Using the James Webb Space Telescope to Find Carbon Dioxide on Ganymede

Abstract: The aim of this bachelor's thesis is to search for CO₂ on Ganymede by studyingobservations taken by the James Webb Space Telescope and in doing so, create aprocessing pipeline for JWST data. The data is collected by JWST's Near InfraredSpectrograph instrument which is used for spectroscopy in the near infrared spectrum. Theobservations used for the data in this report were collected with NIRSpec's Integral FieldUnit, along with the grating/filter combination G395H/F290LP, which covers the absorptionband of CO₂ at 4.27 μm. So far there have been two observations of Ganymede in thismode: one of the leading hemisphere and the other of the trailing hemisphere. Band depthanalysis was performed using the absorption spectra of both hemispheres, which gave anestimate of both how much CO₂ is present as well as where it can be found on the surface.Due to the difficulties in finding a reference spectrum for the Sun in the desired wavelengthband, it was instead decided that the JWST observations of the solar analogue GSPC P330-E would suffice. The results of the band depth analysis indicate that CO₂ can be found ingreater concentrations around the equator, while relatively little occurs towards the poles;this is consistent with prior research. Over the course of this project multiple issues withusing JWST data were found and tools and procedures for working around them wereestablished.