024): 43. http://dx.doi.org/10.3847/1538-4357/ad4a59.

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Abstract Planets in multiplanet systems are expected to migrate inward as near-resonant chains, thus allowing them to undergo gravitational planet–planet interactions and possibly maintain a nonzero obliquity. The TRAPPIST-1 system is in such a near-resonant configuration, making it plausible that TRAPPIST-1e has a nonzero obliquity. In this work, we use the ExoCAM general circulation model to study the possible climates of TRAPPIST-1e at varying obliquities and atmospheric compositions. We vary obliquity from 0° to 90° and the partial pressure of carbon dioxide from 0.0004 bar (modern Earth-like) to 1 bar. We find that models with a higher obliquity are hotter overall and have a smaller day–night temperature contrast than the lower-obliquity models, which is consistent with previous studies. Most significantly, the superrotating high-altitude jet becomes subrotating at high obliquity, thus impacting cloud and surface temperature patterns. As the amount of carbon dioxide increases, the climate of TRAPPIST-1e becomes hotter, cloudier, and less variable. From modeled thermal phase curves, we find that the impact of obliquity could potentially have observable consequences due to the effect of cloud coverage on the outgoing longwave radiation.

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Gialluca, Megan T., Rory Barnes, Victoria S. Meadows, Rodolfo Garcia, Jessica Birky, and Eric Agol. "The Implications of Thermal Hydrodynamic Atmospheric Escape on the TRAPPIST-1 Planets." Planetary Science Journal 5, no. 6 (June 1, 2024): 137. http://dx.doi.org/10.3847/psj/ad4454.

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Abstract JWST observations of the seven-planet TRAPPIST-1 system will provide an excellent opportunity to test outcomes of stellar-driven evolution of terrestrial planetary atmospheres, including atmospheric escape, ocean loss, and abiotic oxygen production. While most previous studies use a single luminosity evolution for the host star, we incorporate observational uncertainties in stellar mass, luminosity evolution, system age, and planetary parameters to statistically explore the plausible range of planetary atmospheric escape outcomes. We present probabilistic distributions of total water loss and oxygen production as a function of initial water content, for planets with initially pure water atmospheres and no interior–atmosphere exchange. We find that the interior planets are desiccated for initial water contents below 50 Earth oceans. For TRAPPIST-1e, f, g, and h, we report maximum water-loss ranges of 8.0 − 0.9 + 1.3 , 4.8 − 0.4 + 0.6 , 3.4 − 0.3 + 0.3 , and 0.8 − 0.1 + 0.2 Earth oceans, respectively, with corresponding maximum oxygen retention of 1290 − 75 + 75 , 800 − 40 + 40 , 560 − 25 + 30 , and 90 − 10 + 10 bars. We explore statistical constraints on initial water content imposed by current water content, which could inform evolutionary history and planet formation. If TRAPPIST-1b is airless while TRAPPIST-1c possesses a tenuous oxygen atmosphere, as initial JWST observations suggest, then our models predict an initial surface water content of 8.2 − 1.0 + 1.5 Earth oceans for these worlds, leading to the outer planets retaining >1.5 Earth oceans after entering the habitable zone. Even if TRAPPIST-1c is airless, surface water on the outer planets would not be precluded.

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Gressier, A., M. Mori, Q. Changeat, B. Edwards, J. P. Beaulieu, E. Marcq, and B. Charnay. "Near-infrared transmission spectrum of TRAPPIST-1 h using Hubble WFC3 G141 observations." Astronomy & Astrophysics 658 (February 2022): A133. http://dx.doi.org/10.1051/0004-6361/202142140.

