How Does InSight Distinguish Marsquakes from Meteor Impacts?

[RJ Emery]

Every day the Earth is bombarded with meteors both large and small, most disintegrating in the atmosphere. A few strike the surface. Mars has no significant atmosphere. Thus, how is the marsquake signal detected by the InSight Lander distinguished from a true marsquake versus a meteor impact somewhere else on the Martian surface?

http://www.sci-news.com/space/insight-first-marsquake-07122.html

 

[Drakkith]

Good question. I assume the signals from an impact event are different from geologic activity, but I'd like to know as well.

 

[berkeman]

Agreed. That may take some help from @davenn and others...

 

[davenn]

Greetings @RJ Emery

Welcome to PF

Every day the Earth is bombarded with meteors both large and small, most disintegrating in the atmosphere. A few strike the surface. Mars has no significant atmosphere. Thus, how is the marsquake signal detected by the InSight Lander distinguished from a true marsquake versus a meteor impact somewhere else on the Martian surface?

http://www.sci-news.com/space/insight-first-marsquake-07122.html

This is the good bit from that article ...

“The Sol 128 event is exciting because its size and longer duration fit the profile of moonquakes detected on the lunar surface during NASA’s Apollo missions,” said Dr. Lori Glaze, Planetary Science Division director at NASA Headquarters.

Fortunately NASA/JPL have had many years of experience of recording and analysing moonquakes to determine the differences between
actual quakes and meteorite impacts and because the geology of Mars will be sort of similar to the Moon ...eg. no plate tectonics,
no known current active volcanism or oceans, therefore the types of quakes detected will likely to be quite similar.
Tho there are still unanswered questions

Here is some more info on them from my own www site that I posted so many years ago...
http://www.sydneystormcity.com/moonqk.htm
and a .pdf file with good info...
https://www.lpi.usra.edu/meetings/lpsc2004/pdf/2093.pdf
Basically they discovered differences in the seismic signatures of quakes compared to impacts when analysing the seismogramscheers
Dave

 

[RJ Emery]

The interior compositions of the Moon and Mars are dissimilar. Thus, observational experience with the Moon is not necessarily transferable to Mars. Nevertheless, any impact on the surface sufficiently large to create a planet-wide seismic signature would probably leave a crater, to be eventually detected by the Mars Reconnaissance Orbiter, which is continually searching for surface changes.

 

[davenn]

The interior compositions of the Moon and Mars are dissimilar.

not completely ... they are both thought to be cold ... that single fact makes a big similarity between them

Thus, observational experience with the Moon is not necessarily transferable to Mars.

well, if you read the papers you will find that there are things that are transferrable

Nevertheless, any impact on the surface sufficiently large to create a planet-wide seismic signature would probably leave a crater, to be eventually detected by the Mars Reconnaissance Orbiter, which is continually searching for surface changes.

hmmm, you really didn't read any of the info did you

I gave you some insight into what they saw and you completely dismissed itDave