55 Cancri e Archives - Astrobiology

The same gentle wind that would create small ripples on a lake in Earth (right) would make large waves on Saturn’s largest moon Titan (left). In these renderings, the marker is measured in meters. Credit Courtesy of Taylor Perron, Una Schneck, et al

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Icy Worlds, Mars, Press Release, Titan, Water/Hycean Worlds & Oceanography

Waves Hit Different On Other Planets

by Keith CowingApril 20, 2026April 20, 2026

On a calm day, a light breeze might barely ripple the surface of a lake on Earth. But on Saturn’s largest moon Titan, a similar mild wind would kick up […]

Grid of simulations of atmospheric pressure contribution (bars) and total volume mixing ratio (VMR) for each molecular species as a result of initial volatile abundances. Results are shown for the current age of the system and assume no tidal heating (e = 0). Small black dots denote the simulation grid points. Top Left: CO2 atmospheric pressure (bars). Top Center: H2O atmospheric pressure (bars). Top Right: O2 atmospheric pressure (bars). Bottom Left: CO2 VMR. Bottom Center: H2O VMR. Bottom Right: O2 VMR. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Status Report

The Effect of Tidal Heating and Volatile Budgets on the Outgassed Atmosphere of 55 Cancri e

by Keith CowingFebruary 5, 2026February 5, 2026

55 Cancri e is a ∼8 Gyr rocky world (1.95 R⊕, 8.8 M⊕) orbiting a K-type star. JWST observations suggest a carbon-dominated atmosphere (CO2/CO) over a global magma ocean (>3000 […]

The black spectrum represents the best-fitting total emission spectrum of 55 Cancri e from our results.

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Status Report

Characterising the Atmosphere of 55 Cancri e: 1D Forward Model Grid for Current and Future JWST Observations

by Keith CowingMarch 26, 2025

Recent JWST observations with NIRCam and MIRI of the ultra-short-period super-Earth 55 Cancri e indicate a possible volatile atmosphere surrounding the planet. Previous analysis of the NIRCam spectra suggested potential […]

Key elements in the magma temperature-cloud feedback that drives the oscillations in cloudiness and surface temperature. Changes in the color of the magma ocean surface indicate variations in surface temperature (brighter denotes higher temperature). Changes in the brightness of the clouds represent variations in the shortwave opacity of the cloud (brighter denotes higher optical depth). The thicknesses of downward yellow rays indicate shortwave radiation before and after being attenuated by the clouds. The thicknesses of the blue arrows in the upper-right direction indicate ascending vapor fluxes. -- astro-ph.EP

Astrogeology, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Lava / magma ocean / Volcanic Worlds, Status Report

Extreme Weather Variability on Hot Rocky Exoplanet 55 Cancri e Explained by Magma Temperature-Cloud Feedback

by Keith CowingSeptember 26, 2024September 26, 2024

Observations of the ultra-short period rocky exoplanet 55 Cancri e (55 Cnc e) indicate that the planet’s dayside infrared radiation fluctuates by a factor of at least six on sub-weekly […]

Mass - radius relations of puffy Venuses. a: M-R relations compared to observed exoplanets. The grey line is the M-R for terrestrial planets with an Earth-like core mass fraction of 0.325 (Plotnykov & Valencia 2020). Colored solid lines are puffy Venus radii assuming different Teq, with the fiducial, OC-like volatile C and H abundances. The orange dashed line is the M-R for Teq = 2000 K planets with a convective deep atmosphere to the MO surface, instead of a deep radiative zone. The shaded region is the range of M-R space an air-less rocky world can occupy for all possible Fe/Si ∈ [0, 1]. Planets less dense than this region require a volatile component. Measured exoplanet samples are from the NASA Exoplanet Archive (2023), and only contain those with relative errors below 30%. The nine planets highlighted with black circles are our preferred puffy Venus candidates. In rising mass order, they are GJ 1252 b, TOI-500 b, TOI-561 b, Kepler-10 b, Kepler-36 b, HD 219134 b, HD 3167 b, WASP-47 e, and 55 Cnc e. TOI-561 b’s radius is from Patel et al. (2023); its mass is from Brinkman et al. (2023) b: M-R of puffy Venuses with a range of chondritic C abundances, more opaque lines correspond to less C. They are color-coded by temperature - Teq = 1000 K (blue) and 2000 K (orange). The dashed orange line is for wet CI composition, while the solid line with the same color is for dry CI composition. The dotted portion of dry CI, 1000 K line are atmospheres that should experience graphite precipitation; see text. c: M-R of models assuming different chemical scenarios - I (solid), local chemical equilibrium throughout the atmosphere, II (dash-dot), chemical equilibrium at the MO surface, and a CO2 + H2O atmosphere (dotted). Fiducial OC C and H abundances are used. Same color-coding as b. The solid 1000 K and 2000 K lines in a, the 2 OC lines in b, and the 2 Scenario I lines in c are the same. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Lava / magma ocean / Volcanic Worlds, Status Report, Venus

