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James Webb Space Telescope
Solar System

JWST Solar System Scientists

New PASP Special Issue Papers (and Science Flyers)
Innovative Solar System Science with the James Webb Space Telescope
Stefanie Milam, Ed.
Published in PASP v128, Jan. 2016

TITLE and astro-ph link Lead Author Science Flyer
The James Webb Space Telescope’s Plan for Operations and Instrument Capabilities for Observations in the Solar System S.N. Milam et al. Observations in the Solar System
Observing Near-Earth Objects with the James Webb Space Telescope C.A. Thomas et al. Observations of Asteroids and NEOs
Asteroids and JWST A.S. Rivkin
Unique Spectroscopy and Imaging of Mars with JWST G. Villanueva et al. Observations of Mars
Giant Planet Observations with the James Webb Space Telescope J. Norwood et al. Observations of the Giant Planets
Observing Outer Planet Satellites (except Titan) with JWST: Science Justification and Observational Requirements L. Keszthelyi et al. Coming Soon
Titan Science with the James Webb Space Telescope (JWST) C.A. Nixon et al. Observations of Titan
Observing Planetary Rings and Small Satellites with JWST: Science Justification and Observation Requirements M.S. Tiscareno Observations of Rings
Cometary Science with the James Webb Space Telescope M.S.P. Kelley et al. Coming Soon
Physical Characterization of TNOs with JWST A. Parker et al. Coming Soon
JWST Observations of Stellar Occultations by Solar System Bodies and Rings P. Santos-Sanz et al. Coming Soon

Solar System Observations with the James Webb Space Telescope
J. Norwood et al.
Published in PASP v128, February 2016


The James Webb Space Telescope will enable a wealth of new scientific investigations in the near- and mid-infrared, with sensitivity and spatial/spectral resolution greatly surpassing its predecessors. In this paper, we focus upon Solar System science facilitated by JWST, discussing the most current information available concerning JWST instrument properties and observing techniques relevant to planetary science. We also present numerous example observing scenarios for a wide variety of Solar System targets to illustrate the potential of JWST science to the Solar System community. This paper updates and supersedes the Solar System white paper published by the JWST Project in 2010 (Lunine et al., 2010). It is based both on that paper and on a workshop held at the annual meeting of the Division for Planetary Sciences in Reno, NV in 2012.

Other Solar System Science Flyers and Documents

A number of science investigations are currently underway. The preliminary finding on these studies were presented during a workshop on the Sunday prior to the 46th Annual Division for Planetary Sciences Meeting in Tucson on November 9, 2014. JWST Solar System science case flyers are available, as well as the FAQ sheet.

Other presentations regarding Solar System observations with JWST including an Observatory overview, Operations Concept for Moving Targets,, and Asteroid Science with JWST are available.

2015 Division for Planetary Science (DPS) Meeting

The 47th Annual AAS Division for Planetary Science meeting was held at the National Harbor in Washington, DC on 8-13 November 2015. This meeting hosts hundreds of planetary scientist from around the world annually to discuss exceptional science in the field. JWST was highlighted during multiple events including: A newsworthy townhall with presentations from John Mather, Stefanie Milam, and John Stansberry on the latest status, new proposed science, and overview of the mission. Additionally, JWST participated in a full day workshop on NASA Planetary Science and Astrophysics Assests Workshop, which is summarized with details for each mission. Finally, tours were offered to participants to see flight hardware in the cleanroom at NASA's Goddard Space Flight Center. A webcam is available to everyone to follow along with the telescope's progress.

Workshops and Town Hall events on Solar System Science with JWST

Click here to see presentations/documents from these meetings.




History of Planetary Science With Observatories Like Hubble And Spitzer

NASA's flagship observatories have provided many successes in Solar System exploration. These missions, like Hubble and Spitzer, have directly led to new discoveries and also enhanced the productivity of planetary missions. For example, monitoring of Mars has led to insights on ideal landing sites for Martian missions, and discoveries near Pluto have provided course corrections and science targets for New Horizons. Among the many discoveries are:

  • Discovery of new moons around Pluto
  • Discovery of the largest ring around Saturn
  • Characterization of Ceres, Vesta, and other dwarf planets and asteroids
  • Discovery of new Kuiper Belt Objects (KBOs)
  • Detailed studies of cloud structure in outer gas giants
  • Long-term monitoring of the Martian atmosphere
  • Characterizing new classes of objects: Main Belt Comets or "active asteroids"

The New Capabilities Provided by JWST

JWST is ~100 times more powerful than the Hubble and Spitzer observatories. It has greater sensitivity, higher spatial resolution in the infrared, and significantly higher spectral resolution in the mid infrared.

