A5040369637- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Atmospheric Ozone and Climate
- Astrophysics and Star Formation Studies
- Planetary Science and Exploration
- Spectroscopy and Laser Applications
- Space Exploration and Technology
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Methane Hydrates and Related Phenomena
- Geophysics and Gravity Measurements
- Space Science and Extraterrestrial Life
- Calibration and Measurement Techniques
- Adaptive optics and wavefront sensing
- Isotope Analysis in Ecology
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Scientific Research and Discoveries
- Spacecraft and Cryogenic Technologies
- Spacecraft Design and Technology
- Atmospheric and Environmental Gas Dynamics
- Spaceflight effects on biology
- Hydrocarbon exploration and reservoir analysis
- Geomagnetism and Paleomagnetism Studies
California Institute of Technology
2016-2025
Yan'an Hospital Affiliated To Kunming Medical University
2025
Anhui University of Traditional Chinese Medicine
2025
Northwest A&F University
2025
Kunming Medical University
2025
Jilin Agricultural University
2024-2025
Jet Propulsion Laboratory
2015-2024
Commercial Aircraft Corporation of China (China)
2021-2024
Austrian Academy of Sciences
2022
University of Central Florida
2022
A key legacy of the recently launched TESS mission will be to provide astronomical community with many best transiting exoplanet targets for atmospheric characterization. However, time is essence take full advantage this opportunity. JWST, although delayed, still complete its nominal five year on a timeline that motivates rapid identification, confirmation, and mass measurement top characterization from TESS. Beyond future dedicated missions studies such as ARIEL require discovery...
We present a comprehensive photochemistry model for exploration of the chemical composition terrestrial exoplanet atmospheres. The is designed from ground up to have capacity treat all types planet atmospheres, ranging oxidizing through reducing, which makes code suitable applications wide range anticipated compositions. one-dimensional transport treats 800 reactions, photochemical processes, dry and wet deposition, surface emission, thermal escape O, H, C, N, S bearing species, as well...
We present a catalog of panchromatic spectral energy distributions (SEDs) for 7 M and 4 K dwarf stars that span X-ray to infrared wavelengths (5 {\AA} - 5.5 {\mu}m). These SEDs are composites Chandra or XMM-Newton data from 5 ~50 {\AA}, plasma emission model 100 broadband empirical estimates 1170 HST 5700 including reconstruction stellar Ly{\alpha} at 1215.67 PHOENIX spectrum 55000 {\AA}. Using these SEDs, we computed the photodissociation rates several molecules prevalent in planetary...
Transmission spectroscopy1-3 of exoplanets has revealed signatures water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble Spitzer Space Telescopes were hindered by observations' relatively narrow wavelength range spectral resolving power, which precluded unambiguous identification other chemical species-in particular primary carbon-bearing molecules6,7. Here we report broad-wavelength 0.5-5.5 µm atmospheric...
Measuring the abundances of carbon and oxygen in exoplanet atmospheres is considered a crucial avenue for unlocking formation evolution exoplanetary systems. Access to an exoplanet's chemical inventory requires high-precision observations, often inferred from individual molecular detections with low-resolution space-based high-resolution ground-based facilities. Here we report medium-resolution (R$\sim$600) transmission spectrum atmosphere between 3-5 $\mu$m covering multiple absorption...
Abstract Carbon dioxide (CO 2 ) is a key chemical species that found in wide range of planetary atmospheres. In the context exoplanets, CO an indicator metal enrichment (that is, elements heavier than helium, also called ‘metallicity’) 1–3 , and thus formation processes primary atmospheres hot gas giants 4–6 . It one most promising to detect secondary terrestrial exoplanets 7–9 Previous photometric measurements transiting planets with Spitzer Space Telescope have given hints presence but not...
Photochemistry is a fundamental process of planetary atmospheres that regulates the atmospheric composition and stability. However, no unambiguous photochemical products have been detected in exoplanet to date. Recent observations from JWST Transiting Exoplanet Early Release Science Program found spectral absorption feature at 4.05 $\mu$m arising SO$_2$ atmosphere WASP-39b. WASP-39b 1.27-Jupiter-radii, Saturn-mass (0.28 M$_J$) gas giant orbiting Sun-like star with an equilibrium temperature...
Abstract Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining dominant chemical processes at work and, if equilibrium, revealing planet formation histories. Transmission spectroscopy (for example, refs. 1,2 ) provides necessary means by abundances of oxygen- carbon-bearing species; however, this requires broad wavelength coverage, moderate spectral resolution high precision, which, together, are not achievable with...
Geological evidence shows that ancient Mars had large volumes of liquid water. Models past hydrogen escape to space, calibrated with observations the current rate, cannot explain present-day deuterium-to-hydrogen isotope ratio (D/H). We simulated volcanic degassing, atmospheric escape, and crustal hydration on Mars, incorporating observational constraints from spacecraft, rovers, meteorites. found water equivalent a 100 1500 meter global layer are simultaneously compatible geological...
Seven rocky planets orbit the nearby dwarf star TRAPPIST-1, providing a unique opportunity to search for atmospheres on small outside Solar System (Gillon et al., 2017). Thanks recent launch of JWST, possible atmospheric constituents such as carbon dioxide (CO2) are now detectable (Morley 2017, Lincowski 2018}. Recent JWST observations innermost planet TRAPPIST-1 b showed that it is most probably bare rock without any CO2 in its atmosphere (Greene 2023). Here we report detection thermal...
