NIRSpec Archives

Spectral maps illustrating the distribution in the band centers, depths, and areas for (top) Europa’s 1.5 µm band (1.48 – 1.74 µm) -- astro-ph.EP

Analog Studies, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Cryobiology, Europa, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Jupiter, Mapping, Geodesy, Cartography, Bathymetry, Status Report, Water/Hycean Worlds & Oceanography

JWST Reveals Spectral Tracers of Recent Surface Modification on Europa

by Keith CowingApril 8, 2025April 8, 2025

Europa has been modified by a variety of geologic processes, exposing internally-derived materials that are heavily irradiated by charged particles trapped in Jupiter’s magnetosphere.

At the left, an enhanced-color image of Neptune from NASA’s Hubble Space Telescope. At the right, that image is combined with data from NASA’s James Webb Space Telescope. The cyan splotches, which represent auroral activity, and white clouds, are data from Webb’s Near-Infrared Spectrograph (NIRSpec), overlayed on top of the full image of the planet from Hubble’s Wide Field Camera 3. - STSCI

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Ice Giant, Icy Worlds, Imaging & Spectroscopy, Neptune, People Of Astrobiology, Press Release, Radiation, Space Weather & Heliophysics

Webb Space Telescope Captures Neptune’s Auroras For First Time

by Keith CowingApril 4, 2025May 12, 2025

For the first time, NASA’s James Webb Space Telescope has captured bright auroral activity on Neptune. Auroras occur when energetic particles, often originating from the Sun, become trapped in a […]

This artist’s concept shows what the isolated planetary-mass object SIMP 0136 could look like based on recent observations from NASA’s James Webb Space Telescope and previous observations from Hubble, Spitzer, and numerous ground-based telescopes. Researchers used Webb’s NIRSpec (Near-Infrared Spectrograph) and MIRI (Mid-Infrared Instrument) to measure subtle changes in the brightness of infrared light as the object completed two 2.4-hour rotations. -- NASA, ESA, CSA, and Joseph Olmsted (STScI)

Astronomy & Telescopes, Atmospheres, Climate, Weather, Brown Dwarfs, Exoplanets, -moons, -comets, Gas Giants, Icy Worlds, Imaging & Spectroscopy, Press Release

Webb Exposes Complex Atmosphere of Free-Floating Super-Jupiter SIMP 0136

by Keith CowingMarch 4, 2025March 4, 2025

An international team of researchers has discovered that previously observed variations in brightness of a free-floating planetary-mass object known as SIMP 0136 must be the result of a complex combination […]

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. […]

A simplified diagram of the KPIC phase II instrument including the FIU and FEU. All moving mechanisms are denoted with double ended arrows. The options for each mechanism are listed next to them. The options highlighted in orange are the default settings used for nominal K band science operations most similar to the original phase I mode. The green options are alternative settings available for the many phase II modes. -- astro-ph.IM

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

Technical Description and Performance of the Phase II Version of the Keck Planet Imager and Characterizer

by Keith CowingFebruary 6, 2025February 6, 2025

The Keck Planet Imager and Characterizer (KPIC) is a series of upgrades for the Keck II Adaptive Optics (AO) system and the NIRSPEC spectrograph to enable diffraction limited, high resolution […]

Irregular satellite orbital inclinations and semimajor axes (normalized to Jupiter’s Hill radius). Family groupings are given as indicated. The prograde population is dominated in mass and number by the Himalia family. The retrograde population is categorized into three orbital families, with the more widely dispersed Pasiphae and Ananke families and the more tightly grouped Carme family. This work studies the Himalia, Carme, Pasiphae, and Ananke families, as well as the isolated satellite Themisto. Orbital parameters from JPL Horizons. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Jupiter, Meteorites & Asteroids, Status Report

JWST Reveals Varied Origins Between Jupiter’s Irregular Satellites

by Keith CowingFebruary 5, 2025February 5, 2025

We report observations of eight Jovian irregular satellites with JWST’s NIRSpec instrument: Himalia, Elara, Pasiphae, Sinope, Lysithea, Carme, Ananke, and Themisto. Irregular satellite families, which are presumed to have formed […]

Best fits for the cloud extinction models once their retrievals are finished. Observational data are shown as black/grey dots with error bars. -- astro-ph.EP

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

The Role of Cloud Particle Properties on WASP-39b Transmission Spectrum Based on JWST/NIRSpec Observations

by Keith CowingFebruary 3, 2025February 2, 2025

Aerosols are capable of having a huge influence on reflected, emitted and transmitted planetary spectra. The Near InfraRed Spectrograph (NIRSpec) using the PRISM mode on board of the James Webb […]

