Warm Gas-Giant Exoplanet WASP-107 b Transmission Spectrum (NIRSpec)

 Warm Gas-Giant Exoplanet WASP-107 b Transmission Spectrum (NIRSpec)

This transmission spectrum, captured using Webb’s NIRSpec (Near-Infrared Spectrograph), shows the amounts of different wavelengths (colors) of near-infrared starlight blocked by the atmosphere of the gas-giant exoplanet WASP-107 b.

The spectrum was made by observing the planet-star system for about 8.5 hours before, during, and after the transit as the planet moved across the face of the star.  

By comparing the brightness of light filtered through the planet’s atmosphere (transmitted light) to unfiltered starlight, it is possible to calculate the amount of each wavelength that is blocked by the atmosphere. Since each molecule absorbs a unique combination of wavelengths, the transmission spectrum can be used to constrain the abundance of various gases.

This spectrum shows clear evidence for water (H2O), carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), and sulfur dioxide (SO2) in the planet’s atmosphere, allowing researchers to estimate the interior temperature and mass of the core.



NASA, ESA, CSA, Ralf Crawford (STScI)


David Sing (JHU), NIRSpec GTO Transiting Exoplanet Team

About The Object
Object Name WASP-107 b
Object Description Warm Neptune Exoplanet
R.A. Position 12h33m32.74s 
Dec. Position -10d08m46.37s 
Constellation Virgo
Distance 210 light-years
About The Data
Data Description NIRSpec Bright-Object Time Series Spectroscopy
Instrument NIRSpec
Exposure Dates June 23, 2023
About The Object
Object Name A name or catalog number that astronomers use to identify an astronomical object.
Object Description The type of astronomical object.
R.A. Position Right ascension – analogous to longitude – is one component of an object's position.
Dec. Position Declination – analogous to latitude – is one component of an object's position.
Constellation One of 88 recognized regions of the celestial sphere in which the object appears.
Distance The physical distance from Earth to the astronomical object. Distances within our solar system are usually measured in Astronomical Units (AU). Distances between stars are usually measured in light-years. Interstellar distances can also be measured in parsecs.
Dimensions The physical size of the object or the apparent angle it subtends on the sky.
About The Data
Data Description
  • Proposal: A description of the observations, their scientific justification, and the links to the data available in the science archive.
  • Science Team: The astronomers who planned the observations and analyzed the data. "PI" refers to the Principal Investigator.
Instrument The science instrument used to produce the data.
Exposure Dates The date(s) that the telescope made its observations and the total exposure time.
Filters The camera filters that were used in the science observations.
About The Image
Image Credit The primary individuals and institutions responsible for the content.
Publication Date The date and time the release content became public.
Color Info A brief description of the methods used to convert telescope data into the color image being presented.
Orientation The rotation of the image on the sky with respect to the north pole of the celestial sphere.