Talk:Meteorites

Broken citation

The reference to astroengine.net gives me error 404 when logged in and a request for user name and password when not logged in.--Farred 15:34, 26 February 2010 (UTC)

Do not exaggerate the meteor danger

A two millimeter meteoroid is a deadly bullet on Earth's moon, but not on Mars.

Scale height for Mars = about 11 km (See: SCALE HEIGHTS AND MARS PRESSURE TRANSDUCER ERRORS) but it varies with temperature.

On Earth the scale height is 8.5 km at 17 C, 8.0 km at 0 C, 7.6 km at - 13 C.

Meteoroids start burning up from atmospheric friction at about 80 km on Earth, where the pressure is about 1 E-4 atmospheres or about 100th the atmospheric density for the surface of Mars. So meteoroids would start burning up at about 50 km altitude on Mars. My guess is that a 4 millimeter meteorite would bounce off a space suit of a person on Mars. A two centimeter diameter meteoroid would be somewhat diminished in size and greatly slowed by the time it hit the Martian surface. My guess is that a solar heated greenhouse would have to sit on Mars for a hundred million years before a meteor would smash it to rubble in one blow. In the mean time replacement of broken glass panes should handle the meteoroid problem without any regolith shielding. An emergency glass repair robot should be able to function even as the ambient pressure goes down. The plants might not even die.

So far there has been no evidence of any of the Mars rovers being hit by a meteorite. - Farred 21:39, 18 October 2013 (UTC)

Discussion: The meteorites in this table are tiny, and even Mars' thin atmosphere would stop them. It is suggested that the table be expanded to include larger bodies. How large must a meteor be before it has a good chance of not breaking up / evaporating by Mars' atmosphere?

<Michel> Well there are now a number of visual impacts and the Insight seismometer measured some of them. but still nothing on the rovers. James Webb did get hit, but it's a tiny impact.

The table is the table of surface impacts, not of total meteorites. These is bound to be an equation behind this table, and as the meteorites get larger the probabilities get very small. The included calculation does propose a significant, but not overwhelming, risk.