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Context. The TRAPPIST-1 planetary system is favourable for transmission spectroscopy and offers the unique opportunity to study rocky planets with possibly non-primary envelopes. We present here the transmission spectrum of the seventh planet of the TRAPPIST-1 system, TRAPPIST-1 h (RP = 0.752 R⊕, Teq = 173 K) using Hubble Space Telescope (HST), Wide Field Camera 3 Grism 141 (WFC3/G141) data. Aims. Our purpose is to reduce the HST observations of the seventh planet of the TRAPPIST-1 system and, by testing a simple atmospheric hypothesis, to put a new constraint on the composition and the nature of the planet. Methods. First we extracted and corrected the raw data to obtain a transmission spectrum in the near-infrared (NIR) band (1.1–1.7 μm). TRAPPIST-1 is a cold M-dwarf and its activity could affect the transmission spectrum. We corrected for stellar modulations using three different stellar contamination models; while some fit the data better, they are statistically not significant and the conclusion remains unchanged concerning the presence or lack thereof of an atmosphere. Finally, using a Bayesian atmospheric retrieval code, we put new constraints on the atmosphere composition of TRAPPIST-1h. Results. According to the retrieval analysis, there is no evidence of molecular absorption in the NIR spectrum. This suggests the presence of a high cloud deck or a layer of photochemical hazes in either a primary atmosphere or a secondary atmosphere dominated by heavy species such as nitrogen. This result could even be the consequence of the lack of an atmosphere as the spectrum is better fitted using a flat line. Variations in the transit depth around 1.3 μm are likely due to remaining scattering noise and the results do not improve while changing the spectral resolution. TRAPPIST-1 h has probably lost its atmosphere or possesses a layer of clouds and hazes blocking the NIR signal. We cannot yet distinguish between a primary cloudy or a secondary clear envelope using HST/WFC3 data; however, in most cases with more than 3σ confidence, we can reject the hypothesis of a clear atmosphere dominated by hydrogen and helium. By testing the forced secondary atmospheric scenario, we find that a CO-rich atmosphere (i.e. with a volume mixing ratio of 0.2) is one of the best fits to the spectrum with a Bayes factor of 1.01, corresponding to a 2.1σ detection.

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KOVINCIC, IVANA, IVICA F. VUJICIC, MELINA SVABIC-VLAHOVIC, MIRJANA VULIC, MAJA GAGIC, and IRENE V. WESLEY. "Survival of Listeria monocytogenes During the Manufacture and Ripening of Trappist Cheese." Journal of Food Protection 54, no. 6 (June 1, 1991): 418–20. http://dx.doi.org/10.4315/0362-028x-54.6.418.

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Trappist cheese constitutes more than one-third of the semisoft cheese production in Yugoslavia. The ability of Listeria monocytogenes to survive the Trappist cheese-making process and persist during 90 d of ripening and storage was examined. Trappist cheese was manufactured from pasteurized milk (trials A, B, C) and from whey (trials D and E) inoculated with L. monocytogenes (2.46–5.38 log10 CFU/ml). An increase in L. monocytogenes counts was detected after 30 d of ripening in all of the five trials. After ripening and storage for 90 d, the L. monocytogenes counts ranged from 2.72–5.64 log10 CFU/g cheese. A decline in the population of L. monocytogenes was correlated with a decrease in cheese moisture and pH and with an increase in NaCl and titratable acidity.

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Lin, Zifan, Ryan J. MacDonald, Lisa Kaltenegger, and David J. Wilson. "Differentiating modern and prebiotic Earth scenarios for TRAPPIST-1e: high-resolution transmission spectra and predictions for JWST." Monthly Notices of the Royal Astronomical Society 505, no. 3 (June 3, 2021): 3562–78. http://dx.doi.org/10.1093/mnras/stab1486.

