dwarf planet Archives

(left) This zoomed-in image of Uranus, captured by Webb’s Near-Infrared Camera (NIRCam) Feb. 6, 2023. The planet displays a blue hue in this representative-color image, made by combining data from two filters (F140M, F300M) at 1.4 and 3.0 microns, which are shown here as blue and orange, respectively.(right) Webb’s Near-Infrared Camera (NIRCam) image of Neptune, taken on July 12, 2022, brings the planet’s rings into full focus for the first time in more than three decades. -- NASA/STSCI

Astrogeology, Atmospheres, Climate, Weather, Ice Giant, Magnetic Fields, Electromagnetism, bioelectricity,, Neptune, Press Release, Uranus

Uranus And Neptune Might Be Rock Giants

by Keith CowingDecember 10, 2025December 10, 2025

The planets in the Solar System are typically divided into three categories based on their composition: the four terrestrial rocky planets (Mercury, Venus, Earth and Mars), followed by the two […]

This illustration depicts the interior of dwarf planet Ceres, including the transfer of water and gases from the rocky core to a reservoir of salty water as a consequence of internal heating. NASA ID: PIA26570 larger image

Astrogeology, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Ceres, Habitable Zones, Icy Worlds, Missions & Hardware, Status Report, Water/Hycean Worlds & Oceanography

Fluid Flow In Ceres Due To Core Heating

by Keith CowingOctober 10, 2025October 10, 2025

A couple examples of molecules carrying chemical energy – carbon dioxide and methane – are included in the illustration.

An SwRI-led team used Webb telescope observations (white) to detect methane gas on the distant dwarf planet Makemake. Sharp emission peaks near 3.3 microns reveal methane in the gas phase above Makemake’s surface. A continuum model (cyan) is overlaid for comparison; the gas emission peaks are identified where the observed spectrum rises above the continuum. An artistic rendering of Makemake’s surface is shown in the background. Courtesy of S. Protopapa, I. Wong/SwRI/STScI/NASA/ESA/CSA

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Press Release

Methane Gas Discovered On Makemake

by Keith CowingSeptember 11, 2025

A Southwest Research Institute-led team has reported the first detection of gas on the distant dwarf planet Makemake, using NASA’s James Webb Space Telescope (JWST). This discovery makes Makemake only […]

Masses and radii of well-constrained small planets (0.2 ≤ Mp ≤ 30 M⊕). This catalog is a subset of the NASA Exoplanet Archive showing planets with consistently measured masses (RV or TTV) and measured radii (transit). The points are color-coded by composition: On the left, as bulk water mass fraction (Aguichine et al. 2021) and on the right, as bulk H2/He mass fraction (Lopez & Fortney 2014). Composition lines are shown for an equilibrium temperature of 500 K; rocky and Earth-like predictions are from Zeng et al. (2016). Bold and labeled circle symbols show planets with published JWST transmission spectra, and bold and labeled star symbols show other published COMPASS targets. TOI-776 c (the subject of this paper) is shown in larger font/symbol. -- astro-ph.EP

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

JWST COMPASS: NIRSpec/G395H Transmission Observations of TOI-776 c, a 2 Rearth [Earth radius] M Dwarf Planet

by Keith CowingMarch 4, 2025March 4, 2025

The atmospheres of planets between the size of Earth and Neptune at short orbital periods have been under intense scrutiny.

Images of the trans-Neptunian objects (TNOs) Pluto [left] and Arrokoth [right], the primary flyby targets of NASA’s New Horizons spacecraft in 2015 and 2019. NASA’s James Webb Space Telescope is capable of obtaining observations for in-depth studies of a wide range of TNOs that both complement, and go beyond what was learned by New Horizons. (Image credits: NASA/SwRI/JHU-APL)

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Cryobiology, Icy Worlds, Imaging & Spectroscopy, Pluto, Status Report

