arXiv subjects

Kevin Wagner

Publications and source records attributed to Kevin Wagner.

At least 19 recordsLinked to original sources

arXiv2026

Upgrading LBTI/NOMIC with a quadruple annular groove phase mask and GeoSnap detector for imaging nearby, habitable-zone exoplanets

The Large Binocular Telescope Interferometer (LBTI)'s Nulling-Optimized Mid-Infrared Camera (NOMIC) is among the most capable thermal-infrared imaging systems available for high-contrast, high-angular-resolution astronomical observations. Here we describe two in-progress upgrades to LBTI/NOMIC: (1) the design, fabrication, and installation of a quadruple annular groove phase mask (Q-AGPM) coronagraph, and (2) the installation of a 13 micron-cutoff Teledyne GeoSnap array. The Q-AGPM is the first coronagraph to be installed within NOMIC and one of the first optimized for N-band (~11 micron) observations. It places four annular groove phase masks on a single diamond substrate so that, in the LBTI dual-aperture imaging mode, each of the two telescope beams can be chopped between a pair of masks without loss of observing efficiency. The GeoSnap array will replace NOMIC's original AQUARIUS array, delivering higher quantum efficiency, larger well depth, faster and more linear readout, and freedom from the excess low-frequency noise that requires aggressive chopping. Together these upgrades substantially improve the achievable contrast and sensitivity at small angular separations. We also present a high-contrast Fizeau imaging sequence obtained with LBTI's new FFTCam fringe tracker, which confirms the interferometric gain over a single aperture through injection/recovery tests: relative to an equal-time single aperture exposure, the S/N = 3 contrast is a factor of ~2-4 deeper across 0.2-1 arcsec, spanning the contrast- and background-limited regimes. Finally, we describe the role of the upgraded LBTI/NOMIC instrument within the Breakthrough Watch program at the University of Arizona, which aims to perform the deepest observations yet of the habitable zones of the nearest single Sun-like stars.

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arXiv2026

The Interstellar Laser Beacons Hypothesis and the Cosmic Lighthouses Project

In this paper, we argue that in a realistic, resource-limited scenario senders whose intent is to maximize successful communication at the lowest cost will utilize very long-lived, pulsed beacons. Further, we argue that mass-producible laser beacons with simpler technology ($\mu$s or ms pulses instead of ultrashort fs pulses) are more optimal if placed on interstellar orbits. Our extensive, existing surveys are mostly blind to the $\mu$s/ms-second universe and to such beacons. We show, however, that the convergence of three technologies (massively parallel processing, ultra high-speed CMOS detectors, and broadband, mass-producible diffractive-refractive lenses) now offer an exciting opportunity for a low-cost survey of the $\mu$second sky. Such survey would be astrophysically compelling and, with even low-cost telescopes, could place volume-complete constraints on interstellar beacons within twenty parsecss.

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arXiv2026

A Scalable Path to Astrometric Exomoon Discoveries with the Nautilus Space Observatory

Moons orbiting exoplanets (exomoons) can be detected through the reflex motion they impart to their host planet, which is recoverable in relative star-planet astrometric time series. The signal grows with moon mass and orbital separation and decreases with distance, so the nearest and least massive imaged planets are the most favorable targets. Recovering small (<Earth-mass) moons requires continuous, long-baseline, high-precision monitoring that is only practical with a dedicated or nearly dedicated facility. Building on recent simulations of astrometric exomoon detection and of the resulting population yields, we argue that the scalable, replicable architecture of the Nautilus Space Observatory is uniquely suited to this problem, and we outline a staged campaign. In an initial phase, one or a few small apertures target the nearest imaged giant planets--a high-reward but low-probability search focused on the closest stars. As the array is built out, the astrometric noise floor decreases and the same technique extends the search to the nearest such systems among nearby stars of spectral type K and earlier. This would be performed in parallel with high-contrast imaging and spectral characterization of the host planets and in synergy with a companion starshade concept for imaging Earth-like planets around the same nearby stars. Nautilus thus provides a scalable path from the first detection of a nearby exomoon toward a systematic search for exomoons around the closest stars.