Illustration of the planet at orbital quadrature (phase 1.25) and the red/blue shifted velocity and day/night components. At this phase, the planet is red-shifted from the orbital velocity, the dayside emission of the planet is blueshifted from winds and rotation while the fainter night-side is redshifted from winds and rotation. -- astro-ph.EP

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

An Absolute Mass, Precise Age, and Hints of Planetary Winds for WASP-121 A and b From a JWST NIRSpec Phase Curve

by Keith CowingJanuary 8, 2025January 8, 2025

We have conducted a planetary radial velocity measurement of the ultra-hot Jupiter WASP-121b using JWST NIRSpec phase curve data. Our analysis reveals the Doppler shift of the planetary spectral lines […]

The spectral decomposition of the Reference case retrieval of WASP-166b with the absorption contributions of the key atmospheric constituents shown. Spectra are plotted with resolution R = 100 for clarity. The combined forward model, shown as a heavy black line, is the median Reference retrieval result (see Table 5). The colored lines correspond to the individual opacity/absorption contributions (including Rayleigh scattering and collision absorption) of the various constituent molecules and clouds at specific wavelengths. (H2S is plotted but is not distinguishable from the bulk species line.) The transmission spectrum is dominated by contributions from H2O (15.2σ), and CO2 (14.7σ). The more subtle effects of NH3 (2.3σ) may be apparent at ∼ 2.3 µm, and possibly at ∼ 3.9 µm. The effects of the cloud deck (flat purple line at transit depth of ∼ 0.274 x10−2 ) are apparent in clipping the troughs of the water features from 0.85 to 1.7 µm -- astro-ph.EP

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

Detection of H2O and CO2 in the Atmosphere of the Hot Super-Neptune WASP-166b with JWST

by Keith CowingJanuary 3, 2025January 3, 2025

We characterize the atmosphere of the hot super-Neptune WASP-166b (P=5.44 d, Rp=6.9±0.3 R⊕, Mp=32.1±1.6 M⊕, Teq=1270±30 K) orbiting an F9V star using JWST transmission spectroscopy observations obtained with NIRISS SOSS […]

(a) Modeled image from a Monte Carlo dust model for µm-size grains accelerated by outgassing water from 358P, using an active South pole, ε = 80◦ , and Φ = 245◦ , covering the inner 1500×1500 km of the coma as seen from JWST. Intensities in the model image indicate column density, where representative contours are shown as cyan lines. NIRCam F200W contours from Figure 6 are shown in white for comparison. (b) The same as (a), but for Φ = 260◦ as found by Moreno et al. (2013). -- astro-ph.EP

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

The Volatile Composition and Activity Evolution of Main-Belt Comet 358P/PANSTARRS

by Keith CowingNovember 14, 2024November 14, 2024

We report the detection of water vapor associated with main-belt comet 358P/PANSTARRS on UT 2024 January 8-9 using the NIRSPEC instrument aboard JWST.

NIRSpec

JWST Reveals Spectral Tracers of Recent Surface Modification on Europa

Webb Space Telescope Captures Neptune’s Auroras For First Time

Webb Exposes Complex Atmosphere of Free-Floating Super-Jupiter SIMP 0136

Webb Reveals The Ancient Surfaces of Trans-Neptunian Objects

Technical Description and Performance of the Phase II Version of the Keck Planet Imager and Characterizer

JWST Reveals Varied Origins Between Jupiter’s Irregular Satellites

The Role of Cloud Particle Properties on WASP-39b Transmission Spectrum Based on JWST/NIRSpec Observations

An Absolute Mass, Precise Age, and Hints of Planetary Winds for WASP-121 A and b From a JWST NIRSpec Phase Curve

Detection of H2O and CO2 in the Atmosphere of the Hot Super-Neptune WASP-166b with JWST

The Volatile Composition and Activity Evolution of Main-Belt Comet 358P/PANSTARRS

5 Questions About Astrobiology’s Future At NASA

The First Decade of Breakthrough Listen

Mars’ Oddest Cloud May Be Even Odder Than We Thought

A Technosignature Survey Of The Anti-Solar Point: The SETI Institute’s Largest-Ever Campaign With The Allen Telescope Array

Complex Organic Molecules in Protostars with ALMA Spectral Surveys (COMPASS) II. Approach To Data Reduction And Products For Line-rich Broadband (sub)millimeter Spectra