Juliet Archives

This rendering demonstrates what is happening during a stellar occultation and illustrates an example of the light curve data graph recorded by scientists that enables them to gather atmospheric measurements, like temperature and pressure, from Uranus as the amount of starlight changes when the planet eclipses the star. NASA/Langley Research Center Advanced Concepts Laboratory Video

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Ice Giant, Icy Worlds, Imaging & Spectroscopy, Press Release, Uranus

Using Stellar Occultation To Study The Atmosphere Of Ice Giant Uranus

by Keith CowingMay 13, 2025

When a planet’s orbit brings it between Earth and a distant star, it’s more than just a cosmic game of hide and seek. It’s an opportunity for NASA to improve […]

JWST NIRCam albedos of Proteus and Puck compared to the spectra of 2004 EW95 (Plutino) and 2007 VL305 (Neptune Trojan) from JWST Programs 2418 and 2550 respectively. Also shown are Voyager-derived visual geometric albedos, with the Puck albedo selected to be at the same phase angle as the JWST observations (see Figure 6 of Karkoschka (2001) and Table 2 of Karkoschka (2003)). The spectrophotometry for Proteus and Puck closely matches the shape and albedo for the selected objects, both of which have less red/neutral spectral slopes, and perihelia also near 30AU. Higher resolution spectra for Puck and Proteus are needed to reveal surface composition. -- astro-ph.EP

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Icy Worlds, Imaging & Spectroscopy, Miranda, Neptune, Oberon, Status Report, Titania, Triton, Umbriel, Uranus

JWST Spectrophotometry of the Small Satellites of Uranus and Neptune

by Keith CowingApril 11, 2024April 11, 2024

We use 1.4-4.6 micron multi-band photometry of the small inner Uranian and Neptunian satellites obtained with the James Webb Space Telescope’s near-infrared imager NIRCam to characterize their surface compositions.