Webb Reveals The Ancient Surfaces of Trans-Neptunian Objects

by Keith CowingFebruary 13, 2025February 13, 2025

Trans-Neptunian objects (TNOs) are icy bodies ranging in size from Pluto and Eris (dwarf planets with diameters of about 1,500 miles) down to tens of miles (Arrokoth) and even smaller. […]

Spectrally red-sloped sites on Ceres identified by the deep neural network. Steep red-sloped spectra (organic-rich) are shown in/as red boxes. Yellow boxes indicate locations of moderately red-sloped pixels, which except for Vinotonus do not display the ∼3.4 micron organic feature. Occator red-sloped material is not marked because of its different nature (see text). A blue rectangle outlines an area overlapping Urvara and Yalode, where carbonate-rich materials are exposed. The exact locations of the identified reddish material are marked by small light-green boxes. The area bounded within the blue rectangle is referred to as the “Urvara-Yalode” region. See Figure 9 and Figure S9 in Supporting Information S1 for more details on these sites. Background image is the equirectangular global mosaic of Ceres created using ∼130 m/pix High Altitude Mapping Orbit color data (R-965 nm; G-749 nm; B-438 nm). -- AGU Advances

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Ceres, Cryobiology, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Missions & Hardware, Press Release

Dwarf Planet Ceres: Building Blocks Of Life Delivered From Space

by Keith CowingJanuary 28, 2025January 28, 2025

Organic molecules are among the necessary inventory of life-friendly worlds. On Earth, the compounds of carbon, hydrogen and – in smaller quantities – other elements form the basic building blocks […]

Map of the AOs on Ceres, using as a proxy the 3.4-μm band depth (scale bar) derived by the Dawn VIR data, superimposed to a context map of the Ernutet region. The inset shows an example of a spectrum of aliphatic-rich pixels compared with an average spectrum of the Ernutet region taken by the VIR spectrometer. -- Science via PubMed

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Ceres, Status Report

Recent Replenishment Of Aliphatic Organics On Ceres From A Large Subsurface Reservoir

by Keith CowingDecember 6, 2024December 6, 2024

Ceres hosts notable aliphatic-organic concentrations, ranging from approximately 5 to >30 weight % in specific surface areas.

Time evolution (from left to right) of small grains around Makemake under the influence of solar radiation pressure. -- astro-ph.EP

Astrochemistry, Astrogeology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Status Report

Prominent Mid-infrared Excess Of The Dwarf Planet (136472) Makemake Discovered by JWST/MIRI Indicates Ongoing Activity

by Keith CowingOctober 31, 2024October 31, 2024

We report on the discovery of a very prominent mid-infrared (18-25 um) excess associated with the trans-Neptunian dwarf planet (136472) Makemake.

This simulation was run in a uniformly 90% ice crust (Fig. 1a) at the equator and shows total vertical displacement after 1 Gyr of relaxation. The black lines are the initial state of the simulation, and the solid colour shows the final state of the simulation. In this case, the crater has only shallowed by ~70 m from an initial depth of 2,400 m (seen as the solid colour at the centre of the crater slightly offset from the black line), for a relaxation percentage of

Astrogeology, Biogeochemical Cycles & Geobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Ceres, Comets and Asteroids, Cryobiology, Icy Worlds, Imaging & Spectroscopy, Impact events, Status Report, Water/Hycean Worlds & Oceanography

An Ancient And Impure Frozen Ocean On Ceres Implied By Its Ice-rich Crust

by Keith CowingSeptember 30, 2024September 29, 2024

Ceres is a key object in understanding the evolution of small bodies and is the only dwarf planet to have been orbited by a spacecraft, NASA’s Dawn mission.

Irradiation of NaPyr Under Ceres Conditions

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Ceres, Icy Worlds, Imaging & Spectroscopy, Missions & Hardware, Status Report

Photochemical Stability and Reactivity of Sodium Pyruvate: Implications for Organic Analysis on Ceres

by Keith CowingJune 19, 2024June 19, 2024

The dwarf planet Ceres is a high-priority target for future solar system exploration within this decade. This is motivated by the detection of organics by NASA’s Dawn mission as well […]