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ABSTRACT The TRAPPIST-1 system is a priority target for terrestrial exoplanet characterization. TRAPPIST-1e, residing in the habitable zone, will be observed during the James Webb Space Telescope (JWST) GTO Program. Here, we assess the prospects of differentiating between prebiotic and modern Earth scenarios for TRAPPIST-1e via transmission spectroscopy. Using updated TRAPPIST-1 stellar models from the Mega-MUSCLES survey, we compute self-consistent model atmospheres for a 1 bar prebiotic Earth scenario and two modern Earth scenarios (1 and 0.5 bar eroded atmosphere). Our modern and prebiotic high-resolution transmission spectra ($0.4\!-\! 20\, \rm{\mu m}$ at R ∼100 000) are made available online. We conduct a Bayesian atmospheric retrieval analysis to ascertain the molecular detectability, abundance measurements, and temperature constraints achievable for both scenarios with JWST. We demonstrate that JWST can differentiate between our prebiotic and modern Earth scenarios within 20 NIRSpec Prism transits via CH4 abundance measurements. However, JWST will struggle to detect O3 for our modern Earth scenario to $\gt 2\, \sigma$ confidence within the nominal mission lifetime (∼ 80 transits over 5 yr). The agnostic combination of N2O and/or O3 offers better prospects, with a predicted detection significance of $2.7\, \sigma$ with 100 Prism transits. We show that combining MIRI LRS transits with Prism data provides little improvement to atmospheric constraints compared to observing additional Prism transits. Though biosignatures will be challenging to detect for TRAPPIST-1e with JWST, the abundances for several important molecules – CO2, CH4, and H2O – can be measured to a precision of ≲ 0.7 dex (a factor of 5) within a 20 Prism transit JWST program.

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Ogihara, Masahiro, Eiichiro Kokubo, Ryuunosuke Nakano, and Takeru K. Suzuki. "Rapid-then-slow migration reproduces mass distribution of TRAPPIST-1 system." Astronomy & Astrophysics 658 (February 2022): A184. http://dx.doi.org/10.1051/0004-6361/202142354.

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Context. The TRAPPIST-1 system is an iconic planetary system in various aspects (e.g., habitability, resonant relation, and multiplicity) and hence has attracted considerable attention. The mass distribution of the TRAPPIST-1 planets is characterized by two features: the two inner planets are large, and the masses of the four planets in the outer orbit increase with orbital distance. The origin of these features cannot be explained by previous formation models. Aims. We investigate whether the mass distribution of the TRAPPIST-1 system can be reproduced by a planet formation model using N-body simulations. Methods. We used a gas disk evolution model around a low-mass star constructed by considering disk winds and followed the growth and orbital migration from planetary embryos with the isolation mass, which increases with orbital distance. Results. As a result, we find that from the initial phase, planets in inner orbits undergo rapid orbital migration, and the coalescence growth near the inner disk edge is enhanced. This allows the inner planets to grow larger. Meanwhile, compared with the inner planets, planets in outer orbits migrate more slowly and do not frequently collide with neighboring planets. Therefore, the trend of increasing mass toward the outer orbit, called reversed mass ranking, is maintained. The final mass distribution approximately agrees with the two features of the mass distribution in the TRAPPIST-1 system. Conclusions. We discover that the mass distribution in the TRAPPIST-1 system can be reproduced when embryos experience rapid migration and become trapped near the disk inner edge, and then more massive embryos undergo slower migration. This migration transition can be achieved naturally in a disk evolution model with disk winds.

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Đošović, Vladimir, Bojan Novakovć, Branislav Vukotć, and Milan M. Ćirković. "Water transport throughout the TRAPPIST-1 system: the role of planetesimals." Monthly Notices of the Royal Astronomical Society 499, no. 4 (June 27, 2020): 4626–37. http://dx.doi.org/10.1093/mnras/staa1833.

