Erik Meier Valdés

I'm a Dr!

Huge thanks to the CHEOPS team involved, as well as collaborators who contributed to this work. Personally I enjoyed crafting this paper and hope you enjoy the reading.

CHEOPS high precision observations put a valuable piece in this puzzle called 55 Cancri e!

Recent JWST observations from accepted cycle 1 proposals might shed light into species present in this fascinating exoplanet.

However, quartz, silicon carbide and graphite do survive for hours in the circumstellar environment. But how would they escape a planet with an escape velocity of 24 km/s? 🤔

What was the outcome? Dust made of pyroxenes and olivines, predominant in Earth-like mantles, sublimate in mere seconds. A torus cannot be composed of these material and cause the phase curve variability!

Considering different silicates and species expected in an Earth-like mantle, we estimated the sublimation timescale for a range of grain sizes compatible with past optical and IR observations.

An inhomogeneous circumstellar torus of dust has been a plausible hypothesis in past research over the years, but for the first time we dug deep into the matter.

We had to step into the shoes of Sherlock Holmes and find the culprit. Is it stellar activity? Volcanic activity due to the extreme temperatures? Magnetic star-planet interaction? Presence of inhomogeneous material in the circumstellar environment?

The conclusions after roughly 800 hours of observations: The phase curve amplitude and peak vary in time, even from one visit to the next.
What is causing the variability on this iconic super-Earth?

55 Cancri e has eluded explanations since it was discovered. We know its mass and radius, but its atmosphere (or lack thereof) is a total mystery.
What if we observed 29 full phase curves with CHEOPS to try to dig deeper? Well, we did!

https://arxiv.org/abs/2307.06085