Demise of Kreutz Sungrazing Comet C/2024 S1 (ATLAS)

Summary

Kreutz sungrazing comet C/2024 S1 was observed from ground- and space-based telescopes, revealing a nucleus radius of <600m, disintegration at 0.7 au pre-perihelion, and non-equilibrium mass loss.

Highlights

• Comet C/2024 S1 was discovered a month before perihelion, allowing for physical observations.
• The nucleus radius was found to be <600m with a red geometric albedo of 0.04.
• Disintegration of the nucleus was observed at 0.7 au pre-perihelion.
• The comet's brightness varied unpredictably with distance.
• Peak brightness was reached near 0.075 au, where the radiative temperature is ∼1000 K.
• The comet faded on the way to perihelion, possibly due to grain sublimation.
• Rotational instability caused by outgassing torques is the most efficient mechanism of destruction.

Key Insights

• The comet's nucleus was likely destroyed due to rotational instability caused by outgassing torques, which is a common fate for small Kreutz comets.
• The observed disintegration of the nucleus at 0.7 au pre-perihelion suggests that the comet was experiencing significant mass loss.
• The comet's brightness variations were not simply dependent on heliocentric distance, indicating non-equilibrium mass loss.
• The peak brightness near 0.075 au and subsequent fading may be attributed to grain sublimation, which occurs when the radiative temperature reaches ∼1000 K.
• The comet's small size and low density made it susceptible to rotational disruption and ablative destruction.
• The study highlights the importance of early detection and observation of Kreutz comets to understand their physical nature and decay.
• The findings provide insights into the physical processes that govern the behavior of small, sungrazing comets.

Mindmap

Citation

Jewitt, D., Luu, J., & Li, J. (2024). Demise of Kreutz Sungrazing Comet C/2024 S1 (ATLAS) (Version 1). arXiv. https://doi.org/10.48550/ARXIV.2412.18039