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arXiv2026

Nautilus Space Observatory: The Evolution of Planets and their Atmospheres

We are just beginning to explore the billion-year evolution from nascent planets in disks to mature planetary systems. Recent discoveries hint at demographic and atmospheric differences between young planets and their Gyr-old counterparts, but current facilities are limited - particularly in their ability to conduct statistical atmospheric studies over a broad period range. This white paper outlines compelling science achievable with the Nautilus Space Observatory, a proposed constellation of large-diameter space telescopes. We identify four primary scientific objectives: (1) determining the timescales over which planets evolve into sub-Neptunes and super-Earths; (2) tracking the temporal evolution of atmospheric mass-loss rates; (3) characterizing the evolution of the atmospheric mean molecular weight and C/O ratio; and (4) identifying the emergence of Helium-dominated worlds. Answering these questions requires the high spatial resolution, broad-wavelength coverage, large effective area, and parallelized multiple units that Nautilus provides. By isolating the physical processes that govern the evolution of planets and their atmospheres, these science objectives directly support NASA's Cosmic Origins and Exoplanet Exploration Programs.

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arXiv2026

Direct Imaging Discovery of Giant Exoplanet $\beta$ Pictoris d: A Decade-Long Game of Hide-and-Seek

We report the direct imaging discovery of a third exoplanet in the $\beta$ Pictoris system. We detect $\beta$ Pictoris d ($\beta$ Pic d) in non-coronagraphic observations obtained with VLT/ERIS as well as multi-epoch archival datasets from JWST/NIRCam and VLT/SPHERE. Astrometric measurements over an 11-year baseline demonstrate that it is consistent with a gravitationally-bound source with orbital motion. Joint multi-planet orbit fits of all three planets in the system yield a semi-major axis of $26.0^{+2.2}_{-6.1}$ au and inclination $89.0^{+0.7}_{-0.6}$ deg for planet d. $\beta$ Pic d has a larger orbital semi-major axis than the other known planets in the system, but is coplanar with the inner two planets, and its orbit is consistent with sculpting the inner edge of the debris disk. $\beta$ Pic d has a contrast of $\Delta L^{\prime}=12.11\pm0.15$ mag, with colors and luminosity that closely match those of 51 Eri b, another exoplanet in the $\beta$ Pictoris moving group. Its VLT/ERIS and JWST/NIRCam colors are distinct from those of free-floating planetary-mass objects of a similar age and temperature. Its red $F410M-F444W$ color indicates strong CO$_2$ absorption in its atmosphere and suggests significant enhancement in metals compared to free-floating objects. From the ATMO hot-start evolutionary models, we estimate an effective temperature of $600^{+45}_{-60}$ K and mass of $2.4\pm0.6$ $M_{\rm Jup}$, which also closely matches similar estimates for 51 Eri b. $\beta$ Pic d is among the lowest-mass exoplanets imaged from the ground. This discovery highlights the deep sensitivity achievable with ground-based imaging in the mid-infrared and the discovery potential of future high-contrast observations with the Extremely Large Telescope.

