Uranus Archives

Models for Neptune and Uranus derived in this study expressed as density versus radius. Contour colors show density. Key elements of the models are labelled. The bright narrow band at the base of the envelope in each case is the boundary region stable against convection, ∼ 120 km and ∼ 180 km wide in the cases of Neptune and Uranus, respectively. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Ice Giant, Lava / magma ocean / Volcanic Worlds, Neptune, Status Report, Uranus, Water/Hycean Worlds & Oceanography

Ice Giants Revisited: Uranus And Neptune As Magma Ocean Worlds

by Keith CowingJune 18, 2026June 18, 2026

Uranus and Neptune are commonly interpreted as volatile-rich “ice giants”, an assumption that underpins most interior models.

Example Uranus orbit insertion outside the zeta ring. Uranus orbit insertion maneuver traverses Uranus’s ring plane in the epsilon-ν ring gap (left). Uranus orbit insertion (UOI) burn (1.62 hr duration, 1331 m s−1) as viewed from Earth (right). While this example occurs in full view of ground stations, this is not a feature of all UOI geometries, where some portion of the burn is typically occulted with respect to Earth. Uranus’s orbital velocity vector is indicated for reference. Reproduced from D. Ellison et al. (2025).

Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Ice Giant, Imaging & Spectroscopy, Missions & Hardware, Status Report, Uranus

Uranus Orbiter and Probe: Mission Challenges and Concept Updates Since the Origins, Worlds, and Life Decadal Survey

by Keith CowingJune 14, 2026June 14, 2026

Origins, Worlds, and Life: Planetary Science and Astrobiology in the Next Decade identified a Uranus Orbiter and Probe as the highest-priority strategic mission for the decade 2023–2032, as it enables […]

Details of the interior models of Uranus and Neptune. Top: Illustration of the three-layer internal structure model assumed. Both the envelope and mantle contain hydrogen, helium, ices, and rocks, with the mantle expected to have a higher concentration of ices and rocks. The core is composed entirely of rocks. Bottom: Envelope metallicity versus mantle metallicity for interior models of Uranus and Neptune. Each dot represents a model that fits both the gravitational data and radius of the respective planet. The color scale indicates the core mass. -- astro-ph.EP

Astrogeology, Exoplanets, -moons, -comets, Ice Giant, Icy Worlds, Neptune, Status Report, Uranus

Reassessing Planetary Composition: Evidence Of Rock-dominated Envelopes In Uranus And Neptune

by Keith CowingApril 17, 2026April 17, 2026

Although Uranus and Neptune are commonly classified as ice giants, their exact compositions remain poorly constrained. Recent studies of outer Solar System bodies challenge the traditional view that these planets […]

Fully corrected and calibrated albedos of Titan (yellow), Saturn (green), Uranus (blue), and Neptune (red) covering 0.3 µm to 2.1 µm, offset for clarity. Regions of strong telluric absorption are masked in lighter shades, and it should be noted that they are less reliably corrected. The flat regions in the UV were flagged as bad pixels in all images by X-shooter. We also highlight a vertical discontinuity between the VIS and NIR arms of Titan, which is likely due to weather inconsistency. The colors used for these objects are the same in the following figures. -- Astronomy & Astrophysics

Astrochemistry, Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Gas Giants, Ice Giant, Jupiter, Mars, Mercury, Neptune, Saturn, Status Report, Titan, Uranus

HiDef Neighbors: Solar System Objects As Exoplanet Analogs I. Gaseous Objects, Planets, Planetary Systems, And Small Bodies

by Keith CowingMarch 27, 2026

Context. Intermediate-resolution spectral observations are vital tools for characterizing the composition and physical properties of Solar System bodies in detail. At present, the planets and moons of our Solar System […]

The Pale Blue Dot is a photograph of Earth taken Feb. 14, 1990, by NASA’s Voyager 1 at a distance of 3.7 billion miles (6 billion kilometers) from the Sun. The image inspired the title of scientist Carl Sagan's book, "Pale Blue Dot: A Vision of the Human Future in Space," in which he wrote: "Look again at that dot. That's here. That's home. That's us." The above image, “Pale Blue Dot Revisited,” was created in 2020 for the 30th anniversary of the iconic picture. The updated version used modern image-processing software and techniques to revisit the well-known Voyager view, while attempting to respect the original data and intent of those who planned the images. NASA/JPL-Caltech Larger image

Imaging & Spectroscopy, Interstellar, Jupiter, Mars, Mercury, Neptune, Press Release, Uranus, Venus

Pale Blue Dot Anniversary

by Keith CowingFebruary 14, 2026February 14, 2026

The Pale Blue Dot is a photograph of Earth taken on Feb. 14, 1990, by NASA’s Voyager 1 spacecraft. Earth appears as a tiny speck of light suspended in a […]

