JWST Moving Target Observations

JWST can track and observe planets, satellites, and nearly all comets and asteroids more than 1 AU from the Sun.  

On this page

JWST offers the capabilities necessary for observing Solar System ("moving") targets. Imaging and low- and medium-resolution spectroscopy spanning 0.6–28.5 μm provide high sensitivity and spatial resolution, both without interference by Earth's atmosphere. JWST is on a solar orbit near Earth's L2 point, so scheduling is much more flexible and efficient than for HST (which is in a low-Earth orbit). The thermal design of JWST only allows Solar System targets to be observed near quadrature; observations at opposition are not feasible.

Solar System observations with JWST

An overview of JWST's Solar System capabilities and exploration of some possible science applications can be found in Milam et al. (2016) and Norwood et al. (2015). The following list includes links to flyers on some potential science investigations:

  • General: Overview of JWST's capabilities for observations of solar system targets

  • Solar System GTO & ERS programs: Details of all Guaranteed Time Observations (GTO) and Early Release Science (ERS) programs targeting solar system objects
  • Asteroids & near-Earth objects (NEOs): Surface composition, thermal properties

  • Giant planets: Vertical and horizontal cloud structures, global circulation, chemistry and composition, thermodynamics
  • Trans-Neptunian Objects (TNOs): Surface composition, diameter/albedo, colors, binarity
  • Mars: Atmospheric composition, evolution of dust storms and clouds

  • Occultations: Minor bodies, rings, mutual events, serendipitous occultations
  • Rings and small satellites: Discovery and characterization, transient phenomena (ring arcs and spokes), composition

  • Titan: Atmospheric composition, clouds and hazes, surface temperature, surface changes

More detailed examinations of 10 science areas, and a summary of JWST capabilities and operations for moving targets, can be found in a January 2016 special issue of PASP.

Presentation chart packets from JWST workshops and Townhall events at AAS Division of Planetary Sciences meetings are linked here. They cover in considerable detail topics such as using the Astronomer's Proposal Tool (APT) for planning observations, tracking capabilities of the observatory, and processing data in the pipeline. 

Moving target articles


JWST Moving Target Visibility Tool Help


2016, PASP, 128
Special Issue: Innovative Solar System Science with the James Webb Space Telescope

 Milam, S., et al. 2016, PASP, 128
The James Webb Space Telescope’s Plan for Operations and Instrument Capabilities for Observations in the Solar System

Norwood, J., et al. 2015, arXiv
Solar System Observations with the James Webb Space Telescope

Solar system science flyer



Latest updates
    Updated broken links. Added new links to new and updated 2-page flyer.

    Added link to the Moving Target Visibility Tool (MTVT).