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arXiv2026

Exploring Exoplanets with Interferometry

(Extract from the Executive Summary) Humanity stands at the threshold of answering one of its most profound questions: Does life exist beyond Earth? Ongoing and upcoming space missions, together with powerful ground-based instruments, have prepared the way for a transformational next step - the detailed characterization of Earth analogs orbiting Sun-like and other stars and the search for atmospheric biosignatures that may indicate life. Within this context, the European Space Agency's Voyage 2050 process has identified the direct detection of thermal emission from temperate terrestrial exoplanets in the mid-infrared (mid-IR) as a top scientific priority. The Large Interferometer For Exoplanets (LIFE) - a space-based, mid-IR nulling interferometer - is designed to meet this goal. LIFE will be capable of detecting climate-relevant gases such as CO$_2$ and H$_2$O, identifying classical biosignatures like O$_3$ and CH$_4$, and probing additional, non-classical biosignatures. It will also provide key data for determining planetary radius, albedo, and temperature, which are essential for assessing habitability. In parallel, the U.S. National Academy has recommended a complementary mission now called the Habitable Worlds Observatory (HWO) - a ~6-meter space telescope equipped with advanced coronagraphs to suppress starlight by a factor of ~10$^{10}$ across the visible and possibly into the near-infrared and near-ultraviolet. Together, LIFE and HWO offer synergistic capabilities, enabling a comprehensive and robust assessment of the prevalence of life-bearing exoplanets in our galactic neighbourhood - a first in human history. By uniting an international and interdisciplinary community of scientists and engineers, LIFE offers a credible pathway toward the direct detection and characterization of potentially habitable - and even inhabited - worlds.

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arXiv2026

Forecasting Catastrophe: Constraints on the Fomalhaut Main Belt Planetesimal Population from Observed Collisional Remnants

Catastrophic planetesimal disruptions offer a unique opportunity to study and characterize large planetesimal populations in exoplanetary systems that are not currently detectable by modern observatories. The unexpected discovery of a second collision event in the Fomalhaut system raises important questions about the planetesimal population and dynamical state inside the Fomalhaut main belt that led to two collisions in 20 years. We present a statistical model developed and applied to the archetypal Fomalhaut system to provide new constraints on the bulk properties of the planetesimals in Fomalhaut's main belt. Utilizing the constraints provided by the spatially resolved Fomalhaut cs1 and cs2 collision events, we retrieve the belt parameters that best reproduce the observed collision rate while remaining consistent with the system's age and dust mass. Our best-fit model suggests a total main belt mass of 200-360 $M_{\oplus}$, with the transition from a collisionally evolved to a primordial planetesimal population occurring at a radius of $115_{-10}^{+30}$ km and a maximum planetesimal radius of $380_{-202}^{+643}$ km. We estimate a catastrophic collision rate of $0.086_{-0.048}^{+0.067}$ collision events per year for planetesimals with radii $\ge$ 100 km in the region interior to the main belt. Our findings show that further observable collisions are likely, motivating continued monitoring of Fomalhaut and other nearby debris disks.

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arXiv2026

Time-variable Scattered Light in Herbig Disks Observed with Subaru/SCExAO

Using the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument, we present near-infrared K-band polarimetric imaging of nine Herbig stars selected from a volume-limited sample within 200 pc. We detect the disks around MWC 480, HD 163296, and HD 143006 for the first time with SCExAO, and compare these observations with previous VLT/SPHERE datasets to identify surface-brightness variability. In MWC 480, we resolve two azimuthal brightness dips near the disk minor axis and find evidence that one of them shifted between 2021 and 2022. In HD 163296, we identify an apparent linear azimuthal motion of a localized peak in polarized intensity along the outer ring over a 15-month baseline. The rapid motion of these features relative to the local Keplerian velocity suggests that the observed variability is driven by changing illumination rather than physical material motion. Due to uncertainties in the underlying scattering background, however, we cannot determine the precise physical origin of the variability. No significant disk variability is detected in HD 143006 over a 10-month baseline. We also report the first detection of a protoplanetary disk using the fast-PDI mode on SCExAO, illustrating both the promise and current limitations of this observing mode. Finally, we report non-detections toward HD 144432, HD 56895, PDS 76, HIP 80425, HD 148352, and HIP 81474. All non-detections with Meeus classifications belong to Group II systems and are likely self-shadowed. For these six systems, we measure the system-integrated polarization fraction and angle of linear polarization, providing quantitative constraints on their unresolved circumstellar environments.