Puffy Venuses: the Mass-Radius Impact of Carbon-Rich Atmospheres on Lava Worlds

by Keith CowingMay 16, 2024May 16, 2024

The recent advancements in exoplanet observations enable the potential detection of exo-Venuses, rocky planets with carbon-rich atmospheres. How extended these atmospheres can be, given high carbon abundances, has not been […]

Self-consistent atmosphere models of 55 Cnc e. The NIRCam relative eclipse depths are offset to a mean depth of 60 ppm. Previous Spitzer measurements 24 are shown in gray. The black dashed lines are blackbody models at the temperatures indicated in the plot. The vaporized-rock model was simulated using the rocky composition that corresponds to the bulk silicate Earth; using other plausible rock compositions results in qualitatively similar results (Extended Data Fig. 7). The atmosphere models are simulated either in a parameter exploration of CHONSP elemental abundances or with the assumption of volatile equilibrium with an underlying magma ocean. The models shown are selected from those that provide adequate fits to the data. The volatile atmosphere models with enhanced outgassing of rock-forming elements can cause substantial changes in the eclipse depth and the emission spectra. The models are smoothed to R=100 for the clarity of illustration. Model results binned to the same wavelength channels as the MIRI data are shown as colored points. The oxygen fugacity (fO2 ) describes the redox condition of the magma and fO2=IW-4 means a condition more reduced than the iron-wustite (IW) buffer by 4 orders of magnitude. The full sets of atmospheric models are described in Methods and Extended Data Figs. 8 and 9. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Status Report

A Secondary Atmosphere On The Rocky Exoplanet 55 Cancri e

by Keith CowingMay 11, 2024

Characterizing rocky exoplanets is a central endeavor of astronomy, and yet the search for atmospheres on rocky exoplanets has hitherto resulted in either tight upper limits on the atmospheric mass […]

This artist’s concept shows what the exoplanet 55 Cancri e could look like. Observations by NASA’s Webb telescope suggest it may be surrounded by an atmosphere rich in carbon dioxide or carbon monoxide, which could have bubbled up from of an ocean of magma on the planet’s surface. Credit: NASA, ESA, CSA, Ralf Crawford (STScI)

Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

Webb Hints At A Possible Atmosphere Surrounding Rocky Exoplanet 55 Cancri e

by Keith CowingMay 8, 2024May 8, 2024

While the planet is too hot to be habitable, detecting its atmosphere could provide insights into the early conditions of Earth, Venus, and Mars.

55 Cancri e

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

The Transient Outgassed Atmosphere of 55 Cancri e

by Keith CowingAugust 14, 2023August 14, 2023

The enigmatic nature of 55 Cancri e has defied theoretical explanation. Any explanation needs to account for the observed variability of its secondary eclipse depth, which is at times consistent […]

Mantle temperature field and velocity field of superEarth 55 Cancri e for the reference model. High velocities (larger than three times the mean mantle velocity) are plotted with a red arrow. The magma ocean is indicated in red (fully molten) and orange (partially molten). -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Status Report

Interior Dynamics Of Super-Earth 55 Cancri e

by Keith CowingAugust 3, 2023May 11, 2024

The ultra-short-period super-Earth 55 Cancri e has a measured radius of 1.8 Earth radii. Previous thermal phase curve observations suggest a strong temperature contrast between the dayside and nightside of […]

Simulated emission spectra of TRAPPIST-1 c with MIRI photometric filter mean fluxes for water and CO2 atmospheres, obtained with the high-resolution, k-correlated MSEIRADTRAN model. Color boxes indicate the wavelength ranges of the different filters. — astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report, TRAPPIST-1

Interior-atmosphere Modelling To Assess The Observability Of Rocky Planets With JWST

by Keith CowingMay 3, 2023May 3, 2023

Super-Earths present compositions dominated by refractory materials. However, there is a degeneracy in their interior structure between a planet with no atmosphere and a small Fe content, and a planet […]