James Webb makes its first observations of Mars

Mars NIRCam images. Images and info courtesy of NASA

The James Webb Space Telescope (JWST) has made its first observations of the planet Mars, complimenting data given by other projects on the red planet with its infrared data.

From its unique observation point, Webb is able to view a region of Mars' southern hemisphere with its Near Infrared Camera (NIRCam) and Near Infrared Spectrograph (NIRSpec) instruments. However, due to Mars being one of the brightest objects in the night sky, Webb could only take very short exposure images of the surface due to the instruments being made to amplify distant light sources.

The first image (upper right), taken at 2.1 microns, showcases many surface details consistent with those in visual images of Mars due to the large amount of relfected sunlight.

The second image (bottom right), taken at 4.3 microns, showcases the thermal emissions given off as Mars loses heat within the region. However, the Hellas Basin, Mars' largest impact crater, appears darker not due to a colder temperature but due to its low altitude and high absorption of CO2 molecules passing through the atmosphere.

Mars NIRSpec data. Graph courtesy of NASA.

Webb's NIRSpec data reveals the composition of Mars' atmosphere by tracking the amount of light absorbed by molecules within it, represented by dips/spikes in the graph. 

Scientists hope to utilize both complete sets of data to explain regional differences on Mars as well as locate trace gasses in the atmosphere.

Webb's position and progress can be tracked on NASA's "Where is Webb?" page.