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arXiv2025

Are We There Yet? Challenges in Quantifying the Frequency of Earth Analogs in the Habitable Zone

Searching for life elsewhere in the universe is one of the most highly prioritized pursuits in astronomy today. However, the ability to observe evidence of Earth-like life through biosignatures is limited by the number of planets in the solar neighborhood with conditions similar to Earth. The occurrence rate of Earth-like planets in the habitable zones of Sun-like stars, $\eta_{\oplus}$, is therefore crucial for addressing the apparent lack of consensus on its value in the literature. Here we present a review of the current understanding of $\eta_{\oplus}$. We first provide definitions for parameters that contribute to $\eta_{\oplus}$. Then, we discuss the previous and current estimated parameter values and the context of the limitations on the analyses that produced these estimates. We compile an extensive list of the factors that go into any calculation of $\eta_{\oplus}$, and how detection techniques and surveys differ in their sensitivity and ability to accurately constrain $\eta_{\oplus}$. Understanding and refining the value of $\eta_{\oplus}$ is crucial for upcoming missions and telescopes, such as the planned Habitable Worlds Observatory and the Large Interferometer for Exoplanets, which aim to search for biosignatures on exoplanets in the solar neighborhood.

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arXiv2025

A Scalable MVDR Beamforming Algorithm That is Linear in the Number of Antennas

The Minimum Variance Distortionless Response (MVDR) beamforming technique is widely applied in array systems to mitigate interference. However, applying MVDR to large arrays is computationally challenging; its computational complexity scales cubically with the number of antenna elements. In this paper, we introduce a scalable MVDR beamforming method tailored for massive arrays. Our approach, which is specific to scenarios where the signal of interest is below the noise floor (e.g.,~GPS), leverages the Sherman-Morrison formula, low-rank Singular Value Decomposition (SVD) approximations, and algebraic manipulation. Using our approach, we reduce the computational complexity from cubic to linear in the number of antennas. We evaluate the proposed method through simulations, comparing its computational efficiency and beamforming accuracy with the conventional MVDR approach. Our method significantly reduces the computational load while maintaining high beamforming accuracy for large-scale arrays. This solution holds promise for real-time applications of MVDR beamforming in fields like radar, sonar, and wireless communications, where massive antenna arrays are proliferating.

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arXiv2025

Astrometric Methods for Detecting Exomoons Orbiting Imaged Exoplanets: Prospects for Detecting Moons Orbiting a Giant Planet in $\alpha$ Centauri A's Habitable Zone

Nearby giant exoplanets offer an opportunity to search for moons (exomoons) orbiting them. Here, we present a simulation framework for investigating the possibilities of detecting exomoons via their astrometric signal in planet-to-star relative astrometry. We focus our simulations on $\alpha$ Centauri A, orbited by a hypothetical giant planet consistent with candidate detections in Very Large Telescope and James Webb Space Telescope observations. We consider a variety of observatory architectures capable of searching for exomoons, including upcoming facilities and also a hypothetical dedicated facility $-$ e.g., a purpose-built space telescope with diameter = 3m, central observing wavelength of 500 nm, and contrast-limited performance of $\sim$10$^{-9}$ in 1 hr observations. We find that such a facility would be capable of detecting $\sim$Earth-mass moons in a five year campaign, assuming a Saturn-mass planet. More generally, we simulate expected detection limits for a variety of levels of astrometric precision. We find that moons as small as $\sim$0.2 M$_\oplus$ on orbital periods of 4$-$30 days can be detected with astrometric precision of 0.1 mas and observing cadence of 1 hr over a five year campaign. Additionally, we find that a 39m ground-based telescope can detect Earth-sized exomoons orbiting the same hypothetical planet with a more modest observing cadence of one day. We discuss these results as motivation for a dedicated space observatory as well as a more detailed study of the physical parameters of a greater variety of star-planet-moon systems.