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ABSTRACT Observational data suggest that a belt of planetesimals is expected close to the snow line in protoplanetary discs. Assuming there is such a belt in the TRAPPIST-1 system, we examine possibilities of water delivery to the planets via planetesimals from the belt. The study is accomplished by numerical simulations of dynamical evolution of a hypothetical planetesimal belt. Our results show that the inner part of the belt is dynamically unstable and planetesimals located in this region are quickly scattered away, with many of them entering the region around the planets. The main dynamical mechanism responsible for the instability are close encounters with the outermost planet Trappist-1h. A low-order mean-motion resonance 2:3 with Trappist-1h, located in the same region, also contributes to the objects transport. In our nominal model, the planets have received a non-negligible amount of water, with the smallest amount of 15 per cent of the current Earth’s water amount (EWA) being delivered to the planet 1b, while the planets Trappist-1e and Trappist-1g have received more than 60 per cent of the EWA. We have found that while the estimated efficiency of water transport to the planets is robust, the amount of water delivered to each planet may vary significantly, depending on the initial masses and orbits of the planets. The estimated dynamical ‘half-lives’ have shown that the impactors’ source region should be emptied in less then 1 Myr. Therefore, the obtained results suggest that the transport of planetesimals through the system preferably occurs during an early phase of the planetary system evolution.

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Basant, Ritvik, Jeremy Dietrich, and Dániel Apai. "Prediction of an Earth-sized Planet Formed in the Habitable Zone of the SPECULOOS-2 System." Research Notes of the AAS 6, no. 10 (October 19, 2022): 213. http://dx.doi.org/10.3847/2515-5172/ac9ab8.

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Abstract Transiting planets in the nearby TRAPPIST-1 system provide rare examples of habitable zone (HZ), Earth-sized planets that can be characterized via transmission spectroscopy. However, these present-day HZ planets likely formed interior to HZ and probably underwent an evolution very different from that of Earth. We present the integrative analysis of the planetary architecture of the recently discovered planetary system SPECULOOS-2. Our analysis answers the question: If there are additional exoplanets in the SPECULOOS-2 system, what are their orbital and physical properties? We predict an Earth-sized planet in the habitable zone (P ∼ 14.5–18.2 days). In contrast to TRAPPIST-1e, this predicted planet most likely completed its formation inside the habitable zone. If confirmed, this planet will offer an Earth-sized, habitable zone planet that is likely to have an evolutionary path more similar to Earth than those in the TRAPPIST-1 system.

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Christodoulou, Dimitris M., and Demosthenes Kazanas. "Predicting Additional Planets in TRAPPIST-1." Research Notes of the AAS 3, no. 3 (March 15, 2019): 50. http://dx.doi.org/10.3847/2515-5172/ab0e13.

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Morris, Brett M., Eric Agol, James R. A. Davenport, and Suzanne L. Hawley. "Possible Bright Starspots on TRAPPIST-1." Astrophysical Journal 857, no. 1 (April 11, 2018): 39. http://dx.doi.org/10.3847/1538-4357/aab6a5.

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Maltagliati, Luca. "Investigating TRAPPIST-1 e atmospheric scenarios." Nature Astronomy 5, no. 6 (June 2021): 530. http://dx.doi.org/10.1038/s41550-021-01410-3.

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Hay, Hamish C. F. C., and Isamu Matsuyama. "Tides Between the TRAPPIST-1 Planets." Astrophysical Journal 875, no. 1 (April 9, 2019): 22. http://dx.doi.org/10.3847/1538-4357/ab0c21.

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Kipping, David. "Predicting The Orbit of TRAPPIST-1i." Research Notes of the AAS 2, no. 3 (August 3, 2018): 136. http://dx.doi.org/10.3847/2515-5172/aad6e8.

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Tarr, Kathleen. "The Trappist Monk and Pasternak's Tree." Sewanee Review 121, no. 3 (2013): 449–59. http://dx.doi.org/10.1353/sew.2013.0062.

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Dong, Chuanfei, Meng Jin, Manasvi Lingam, Vladimir S. Airapetian, Yingjuan Ma, and Bart van der Holst. "Atmospheric escape from the TRAPPIST-1 planets and implications for habitability." Proceedings of the National Academy of Sciences 115, no. 2 (December 28, 2017): 260–65. http://dx.doi.org/10.1073/pnas.1708010115.

