Results 71 to 80 of about 16,797 (229)

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

Astro2020 Science White Paper: Toward Finding Earth 2.0: Masses and Orbits of Small Planets with Extreme Radial Velocity Precision [PDF]

, 2019
Having discovered that Earth-sized planets are common, we are now embarking on a journey to determine if Earth-like planets are also common. Finding Earth-like planets is one of the most compelling endeavors of the 21st century - leading us toward ...
Bean, Jacob, Burt, Jennifer, Ciardi, David R., Dragomir, Diana, Gaidos, Eric, Johnson, Marshall C., Kempton, Eliza, Konopacky, Quinn, Meyer, Michael, Teske, Johanna, Weiss, Lauren, Zhou, George   +11 more
core   +1 more source

Theoretical Spectra of Terrestrial Exoplanet Surfaces [PDF]

, 2012
We investigate spectra of airless rocky exoplanets with a theoretical framework that self-consistently treats reflection and thermal emission. We find that a silicate surface on an exoplanet is spectroscopically detectable via prominent Si-O features in ...
Batalha, Best, Bethany L. Ehlmann, Borucki, Borucki, Cheek, Clark, Clark, Cochran, Cowan, de Pater, Drilling, Farmer, Gautier, Koch, Miller-Ricci, Muirhead, Pieters, Pieters, RELAB Spectral Database, Renyu Hu, Rogers, Salisbury, Sara Seager, Seager, Seager, Sobolev, Sprague, Winn   +28 more
core   +2 more sources

On the relative importance of AGN winds for the evolution of exoplanet atmospheres

Monthly Notices of the Royal Astronomical Society, 2022
ABSTRACT Recent work investigating the impact of winds and outflows from active galactic nuclei (AGNs) on the habitability of exoplanets suggests that such activity could be deleterious for the long-term survival of planetary atmospheres and the habitability of planets subject to such winds.
openaire   +2 more sources

Early evolution of purple retinal pigments on Earth and implications for exoplanet biosignatures [PDF]

International Journal of Astrobiology, 2018
AbstractWe propose that retinal-based phototrophy arose early in the evolution of life on Earth, profoundly impacting the development of photosynthesis and creating implications for the search for life beyond our planet. While the early evolutionary history of phototrophy is largely in the realm of the unknown, the onset of oxygenic photosynthesis in ...
DasSarma, Shiladitya, Schwieterman, Edward W   +1 more
openaire   +7 more sources

Survey and Modeling of Windblown Ejecta Deposits on Venus

AGU Advances, Volume 6, Issue 5, October 2025.
Abstract Venus' thick atmosphere rotates in the same direction as the solid body, but ∼60 times faster. This atmospheric superrotation has produced dozens of windblown ejecta deposits (“parabolas”) on the surface of Venus. The formation and modification of parabolas is an interplay between impacts, aeolian modification, and atmospheric dynamics.
T. J. Austin, J. G. O’Rourke, N. Izenberg, E. A. Silber   +3 more
wiley   +1 more source

The Not-so Dramatic Effect of Advective Flows on Gas Accretion

The Astrophysical Journal
Super-Earths and mini-Neptunes are the most common types of exoplanets discovered, yet the physics of their formation are still debated. Standard core accretion models in gas-rich environments find that typical mini-Neptune mass planets would blow up ...
Vincent Savignac, Eve J. Lee
doaj   +1 more source

Astrobiology and astrophilosophy: subsuming or bifurcating diciplines? [PDF]

, 2019
Initially, astrobiology subsumed into philosophy. However, philosophy has increasingly subsumed into astrobiology concurrent with it steadily becoming an observational and experimental activity that mainly focuses on the link between life and the cosmos,
von Hegner, Ian
core  

Galactic chemical evolution of the solar neighbourhood, solar twins, and exoplanet indicators [PDF]

, 2022
Charles R. Cowley, Kutluay Yüce
openalex   +1 more source

Evidence for a Natural Limit to Electron Space Radiation: An Application of Benford's Law

Journal of Geophysical Research: Space Physics, Volume 130, Issue 10, October 2025.
Abstract Recent research has highlighted observational evidence for a natural limit to the severity of energetic electron differential fluxes in the Van Allen radiation belts. Here, we analyze the occurrence distributions of electron differential fluxes from the entire Van Allen Probes mission (2012–2019) to further investigate the energy dependence of
L. Olifer, I. R. Mann
wiley   +1 more source