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arXiv2025

Wide Separation Planets In Time (WISPIT): Discovery of a Gap H$\alpha$ Protoplanet WISPIT 2b with MagAO-X

Excellent (<25 mas) H$_{\alpha}$ images of the star TYC 5709-354-1 led to the discovery of a rare H$_{\alpha}$ protoplanet. This star was discovered by the WISPIT survey to have a large multi-ring transitional disk, and is hereafter WISPIT 2. Our H$_{\alpha}$ images of 2025, April 13 and April 16 discovered an accreting (H$_{\alpha}$ in emission) protoplanet: WISPIT 2b (r=309.43$\pm$1.56 mas; (~54 au deprojected), PA=242.21$\pm$0.41 degrees) likely clearing a dust-free gap between the two brightest dust rings in the transitional disk. Our SNR=12.5 detection gave an H$_{\alpha}$ ASDI contrast of (6.5$\pm$0.5)x10$^{-4}$ and a H$_{\alpha}$ line flux of (1.29$\pm$0.28)x10$^{-15}$ erg/s/cm$^2$. We also present L' photometry from LBT/LMIRcam of the planet (L'=15.30$\pm$0.05 mag) which, when coupled with an age of 5.1$^{+2.4}_{-1.3}$ Myr, yields a planet mass estimate of 5.3$\pm$1.0 Mjup from the DUSTY evolutionary models. WISPIT 2b is accreting at 2.25$^{-0.17}_{+3.75}$x10$^{-12}$ Msun/yr. WISPIT 2b is very similar to the other H$_{\alpha}$ protoplanets in terms of mass, age, flux, and accretion rate. The inclination of the system (${\it i}$=44 degrees) is also, surprisingly, very similar to the other known H$\alpha$ protoplanet systems which all cluster from 37$\leq{\it i}\leq$52 degrees. We argue this clustering has only a ~1.0% (2.6 sigma) probability of occurring randomly, and so we speculate that magnetospherical accretion might have a preferred inclination range (~37-52 degrees) for the direct (cloud free, low extinction) line of sight to the H-alpha line formation/shock region. We also find at 110mas (~15au deprojected) a close companion candidate (CC1) which may be consistent with an inner dusty 9$\pm$4 Mjup planet.

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arXiv2025

Discovery of H$\alpha$ Emission from a Protoplanet Candidate Around the Young Star 2MASS J16120668-3010270 with MagAO-X

2MASS J16120668-3010270 (hereafter 2MJ1612) is a young M0 star that hosts a protoplanetary disk in the Upper Scorpious star-forming region. Recent ALMA observations of 2MJ1612 show a mildly inclined disk ($i$=37$^\circ$) with a large dust-depleted gap (R$_\text{cav}\approx$0.4" or 53 au). We present high-contrast H$\alpha$ observations from MagAO-X on the 6.5m Magellan Telescope and new high resolution sub-mm dust continuum observations with ALMA of 2MJ1612. On both 2025 April 13 and 16, we recovered a point source with H$\alpha$ excess with SNR $\gtrsim$5 within the disk gap in our MagAO-X Angular and Spectral Differential (ASDI) images at a separation of 141.96$\pm$2.10 mas (23.45$\pm$0.29 au deprojected) from the star and position angle (PA)= 159.00$\pm$0.55$^\circ$. Furthermore, this H$\alpha$ source is within close proximity to a K band point source in SPHERE/IRDIS observation taken on 2023 July 21 \citep{sphere2025sub}. The astrometric offset between the K band and H$\alpha$ source can be explained by orbital motion of a bound companion. Thus our observations can be best explained by the discovery of an accreting protoplanet, 2MJ1612 b, with an estimated mass of 4$M_\text{Jup}$ and H$\alpha$ line flux ranging from (29.7 $\pm$7.5)$\times$10$^{-16}$ ergs/s/cm$^2$ to (8.2$\pm$3.4)$\times$10$^{-16}$ ergs/s/cm$^2$. 2MJ1612 b is likely the third example of an accreting H$\alpha$ protoplanet responsible for carving the gap in its host disk, joining PDS 70b and c. Further study is necessary to confirm and characterize this protoplanet candidate and to identify any additional protoplanets that may also play a role in shaping the gap.