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The presence of an atmosphere over sufficiently long timescales is widely perceived as one of the most prominent criteria associated with planetary surface habitability. We address the crucial question of whether the seven Earth-sized planets transiting the recently discovered ultracool dwarf star TRAPPIST-1 are capable of retaining their atmospheres. To this effect, we carry out numerical simulations to characterize the stellar wind of TRAPPIST-1 and the atmospheric ion escape rates for all of the seven planets. We also estimate the escape rates analytically and demonstrate that they are in good agreement with the numerical results. We conclude that the outer planets of the TRAPPIST-1 system are capable of retaining their atmospheres over billion-year timescales. The consequences arising from our results are also explored in the context of abiogenesis, biodiversity, and searches for future exoplanets. In light of the many unknowns and assumptions involved, we recommend that these conclusions must be interpreted with due caution.

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Mandt, Kathleen, Adrienn Luspay-Kuti, Jacob Lustig-Yaeger, Ryan Felton, and Shawn Domagal-Goldman. "TRAPPIST-1h as an Exo-Titan. I. The Role of Assumptions about Atmospheric Parameters in Understanding an Exoplanet Atmosphere." Astrophysical Journal 930, no. 1 (May 1, 2022): 73. http://dx.doi.org/10.3847/1538-4357/ac59bb.

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Abstract The TRAPPIST-1 system is home to at least seven terrestrial planets and is a target of interest for future James Webb Space Telescope (JWST) observations. Additionally, these planets will be of interest to future missions making observations in the ultraviolet (UV). Although several of these planets are located in the traditional habitable zone, where liquid water could exist on the surface, TRAPPIST-1h is interesting to explore as a potentially habitable ocean world analog. In this study, we evaluate the observability of a Titan-like atmosphere on TRAPPIST-1h. The ability of the JWST or a future UV mission to detect specific species in the atmosphere at TRAPPIST-1h will depend on how far each species extends from the surface. In order to understand the conditions required for detection, we evaluate the input parameters used in one-dimensional models to simulate the structure of Titan-like atmospheres. These parameters include surface temperature and pressure, temperature profile as a function of distance from the surface, composition of the minor species relative to N2, and the eddy diffusion coefficient. We find that JWST simulated spectra for cloud- and haze-free atmospheres are most sensitive to surface temperature, temperature gradients with altitude, and surface pressure. The importance of temperature gradients in JWST observations shows that a simple isothermal scale height is not ideal for determining temperature or atmospheric mean molecular mass in transit spectra from exoplanet atmospheres. We demonstrate that UV transmission spectra are sensitive to the upper atmosphere, where the exobase can be used to approximate the vertical extent of the atmosphere.

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Myttenaere, Bernard De. "Valorisation touristique des bières trappistes en Wallonie." Mondes du tourisme, no. 7 (June 1, 2013): 68–83. http://dx.doi.org/10.4000/tourisme.186.

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Soung Yee, L., P. Álvarez, E. Martin, E. Cortina, and C. Ferrer. "Test of the TRAPPISTe monolithic detector system." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 731 (December 2013): 141–45. http://dx.doi.org/10.1016/j.nima.2013.03.052.

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Cortina, E., L. Soung Yee, C. Renaux, D. Flandre, and E. Martin. "TRAPPISTe pixel sensor with 2μm SOI technology." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 633 (May 2011): S19—S21. http://dx.doi.org/10.1016/j.nima.2010.06.109.

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Quinn, Justin, Tim Kendall, Richard Kirkland, and Luke Gibbons. "The Trappings of Politics." Irish Review (1986-), no. 21 (1997): 159. http://dx.doi.org/10.2307/29735877.

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Oenbring, Raymond, and Matthias Klumm. "The trappings of order." English World-Wide 43, no. 1 (November 17, 2021): 66–95. http://dx.doi.org/10.1075/eww.21020.oen.

