# Observing M Dwarfs UV and optical flares from a CubeSat and their implications for exoplanets habitability

**Authors:** Julien Poyatos, Octavi Fors, José Maria Gómez Cama  
**arXiv:** [2302.12566](https://arxiv.org/abs/2302.12566)  
**Date:** 2023-02-24  
**Summary page:** https://www.summarizepaper.com/en/paper/2302.12566v1/

## Key points

- Exoplanets and their potential habitability are a major focus in astronomy
- M dwarfs are particularly interesting due to their high rocky planet occurrence within the Habitable Zone
- M dwarfs are known for their frequent and powerful flaring, which can have both positive and negative effects on exoplanet habitability
- Increased flux during flare events can trigger chemical reactions necessary for prebiotic chemistry
- Strong flares may erode exoplanet atmospheres and reduce their UV protection
- Flaring flux can be up to 100 times stronger in UV than in the optical, making UV observations crucial for understanding both prebiotic abiogenesis and atmospheric erosion
- A CubeSat payload concept is being developed to complement current flare surveys operating in the optical, which will observe a high number of flaring M dwarfs using an all-sky scanning law coverage in both the UV and optical wavelengths
- After-the-flare follow-up optical ground-based time-resolved spectroscopy will be conducted triggered by detection of UV flares from space on board the proposed CubeSat
- The study of M dwarfs' stellar activity in the UV band will provide useful data for larger forthcoming missions that will survey exoplanets such as PLATO, ARIEL, HabEx, and LUVOIR
- The CubeSat will operate following an all-sky scanning law and a heliosynchronous orbit with a revisit time of two days
- An exposure time of 90 seconds and processing time of 30 seconds means that a science image will be obtained every two minutes
- Results from simulations show that all flares from Group 1 give an SNR >10 dB and are therefore considered observable; however this group contains drastically fewer targets than the other three groups so results may be influenced by poor statistics bias
- The amount of flares of a given energy over time is determined by the FFD (Flare Frequency Distribution), with Groups 3 and 4 representing nearly 95% of the targets in the first four groups
- Overall this CubeSat mission will provide valuable data for understanding M dwarf flaring activity and its impact on exoplanet habitability; it will complement current ground-based surveys while paving the way for future missions to survey exoplanets in more detail.

## Summary

The study of exoplanets and their potential habitability has become a major focus in astronomy, with M dwarfs being particularly interesting due to their high rocky planet occurrence within the Habitable Zone. However, these stars are also known for their frequent and powerful flaring, which can have both positive and negative effects on exoplanet habitability. On one hand, increased flux during flare events can trigger chemical reactions necessary for prebiotic chemistry. On the other hand, strong flares may erode exoplanet atmospheres and reduce their UV protection. Recent observations have shown that flaring flux can be up to 100 times stronger in UV than in the optical, making UV observations crucial for understanding both prebiotic abiogenesis and atmospheric erosion. To address this need for more comprehensive observations of M dwarf flares, a CubeSat payload concept is being developed to complement current flare surveys operating in the optical. This CubeSat will observe a high number of flaring M dwarfs using an all-sky scanning law coverage in both the UV and optical wavelengths to better understand different effective temperatures as wavelengths and flaring status go. Additionally, after-the-flare follow-up optical ground-based time-resolved spectroscopy will be conducted triggered by detection of UV flares from space on board the proposed CubeSat. The study of M dwarfs' stellar activity in the UV band will provide useful data for larger forthcoming missions that will survey exoplanets such as PLATO, ARIEL, HabEx, and LUVOIR. The CubeSat will operate following an all-sky scanning law and a heliosynchronous orbit with a revisit time of two days. An exposure time of 90 seconds and processing time of 30 seconds means that a science image will be obtained every two minutes. Results from simulations show that all flares from Group 1 give an SNR >10 dB and are therefore considered observable; however this group contains drastically fewer targets than the other three groups so results may be influenced by poor statistics bias. The amount of flares of a given energy over time is determined by the FFD (Flare Frequency Distribution), with Groups 3 and 4 representing nearly 95% of the targets in the first four groups. Overall this CubeSat mission will provide valuable data for understanding M dwarf flaring activity and its impact on exoplanet habitability; it will complement current ground-based surveys while paving the way for future missions to survey exoplanets in more detail.