New Horizons flyby of Arrokoth reveals how planets are formed

The video discusses two main theories of planet formation: hierarchical accretion, where smaller objects collide at high speeds to form larger structures, and cloud collapse, where matter gently clumps together at low speeds. NASA's New Horizons spacecraft explored the Kuiper Belt and conducted a flyby of the ancient planetesimal Era Cough. Studies published in the Journal of Science analyzed high-resolution photos of Era Cough, revealing no evidence of violent impacts, suggesting a gentle accumulation of matter. Simulations indicate that Era Cough's two parts formed independently from the collapse of the same cloud and eventually merged.

What findings did NASA's New Horizons spacecraft reveal about the ancient planetesimal Era Cough?

Summarize the implications of the studies published in the Journal of Science regarding the formation of Era Cough.