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Abstract This study builds off of previous research into Caribbean Standard Englishes (which has largely used newspaper genres) by comparing the rates of features found in corpora of Bahamian, Jamaican, British, and American administrative writing, paying particular attention to whether and how the noted formality of Caribbean Standard Englishes manifests itself in administrative writing. The study employs expanded versions of ICE administrative subcorpora for the analysis. Features analyzed include lexis, orthography, as well as different morphosyntactic constructions such as be-passives and modals of obligation and necessity. The study finds that the contemporary British administrative writing corpus contains the most informal lexical choice of the national corpora studied, problematizing a Caribbean folk narrative that associates formality in administrative language and practice with Britishness.

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Martin, John Frederick. "The Trappings of Democracy." Historically Speaking 14, no. 4 (2013): 2–7. http://dx.doi.org/10.1353/hsp.2013.0039.

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Brewer, Paul R. "The Trappings of Science." Science Communication 35, no. 3 (September 7, 2012): 311–33. http://dx.doi.org/10.1177/1075547012454599.

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Grier, David Alan. "The Trappings of Power." Computer 46, no. 11 (November 2013): 120. http://dx.doi.org/10.1109/mc.2013.399.

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47

Brain, J. B. "Mariannhill monastery, 1882-1982." New Contree 13 (July 11, 2024): 5. http://dx.doi.org/10.4102/nc.v13i0.785.

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The Mariannhill monastery was established in 1882 on the farm Zeekoegat in Natal by the Trappist monks who, before any direct evangelization, cultivated the large and productive monastery farm and erected the necessary buildings. Formal mission work did not begin until 1884 and by 1898, with 185 monks, Mariannhill had become the largest abbey in the world. It was separated in 1909 from the Trappist order and became a separate missionary congregation known as the Congregation of Missionaries of Mariannhill. Today Mariannhill missionaries are at work not only in Natal, but also in the Transkei, Zimbabwe, New Guinea, and Brazil.

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Turbet, Martin, Thomas J. Fauchez, Denis E. Sergeev, Ian A. Boutle, Kostas Tsigaridis, Michael J. Way, Eric T. Wolf, et al. "The TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI). I. Dry Cases—The Fellowship of the GCMs." Planetary Science Journal 3, no. 9 (September 1, 2022): 211. http://dx.doi.org/10.3847/psj/ac6cf0.

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Abstract With the commissioning of powerful, new-generation telescopes such as the James Webb Space Telescope (JWST) and the ground-based Extremely Large Telescopes, the first characterization of a high molecular weight atmosphere around a temperate rocky exoplanet is imminent. Atmospheric simulations and synthetic observables of target exoplanets are essential to prepare and interpret these observations. Here we report the results of the first part of the TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI) project, which compares 3D numerical simulations performed with four state-of-the-art global climate models (ExoCAM, LMD-Generic, ROCKE-3D, Unified Model) for the potentially habitable target TRAPPIST-1e. In this first part, we present the results of dry atmospheric simulations. These simulations serve as a benchmark to test how radiative transfer, subgrid-scale mixing (dry turbulence and convection), and large-scale dynamics impact the climate of TRAPPIST-1e and consequently the transit spectroscopy signature as seen by JWST. To first order, the four models give results in good agreement. The intermodel spread in the global mean surface temperature amounts to 7 K (6 K) for the N2-dominated (CO2-dominated) atmosphere. The radiative fluxes are also remarkably similar (intermodel variations less than 5%), from the surface (1 bar) up to atmospheric pressures ∼5 mbar. Moderate differences between the models appear in the atmospheric circulation pattern (winds) and the (stratospheric) thermal structure. These differences arise between the models from (1) large-scale dynamics, because TRAPPIST-1e lies at the tipping point between two different circulation regimes (fast and Rhines rotators) in which the models can be alternatively trapped, and (2) parameterizations used in the upper atmosphere such as numerical damping.

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Howard, Ward S., Adam F. Kowalski, Laura Flagg, Meredith A. MacGregor, Olivia Lim, Michael Radica, Caroline Piaulet, et al. "Characterizing the Near-infrared Spectra of Flares from TRAPPIST-1 during JWST Transit Spectroscopy Observations." Astrophysical Journal 959, no. 1 (December 1, 2023): 64. http://dx.doi.org/10.3847/1538-4357/acfe75.

