Perseverance (2021) and Curiosity (2012) each ejected, among many other things, two tungsten "cruise balance masses" before reaching Mars's atmosphere, each about 70 kg.
Were their impacts on the surface noticeable, either by craters visible from orbiting cameras, or by Insight's seismometer?
Some sizeable fragments should have reached the surface intact:
- Tungsten's melting point is 3700 K, while Perseverance's heat shield encountered at most 2400 K.
- Tungsten is twice as dense as the nickel-iron meteors that penetrate even Earth's atmosphere.
They would hit the surface at a speed not much less than the approach speed of 5 km/s; the full 70 kg would pack a wallop of almost a gigajoule, about half of "the kinetic energy of a Airbus A380 at cruising speed" per Jalopnik.
Seismometers recorded on 2007 Sept 15 a 17 GJ meteorite impact in Peru whose crater was 14 m wide, so it seems plausible that a 1 GJ impact would be both seismographically noticeable (Mars is much more quiescent than Peru) and visible (MRO never ceases to amaze).