CUTE Satellite

Characterize the composition and mass-loss rates of exoplanet atmospheres.

Use near-ultraviolet (NUV) transmission spectroscopy from 255 to 330 nanometers (nm) to characterize the composition and mass-loss rates of exoplanet atmospheres. CUTE measures how the NUV light from the host star is changed as the exoplanet transits in front of the star and passes through the planet’s atmospheres. CUTE’s spectrally resolved lightcurve will provide constraints on the composition and escape rates of these atmospheres, and may provide the first concrete evidence for magnetic fields on extrasolar planets.

The mission goal is to train and educate students while conducting scientific research. This mission is similar to the CSSWE, MinXSS‐1, MinXSS‐2 and CSIM, which have gathered over 100 MB of data from amateur operators and were coordinated by the IARU. As has been the case in the past, we will be actively soliciting the telemetry from amateurs. The information provided by amateurs has been crucial for past missions, enabling us to detect instrument orbits and the Doppler‐shifted communication frequencies and troubleshoot anomalies. It is common for all of our missions to have extensive student involvement during the design, building, testing, and operation of the instrument.

CUTE captured ~50 scientifically viable transits from 6 exoplanets despite frequent sun-point regressions.

The first NASA-funded small satellite for exoplanet science is continuing to gather data well beyond its expected lifetime. CUTE was designed to operate in space for at least eight months. Twenty-seven months later, the satellite’s onboard instruments still are observing the dramatic atmospheric loss of “hot jupiters,” gas giants orbiting very close to bright stars. CUTE remains operational more than two years after launch thanks to ingenuity and luck.

• Cesium Satellite 1
• Cesium Satellite 2
• CuPID
• CUTE