Results 61 to 70 of about 757 (177)

The Compositions of the HR 8799 Planets Reflect Accretion of Both Solids and Metal-enriched Gas

The Astrophysical Journal
With four giant planets ( m  ∼ 5 M _Jup −10 M _Jup , T _eff  ∼ 900–1200 K) orbiting between 15 and 70 au, HR 8799 provides an unparalleled test bed for studying giant planet formation and probing compositional trends across the protoplanetary disk.
Jerry W. Xuan, Jean-Baptiste Ruffio, Yayaati Chachan, Kazumasa Ohno, Aurora Kesseli, Ruth Murray-Clay, Eve J. Lee, Julianne I. Moses, William O. Balmer, Aneesh Baburaj, Geoffrey A. Blake, Doug Johnstone, Yapeng Zhang, Heather A. Knutson, Dimitri Mawet, Charles Beichman, Klaus Hodapp, Marshall D. Perrin, Quinn Konopacky, Michael Meyer, Geoffrey Bryden, Thomas P. Greene, Jarron Leisenring, Marie Ygouf, Björn Benneke, Julie Inglis, Nicole L. Wallack   +26 more
doaj   +1 more source

Modeling the Seasonality of Wind‐Driven Hydrocarbon Waves in Titan's Polar Lakes

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract Titan, the only body in the solar system aside from Earth with standing liquids on its surface, has high‐latitude hydrocarbon lakes and seas. As Titan's atmosphere generates light winds, there should be waves on the surface of these lakes and seas, yet, direct wave observations are scant.
Charlene E. Detelich, Una G. Schneck, Alexander G. Hayes, Milan Curcic, Rose V. Palermo, Andrew D. Ashton, J. Taylor Perron, Juan M. Lora, Jordan Steckloff   +8 more
wiley   +1 more source

Volcanism at Piton de la Fournaise as an Analog for Chloris Mons, Venus

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract Identifying and investigating terrestrial analogs for Venus volcanic activity is necessary to prepare for the planned upcoming missions to Venus. We propose volcanism at Piton de la Fournaise, a frequently active oceanic shield volcano, as an analog to volcanism at Chloris Mons, Venus.
Evan G. K. Cooper, Ian T. W. Flynn, Sean I. Peters, Elliott W. Benson, Sara B. Murphy, Eleanor D. Sterling   +5 more
wiley   +1 more source

Impacts of Carbon Dioxide Deposition on Martian Near‐Surface Wave Activity

Geophysical Research Letters, Volume 53, Issue 7, 16 April 2026.
Abstract A prominent feature of Mars' winter atmosphere is near‐surface baroclinic wave activity. These waves exert strong control on dust storm variability and contribute to transport of heat, momentum, and dust. Using a suite of Mars general circulation model simulations, we investigate an underexplored connection between near‐surface wave activity ...
Hung Kwan Fok, Anthony Toigo, Darryn Waugh   +2 more
wiley   +1 more source

Helium Depletion in Escaping Atmospheres of Sub-Neptunes: A Signature of Primary-to-secondary Transition

The Astrophysical Journal
Short-period sub-Neptunes are common in extrasolar systems. These sub-Neptunes are generally thought to have primary atmospheres of protoplanetary-disk gas origin.
Issei Kobayashi, Hiroyuki Kurokawa, Laura Schaefer, Satoshi Okuzumi   +3 more
doaj   +1 more source

A Fast, Parallelized, GPU-accelerated Photochemical Model, XODIAC, with Built-in Equilibrium Chemistry and Multiple Chemical Networks for Exoplanetary Atmospheres

The Astrophysical Journal
The launch of the James Webb Space Telescope has delivered high-quality atmospheric observations and expanded the known chemical inventory of exoplanetary atmospheres, opening new avenues for atmospheric chemistry modeling to interpret these data.
Priyankush Ghosh, Sambit Mishra, Shubham Dey, Debayan Das, P. B. Rimmer, Liton Majumdar   +5 more
doaj   +1 more source

Seasonal Changes in the Atmosphere of HD 80606 b Observed with JWST’s NIRSpec/G395H

The Astronomical Journal
High-eccentricity gas giant planets serve as unique laboratories for studying the thermal and chemical properties of H/He-dominated atmospheres. One of the most extreme cases is HD 80606 b—a hot Jupiter orbiting a Sun-like star with an eccentricity of 0 ...
James T. Sikora, Jason F. Rowe, Jared Splinter, Saugata Barat, Lisa Dang, Nicolas B. Cowan, Thomas Barclay, Knicole D. Colón, Jean-Michel Désert, Stephen R. Kane, Joe Llama, Hinna Shivkumar, Keivan G. Stassun, Elisa V. Quintana   +13 more
doaj   +1 more source

A Metal-poor Atmosphere with a Hot Interior for a Young Sub-Neptune Progenitor: JWST/NIRSpec Transmission Spectrum of V1298 Tau b

The Astronomical Journal
We present the JWST/NIRSpec G395H transmission spectrum of the young (10–30 Myr) transiting planet V1298 Tau b (9.85 ± 0.35 R _⊕ , T _eq  = 670 K). Combined Hubble Space Telescope and JWST observations reveal a haze-free, H/He-dominated atmosphere with a
Saugata Barat, Jean-Michel Désert, Sagnick Mukherjee, Jayesh M. Goyal, Qiao Xue, Yui Kawashima, Allona Vazan, William Misener, Hilke E. Schlichting, Jonathan J. Fortney, Jacob L. Bean, Swaroop Avarsekar, Gregory W. Henry, Robin Baeyens, Michael R. Line, John H. Livingston, Trevor David, Erik A. Petigura, James T. Sikora, Hinna Shivkumar, Adina D. Feinstein, Antonija Oklopčić   +21 more
doaj   +1 more source

The mutual influence of disequilibrium composition and temperature in exoplanet atmospheres

Astronomy & Astrophysics
Astronomical observations have provided an extensive body of evidence for the existence of disequilibrium chemistry in many exoplanet atmospheres, and this departure from a chemical equilibrium composition may have an impact on the temperature of the atmosphere itself.
openaire   +4 more sources

Retrieval of atmospheric structure and composition of exoplanets from transit spectroscopy

, 2012
Recent spectroscopic observations of transiting exoplanets have permitted the derivation of the thermal structure and molecular abundances of H2O, CO, CO2, CH4, metallic oxides and alkali metals in these extreme atmospheres. Here, for the first time, a fully-fledged retrieval algorithm has been applied to exoplanet spectra to determine the thermal ...
openaire   +2 more sources