Moons of the Solar System
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JWST observations of solar system objects, including targets of opportunity (ToO), are expected to constitute a significant fraction of the total observing time.

JWST Quick Facts

Example Solar System Science with JWST

Kuiper Belt Objects (KBOs)

Kuiper Belt Objects
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Imaging and spectroscopy observations can be used to:

  • determine diameters and albedos for a large sample of KBOs;
  • search for evidence of collisionally–induced changes in albedo;
  • make near–simultaneous measurements to mitigate rotational.

Spectroscopy will directly constrain surface composition (H2O, CH4, CH3OH) and volatile inventories of known KBOs, and provide the first spectra of many of these objects at 2.5–5 microns. The ice/water hydration band at 3.1 microns is easily within the reach of JWST's NIRSpec instrument in the vast majority of KBOs. Such results will directly address the dynamical (and chemical) history of the solar system and test formation theories. The observations will also elucidate the role that giant planet migration has played in the evolution of the solar system. Radiometry of KBOs will enable better characterization of their albedos and hence the size distribution within the Kuiper Belt.

Dwarf Planets

Dwarf Planets
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Imaging and spectroscopy observations can be used to:

  • determine the physical state of the ices and the composition of the organics;
  • make detailed studies of the composition to determine what molecules are present on their surfaces (and in their atmospheres), and map the distribution of the constituents vs. longitude.
  • provide the first detection of the low-temperature phase of solid N2, and determine whether N2 is present at all on Eris (where there is only indirect evidence for it).
  • determine the thermal state of the surface using thermal light-curves for the brighter objects, and to measure the mid-IR thermal emission for the first time for the fainter objects with the JWST MIRI instrument.


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JWST observations can provide:

  • near-infrared spectroscopy with R = 1000 of cometary comae;
  • mid infrared spectroscopy of cometary dust grains;
  • the first spectroscopic studies of the new class of icy comets in the main asteroid belt.

JWST will enable studies of the chemical composition of cometary ice and dust with unprecedented sensitivity. Spectroscopy will measure abundances of H2O, CO2, CO, and CH3OH in the comae of faint comets and also constrain the ratio of ortho and para H2O to reveal formation temperatures. This set of observations is a critical ingredient in understanding planetary system formation and evolution, when combined with synergistic JWST observations of circumstellar disks. Additionally, the study of icy comets in the asteroid belt may reveal the source objects that were responsible for the delivery of water to the Earth.

Planets and Moons

Io and Jupiter
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JWST observations can:

  • provide time-resolved near-infrared spectroscopy to study the variability of atmospheric species including CO2, CO, and H2O and constrain radiative and absorptive properties of airborn dust, enabling photochemical and dynamical modeling of the Martian climate;
  • provide direct near-infrared detection to assess magnitude and scale of diurnal, seasonal, and interannual volatile transport, and discriminate surface and atmospheric ices and clouds;
  • enable constraints to be placed on potential methane outbursts.
Jupiter and Saturn

JWST observations can:

  • provide mid infrared medium resolution spectroscopy and IFU data to study the rich atmosphere compositions;
  • fully explore infrared diagnostics such as phosphine and methane flourescence, which link to vertical dynamics and thermal structure of the upper atmosphere;
  • provide a global context on large-scale weather patterns for high-resolution studies from complementary planetary missions (e.g., Juno and Cassini).
Uranus and Neptune

JWST observations can:

  • image clouds structures;
  • provide high sensitivity maps of chemical species at high latitudes;
  • perform spectral characterization of H3+, CO in flourescence, detailed mapping within the 5 micron window, search for minor species, and measure isotopic ratios of major elements;
  • provide mid infrared observations to measure temporal variations in temperature, resolve sources of underlying driving dynamics, and disentangle causes of rotation modulation.
Icy Moons

JWST observations can:

  • complement and extend planetary missions such as Cassini.
  • perform long-time baseline observations of both atmospheric and surface changes.
  • provide near-IR spectrometry for Titan with a six-times greater spectral resolution than Cassini to determine types of organic species present on the surface — the higher spectral resolution over mid-latitude regions will reveal whether surface changes or secular atmospheric changes are in evidence over a decade timescale.