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arXiv2025

Worlds Next Door: A Candidate Giant Planet Imaged in the Habitable Zone of $\alpha$ Cen A. II. Binary Star Modeling, Planet and Exozodi Search, and Sensitivity Analysis

JWST observed our closest solar twin, $\alpha$ Cen A, with the MIRI coronagraph in F1550C (15.5 $\mu$m) at three distinct epochs between August 2024 and April 2025. For the first time with JWST, we demonstrate the application of reference star differential imaging to simultaneously subtract the coronagraphic image of a primary star and the point spread function (PSF) of its binary companion to conduct a deep search for exoplanets and dust emission. We achieve a typical 5$\sigma$ point source contrast sensitivity between $\sim$$10^{-5}$-$10^{-4}$ at separations $\gtrsim$ 1" and an exozodiacal disk (coplanar with $\alpha$ Cen AB) sensitivity of $\sim$5-8$\times$ the Solar System's zodiacal cloud around $\alpha$ Cen A. The latter is an extraordinary limit, representing the deepest sensitivity to exozodiacal disks achieved for any stellar system to date. Post-processing with the PCA-KLIP algorithm reveals a point source, called $S1$, in August 2024, detected at S/N $=$ 4-6 (3.3-4.3$\sigma$), a separation of $\approx$1.5" (2 au), and with a F1550C flux (contrast) of $\approx$3.5 mJy ($\approx 5.5 \times 10^{-5}$). Various tests conducted with the data show that $S1$ is unlikely to be a detector or PSF subtraction artifact and confirm that it is neither a background nor a foreground object. $S1$ is not re-detected in the two follow-up observations (February and April 2025). If $S1$ is astrophysical in nature, the only explanation is that it has moved to a region of poor sensitivity due to orbital motion. We perform PSF injection-recovery tests and provide 2D sensitivity maps for each epoch to enable orbital completeness calculations. Additional observations are necessary to re-detect candidate $S1$ and confirm its nature as a planet orbiting our nearest solar-type neighbor.

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arXiv2025

Worlds Next Door: A Candidate Giant Planet Imaged in the Habitable Zone of $\alpha$ Cen A. I. Observations, Orbital and Physical Properties, and Exozodi Upper Limits

We report on coronagraphic observations of the nearest solar-type star, $\alpha$ Cen A, using the MIRI instrument on the James Webb Space Telescope. With three epochs of observation (August 2024, February 2025, and April 2025), we achieve a sensitivity sufficient to detect $T_{\rm eff}\approx$ 225-250 K (1-1.2 $R_{\rm Jup}$) planets between 1"-2" and exozodiacal dust emission at the level of $>$5-8$\times$ the brightness of our own zodiacal cloud. The lack of exozodiacal dust emission sets an unprecedented limit of a few times the brightness of our own zodiacal cloud$-$a factor of $\gtrsim$10 more sensitive than measured toward any other stellar system to date. In August 2024, we detected a F$_\nu$(15.5 $\mu$m) = 3.5 mJy point source, called $S1$, at a separation of 1.5" from $\alpha$ Cen A. Because the August 2024 epoch had only one successful observation at a single roll angle, it is not possible to unambiguously confirm $S1$ as a bona fide planet. Our analysis confirms that $S1$ is neither a background nor a foreground object. $S1$ is not recovered in the February and April 2025 epochs. However, if $S1$ is the counterpart of the object, $C1$, seen by the VLT/NEAR program in 2019, we find that there is a 52% chance that the $S1+C1$ candidate was missed in both follow-up JWST/MIRI observations due to orbital motion. Incorporating constraints from the non-detections, we obtain families of dynamically stable orbits for $S1+C1$ with periods between 2-3 years. These suggest that the planet candidate is on an eccentric ($e \approx 0.4$) orbit significantly inclined with respect to $\alpha$ Cen AB orbital plane ($i_{\rm mutual} \approx 50^\circ$, or $\approx 130^\circ$). Based on the photometry and orbital properties, the planet candidate could have a temperature of 225 K, a radius of $\approx$1-1.1 $R_{\rm Jup}$ and a mass between 90-150 $M_{\rm Earth}$, consistent with RV limits.

