# A map of the large day-night temperature gradient of a super-Earth exoplanet

**Authors:** Brice-Olivier Demory, Michael Gillon, Julien de Wit, Nikku Madhusudhan, Emeline Bolmont, Kevin Heng, Tiffany Kataria, Nikole Lewis, Renyu Hu, Jessica Krick, Vlada Stamenkovic, Bjorn Benneke, Stephen Kane, Didier Queloz  
**arXiv:** [1604.05725](https://arxiv.org/abs/1604.05725)  
**Date:** 2016-04-19  
**Summary page:** https://www.summarizepaper.com/en/paper/1604.05725v1/

## Key points

- Groundbreaking study published in Nature on atmospheric properties of super-Earth exoplanets
- Detailed observations of transiting super-Earth 55 Cancri e
- Revealed highly asymmetric dayside thermal emission and significant day-night temperature contrast
- Modulation of thermal flux as planet orbited star in tidally locked configuration
- Discovery of hot spot located 41 ± 12 degrees east of substellar point
- Nightside brightness temperature constrained to be 1380 ± 400 kelvin
- Warmest hemisphere centered on hot spot approximately 1300 kelvin hotter at a wavelength of 4.5 microns
- Inefficient heat redistribution from dayside to nightside observed, providing insights into complex dynamics and thermal characteristics of super-Earth exoplanets

## Summary

In a groundbreaking study published in Nature, researchers have provided new insights into the atmospheric properties of super-Earth exoplanets by conducting detailed observations of the nearby transiting super-Earth 55 Cancri e. This research has shed light on the challenges associated with observing smaller planets and has revealed highly asymmetric dayside thermal emission and a significant day-night temperature contrast through dedicated space-based monitoring in the infrared spectrum. The planet's thermal flux exhibited modulation as it orbited its star in a tidally locked configuration, leading to the discovery of a hot spot located 41 ± 12 degrees east of the substellar point. Further analysis of the orbital phase curve allowed researchers to constrain the nightside brightness temperature of 55 Cancri e to be 1380 ± 400 kelvin. Additionally, they found that the warmest hemisphere centered on the hot spot was approximately 1300 kelvin hotter (2700 ± 270 kelvin) at a wavelength of 4.5 microns. This observation suggests inefficient heat redistribution from the dayside to the nightside and provides valuable insights into the complex dynamics and thermal characteristics of super-Earth exoplanets. These findings contribute significantly to our understanding of these intriguing celestial bodies.