The recent inference of sulfur dioxide (SO2) in the atmosphere hot (approximately 1,100 K), Saturn-mass exoplanet WASP-39b from near-infrared JWST observations1-3 suggests that photochemistry is a key process high-temperature atmospheres4. This because low (<1 ppb) abundance SO2 under thermochemical equilibrium compared with produced H2O and H2S (1-10 ppm)4-9. However, was made single, small molecular feature transmission spectrum at 4.05 μm and, therefore, detection other absorption bands...
Abstract Hot Jupiters are among the best-studied exoplanets, but it is still poorly understood how their chemical composition and cloud properties vary with longitude. Theoretical models predict that clouds may condense on nightside molecular abundances can be driven out of equilibrium by zonal winds. Here we report a phase-resolved emission spectrum hot Jupiter WASP-43b measured from 5 μm to 12 JWST’s Mid-Infrared Instrument. The spectra reveal large day–night temperature contrast (with...
Abstract The James Webb Space Telescope (JWST) recently measured the transmission spectrum of K2-18b, a habitable-zone sub-Neptune exoplanet, detecting CH 4 and CO 2 in its atmosphere. discovery paper argued data are best explained by habitable “Hycean” world, consisting relatively thin H -dominated atmosphere overlying liquid water ocean. Here, we use photochemical climate models to simulate K2-18b as both Hycean planet gas-rich mini-Neptune with no defined surface. We find that lifeless...
Abstract We present the mid-infrared (5–12 μ m) phase curve of GJ 367b observed by Mid-Infrared Instrument on James Webb Space Telescope (JWST). is a hot ( T eq = 1370 K), extremely dense (10.2 ± 1.3 g cm −3 ) sub-Earth orbiting an M dwarf 0.32 day orbit. measure eclipse depth 79 4 ppm, nightside planet-to-star flux ratio 8 and relative amplitude 0.97 0.10, all fully consistent with zero-albedo planet no heat recirculation. Such scenario also offset 11°E 5° to within 2.2 σ . The emission...
Abstract LHS 1140 b is a small planet orbiting in the habitable zone of its M4.5V dwarf host. Recent mass and radius constraints have indicated that it has either thick H 2 -rich atmosphere or substantial water by mass. Here we present transmission spectrum between 1.7 5.2 μ m, obtained using NIRSpec instrument on JWST. By combining spectral retrievals self-consistent atmospheric models, show inconsistent with atmospheres varied size metallicity, leaving world as remaining scenario to...
Some super Earths and mini Neptunes will likely have thick atmospheres that are not H2-dominated. We developed a photochemistry–thermochemistry kinetic-transport model for exploring the compositions of on Neptunes, applicable both H2-dominated non-H2-dominated atmospheres. Using this to study wide ranges temperatures elemental abundances, we classify them into hydrogen-rich atmospheres, water-rich oxygen-rich hydrocarbon-rich find carbon has be in form CO2 rather than CH4 or CO H2-depleted...
(Abridged) Super Earth exoplanets are being discovered with increasing frequency and some will be able to retain stable H2-dominated atmospheres. We study biosignature gases on thin H2 atmospheres habitable surface temperatures, by using a model atmosphere photochemistry, biomass estimate framework for evaluating the plausibilty of range gas candidates. find that photochemically produced H atoms most abundant reactive species in In high CO2 levels, atomic O is major destructive molecules....
Sulfur gases are common components in the volcanic and biological emission on Earth, expected to be important input for atmospheres terrestrial exoplanets. We study atmospheric composition spectra of exoplanets with sulfur compounds (i.e., H2S SO2) emitted from their surfaces. use a comprehensive one-dimensional photochemistry model radiative transfer investigate chemistry ranging reducing oxidizing. The most finding is that both SO2 chemically short-lived virtually all types exoplanets,...
Abstract The climate of Mars likely evolved from a warmer, wetter early state to the cold, arid current state. However, no solutions for this evolution have previously been found satisfy observed geological features and isotopic measurements atmosphere. Here we show that family exist, invoking missing reservoirs or loss processes. Escape carbon via CO photodissociation sputtering enriches heavy ( 13 C) in Martian atmosphere, partially compensated by moderate carbonate precipitation....
We investigate spectra of airless rocky exoplanets with a theoretical framework that self-consistently treats reflection and thermal emission. find silicate surface on an exoplanet is spectroscopically detectable via prominent Si–O features in the emission bands 7–13 μm 15–25 μm. The variation brightness temperature due to can be up 20 K for Earth analog, are wide enough distinguished from atmospheric relatively high resolution spectra. characterization thus provides method unambiguously...
Biosignature gas detection is one of the ultimate future goals for exoplanet atmosphere studies. We have created a framework linking biosignature detectability to biomass estimates, including atmospheric photochemistry and biological thermodynamics. The new intended liberate predictive models from requiring fixed, Earth-like source fluxes. New gases can be considered with check that estimate physically plausible. validated on terrestrial production NO, H2S, CH4, CH3Cl, DMS. applied propose...