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arXiv2025

Size and Shape of Jupiter Trojan (2207) Antenor from Stellar Occultations

Librating around the Lagrange L5, the Jupiter's Trojan (2207) Antenor has been observed in recent years and its rotational light curve suggests it to be a very likely binary asteroid candidate. From stellar occultations, we report results from three events from Europe and North America to estimate the 2D apparent size and shape of Jupiter's Trojan (2207) Antenor. For the best-fitted ellipse in the sky-plane, we determined that Antenor has a 2D apparent equatorial radius of 54.30 +/- 0.99 km at the moment of the occultations, with an apparent oblateness of 0.144 +/- 0.051. We highlight the positive detection from 2021 June 12, which shows an intriguing feature that can be interpreted as a very large topographical feature (of about 11 km) of the body or that can provide further evidence that this object is, in fact, a close or contact binary. We also determine astrometric positions, with uncertainties of a few milliarcseconds (mas) for our preferred solutions.

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arXiv2025

A Terminology and Quantitative Framework for Assessing the Habitability of Solar System and Extraterrestrial Worlds

The search for extraterrestrial life in the Solar System and beyond is a key science driver in astrobiology, planetary science, and astrophysics. A critical step is the identification and characterization of potential habitats, both to guide the search and to interpret its results. However, a well-accepted, self-consistent, flexible, and quantitative terminology and method of assessment of habitability are lacking. Our paper fills this gap based on a three year-long study by the NExSS Quantitative Habitability Science Working Group. We reviewed past studies of habitability, but find that the lack of a universally valid definition of life prohibits a universally applicable definition of habitability. A more nuanced approach is needed. We introduce a quantitative habitability assessment framework (QHF) that enables self-consistent, probabilistic assessment of the compatibility of two models: First, a habitat model, which describes the probability distributions of key conditions in the habitat. Second, a viability model, which describes the probability that a metabolism is viable given a set of environmental conditions. We provide an open-source implementation of this framework and four examples as a proof of concept: (a) Comparison of two exoplanets for observational target prioritization; (b) Interpretation of atmospheric O2 detection in two exoplanets; (c) Subsurface habitability of Mars; and (d) Ocean habitability in Europa. These examples demonstrate that our framework can self-consistently inform astrobiology research over a broad range of questions. The proposed framework is modular so that future work can expand the range and complexity of models available, both for habitats and for metabolisms.

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arXiv2025

NIRCam yells at cloud: JWST MIRI imaging can directly detect exoplanets of the same temperature, mass, age, and orbital separation as Saturn and Jupiter

NIRCam and MIRI coronagraphy have successfully demonstrated the ability to directly image young sub-Jupiter mass and mature gas-giant exoplanets. However, these modes struggle to reach the sensitivities needed to find the population of cold giant planets that are similar to our own Solar System's giant planets ($T_{\rm eff} = 60 - 125$ K; $a=5 - 30$ AU). For the first time, we explore the high-contrast imaging capabilities of MIRI imaging rather than coronagraphy. Using data from the JWST GO 6122: Cool Kids on the Block program which targets nearby ($<6$ pc) M-dwarfs with NIRCam coronagraphy and MIRI imaging, we demonstrate that 21$\mu$m MIRI imaging can detect planets with the same temperature, mass, age, and orbital separations as Saturn and Jupiter. For systems within 3pc, 21$\mu$m MIRI imaging reaches the sensitivity needed to detect planets colder than Saturn ($<95$ K). NIRCam coronagraphy can achieve similar results only in the unlikely case that a cold giant planet is cloud-free. Motivated by these compelling findings, we extend our analysis to evaluate the measured performance of MIRI F2100W imaging versus NIRCam F444W coronagraphy to 70 pc and conclude that MIRI imaging offers the advantage for systems within 20pc. Microlensing surveys predict an occurrence rate as high as 1 - 2 low-mass giant exoplanets per star, suggesting that JWST MIRI imaging surveys of nearby systems may be poised to uncover a substantial population. This breakthrough enables a path towards the first direct characterization of cold giant exoplanets that are analogous to the solar system giant planets.

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