How different would a comet impact be vs. an asteroid impact?

Question

If a 50 meter asteroid caused a 1.5 kilometer crater as Barringer Crater is described, how different would the impact of a 50 meter comet be, assuming the comet was 85% water and other volatiles, with the solid parts being mostly dust with a pile of gravel or a relatively small solid core? How much of the volatiles would be boiled off on impact with the atmosphere? Would it be enough to distribute the aftermath over a wider area, or would the comet remain basically intact and hit the Earth as an essentially solid mass? Consider also what effect steam explosions at or near the surface of the comet would have, or if a crack in the comet allowed a steam explosion to penetrate deep within it. Would the volatiles boiling off keep the solid matter cool enough so it would survive the fall to the ground? How fast would the meteorites be going if they did hit the ground? Would it perhaps look like an extremely intense meteor shower shortly followed by a scalding deluge? Would a larger area be affected by a solid impact or a cometary one?

So many questions, and "there's more at the door..."

Answer 1

An iron meteor surviving the trip through the atmosphere would loose a huge amount of kinetic energy onto its impact point resulting in well ... a crater. Effects are much more localized.

An icey comet has tons of matter behind it and a shockwave ahead of it. In between would be superheated steam looking for a way out. What usually happens is, like an overheated steam boiler, at some point it explodes. The effects, like at Tunguska, are more widespread with little or no material reaching the ground.