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Abstract We present the first analysis of JWST near-infrared spectroscopy of stellar flares from TRAPPIST-1 during transits of rocky exoplanets. Four flares were observed from 0.6–2.8 μm with the Near Infrared Imager and Slitless Spectrograph and 0.6–3.5 μm with the Near Infrared Spectrograph during transits of TRAPPIST-1b, f, and g. We discover Pα and Brβ line emission and characterize flare continuum at wavelengths from 1–3.5 μm for the first time. Observed lines include Hα, Pα–Pϵ, Brβ, He i λ0.7062 μm, two Ca ii infrared triplet (IRT) lines, and the He i IRT. We observe a reversed Paschen decrement from Pα–Pγ alongside changes in the light-curve shapes of these lines. The continuum of all four flares is well described by blackbody emission with an effective temperature below 5300 K, lower than the temperatures typically observed at optical wavelengths. The 0.6–1 μm spectra were convolved with the Transiting Exoplanet Survey Satellite (TESS) response, enabling us to measure the flare rate of TRAPPIST-1 in the TESS bandpass. We find flares of 1030 erg, large enough to impact transit spectra occur at a rate of 3.6 − 1.3 + 2.1 flare day−1, ∼10× higher than previous predictions from K2. We measure the amount of flare contamination at 2 μm for the TRAPPIST-1b and f transits to be 500 ± 450 and 2100 ± 400 ppm, respectively. We find up to 80% of flare contamination can be removed, with mitigation most effective from 1.0–2.4 μm. These results suggest transits affected by flares may still be useful for atmospheric characterization efforts.

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Davoudi, Fatemeh, Benjamin V. Rackham, Michaël Gillon, Julien de Wit, Adam J. Burgasser, Laetitia Delrez, Aishwarya Iyer, and Elsa Ducrot. "Updated Spectral Characteristics for the Ultracool Dwarf TRAPPIST-1." Astrophysical Journal Letters 970, no. 1 (July 1, 2024): L4. http://dx.doi.org/10.3847/2041-8213/ad5c6c.

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Abstract A comprehensive infrared spectroscopic study of star TRAPPIST-1 is a crucial step toward the detailed examination of its planets. While the presence of Earth’s atmosphere has limited the spectral extent of such a study up to now, the Near Infrared Imager and Slitless Spectrograph (NIRISS) and the Near Infrared Spectrograph instruments aboard the James Webb Space Telescope (JWST) can now yield the 0.6–5 μm spectral energy distribution (SED) of the star. Here we translate TRAPPIST-1's SED into tight constraints on its luminosity (L bol = 0.000566 ± 0.000022 L ⊙), effective temperature (T eff = 2569 ± 28 K), and metallicity ([Fe/H] = 0.052 ± 0.073) and investigate the behavior of its gravity-sensitive indices. Through band-by-band comparisons of the NIRISS and ground-based spectra, TRAPPIST-1 exhibits a blend of both field source and intermediate-gravity spectral characteristics, suggesting that the star is likely a field-age source with spectral features reminiscent of young objects. We also employ photospheric modeling incorporating theoretical and JWST spectra to constrain stellar surface heterogeneities, finding that the limited fidelity of current stellar spectral models precludes definitive constraints on the physical parameters of the distinct spectral components giving rise to TRAPPIST-1's photospheric heterogeneity and variability. In addition, we find intermodel differences in the inferences of properties (e.g., the effective temperature) over one order of magnitude larger than the instrument-driven uncertainties (∼100 K vs. ∼4 K), pointing toward a model-driven accuracy wall. Our findings call for a new generation of stellar models to support the optimal mining of JWST data and further constraining stellar—and ultimately planetary—properties.

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Journal articles on the topic 'Trappists'

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