resurfacing

In astronomy, "resurfacing" refers to the process that creates smoother surfaces on planets by covering or destroying rough topography. This can occur through several mechanisms:

• Thermal effects: Increased temperatures can weaken a planet's crust, causing mountains to sink and crater floors to rise over millions of years.
• Gravitational flow: Material flowing downhill under gravity can fill depressions, gradually raising the surface level. Lava flows from a planet's interior are an example of this.
• Deposition from above: Fragments from impacts (ejecta) or volcanic ash can blanket existing surfaces, obscuring older topography.

These processes are evident on planets like Mercury, where plains are formed by such resurfacing events, often obscuring older features like impact craters.12