Physics
Scientific paper
Nov 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010jgre..11500f07c&link_type=abstract
Journal of Geophysical Research, Volume 115, Issue E12, CiteID E00F07
Physics
4
Planetary Sciences: Solid Surface Planets: Impact Phenomena, Cratering (6022, 8136)
Scientific paper
The Mars Exploration Rover Opportunity has discovered four large iron-nickel meteorites that range in size from 50 to 240 kg dispersed over 10 km of Meridiani Planum, Mars. Because these meteorites are covered with hollows that resemble regmaglypts, their surfaces record their ablation through the atmosphere, and they must have landed at speeds below hypervelocity (<2 km s-1) to survive. Slowing massive iron meteorites requires a minimum atmospheric density, which was quantified using a numerical model that integrates the equations of motion for incoming meteoroids through an atmosphere of a given surface density and scale height and records their outcomes as direct (generally hypervelocity impacts that form craters), longer over the horizon and fallback flight paths, and skip outs. The present atmosphere of Mars is sufficient to slow iron meteoroids as large as Block Island (the most massive meteorite) via drag and significant ablation on long flight paths, although for standard distributions of entering meteoroid masses, velocities, and entry angles, such events are rare (0.007% of incoming iron meteoroids). Such events require entry angles of 10°-13°, entry velocities of 6-18 km s-1, and entry masses of 225-710 kg. The absence of large stony meteorites is probably at least partially because they are much weaker and thus broken up into smaller fragments on impact. Although differential drag deceleration on long flight paths could disperse fragments of an entering meteoroid by tens of kilometers, dynamic pressures are too low to break up an iron meteorite, leaving the possibility that they are paired an open question.
Chappelow John E.
Golombek Matthew P.
No associations
LandOfFree
Event and conditions that produced the iron meteorite Block Island on Mars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Event and conditions that produced the iron meteorite Block Island on Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Event and conditions that produced the iron meteorite Block Island on Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1489212