Outer Planets Assessment Group (OPAG) -- NASA

Conferences and Meetings, Ice Giant, Neptune, Status Report, Uranus

OPAG Town Hall at AGU Fall Meeting 2025: December 18

by Keith CowingDecember 13, 2025December 13, 2025

The Outer Planets Assessment Group (OPAG) will hold a Town Hall at the AGU meeting in New Orleans, LA. Please join us for a community discussion! The steering committee will […]

(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 […]

Astrochemistry, Astrogeology, Exoplanets, -moons, -comets, Ice Giant, Missions & Hardware, Neptune, Status Report, Uranus

Ice Giants Pre-Decadal Survey Mission Study Report

by Keith CowingNovember 20, 2025November 19, 2025

The Ice Giants Study was commissioned by NASA to take a fresh look (as of 2017) at science priorities and concepts for missions to the Uranus and Neptune systems in […]

The four giant planets as seen by Hubble WFC3/UVIS at different near-UV wavelengths, and processed by Judy Schmidt (note - these images are not shown to scale). The Jupiter and Saturn images are constructed from F343N (red), F275W (green), and F225 (blue), whereas a lack of observations for Uranus and Neptune required us to shift to redder wavelengths: F547M (red), F467M (green), and F336W (blue) for the Ice Giants. Jupiter and Ganymede were observed 2017-02-02 at 12:16UT, Saturn was observed at 2018-06-07 at 00:06UT, Uranus on 2015-08-30 at 10:08UT, and Neptune on 2015-09-02 at 07:58UT. Strong UV absorption is visible at the poles of Jupiter and Saturn due to the nature of highaltitude aerosols and the potential link to auroral chemistry. Red vortices, such as Jupiter’s Great Red Spot and Oval BA (lower left), appear dark due to the blue-absorbing chromophore responsible for their red colours. Uranus’ bright north polar cap of aerosols, and its narrow rings, are just visible in this image. Neptune’s banding, and some bright high clouds (appearing in pink) can be seen in both northern and southern hemispheres. In addition, Saturn’s rings appear reddish due to UV absorption. Credit: NASA/ESA/CSA/Hubble/Judy Schmidt.

Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gas Giants, Ice Giant, Imaging & Spectroscopy, Jupiter, Neptune, Saturn, Status Report, Uranus

Exploring Giant Planet Atmospheres with Habitable Worlds Observatory

by Keith CowingOctober 22, 2025October 22, 2025

Visible and ultraviolet imaging and spectroscopy of Solar System giant planets can set the paradigm for the atmospheric, ionospheric, and magnetospheric processes shaping the diversity of giant exoplanets, brown dwarfs, […]

Reprocessed images of Uranus [L]] and Neptune [R] NASA/JPL-Caltech (Uranus and Neptune); “Modelling the Seasonal Cycle of Uranus’s Colour and Magnitude, and Comparison with Neptune,” by Patrick G. J. Irwin et al., in Monthly Notices of the Royal Astronomical Society, Vol. 527, No. 4; February 2024 (reprocessed images)

Astrogeology, Exoplanets, -moons, -comets, Ice Giant, Icy Worlds, Neptune, Status Report, Uranus

Icy or Rocky? Convective Or Stable? New Interior Models Of Uranus and Neptune

by Keith CowingOctober 3, 2025October 3, 2025

We present a new framework for constructing agnostic and yet physical models for planetary interiors and apply it to Uranus and Neptune.

Uranus

Ice Giants Revisited: Uranus And Neptune As Magma Ocean Worlds

Uranus Orbiter and Probe: Mission Challenges and Concept Updates Since the Origins, Worlds, and Life Decadal Survey

Reassessing Planetary Composition: Evidence Of Rock-dominated Envelopes In Uranus And Neptune

HiDef Neighbors: Solar System Objects As Exoplanet Analogs I. Gaseous Objects, Planets, Planetary Systems, And Small Bodies

Pale Blue Dot Anniversary

OPAG Town Hall at AGU Fall Meeting 2025: December 18

Uranus And Neptune Might Be Rock Giants

Ice Giants Pre-Decadal Survey Mission Study Report

Exploring Giant Planet Atmospheres with Habitable Worlds Observatory

Icy or Rocky? Convective Or Stable? New Interior Models Of Uranus and Neptune

PJ Harvey Announces New Song “Voyager”

Fifty Years after Viking: The Promise of Solar System Microbiology and Microbial Ecology

Characterising Transiting Exoplanets At Long Orbital Period: Lessons Learned For PLATO From 10 Years Of Monitoring The HIP41378 System

Implications Of Self-consistent H2O Ice Optical Constants On Radiative Transfer Models Of Disks

The GAPS Programme at TNG LXXIV. A Reanalysis Of The Planetary Systems TOI-1272 And TOI-1694 With HARPS-N And Retraction Of The Planetary Interpretation Of TOI-1272 c