Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: MorrisJENSEN on 30/08/2016 13:06:21

Title: Could a passing meteor cause a tsunami?
Post by: MorrisJENSEN on 30/08/2016 13:06:21

Would it be feasible for a meteor to fly so close to Earth that its gravitational pull caused a tidal surge i.e a tsunami? If so, how big / what mass would it need?

I'm researching for a short non fiction story, so we can stretch the facts a little. I need a 100 metre plus wave.

Many thanks

Title: Re: Meteor Fly By
Post by: RD on 30/08/2016 16:13:43

If the comet came within ~2 Earth-diameters it would be torn apart ...
https://en.wikipedia.org/wiki/Roche_limit#Roche_limits_for_selected_examples

To cause a tsunami I think it would have to be much bigger than a comet/meteor.

For that you'd need something the size of the moon passing at ~10 Earth-diameters.

BTW If that happened there would also be earthquakes because of increased body tides (https://en.wikipedia.org/wiki/Earth_tide).

Title: Re: Could a passing meteor cause a tsunami?
Post by: chiralSPO on 30/08/2016 20:25:53

Perhaps there could be a tsunami if the comet or meteorite landed in the ocean...

Title: Re: Could a passing meteor cause a tsunami?
Post by: MorrisJENSEN on 31/08/2016 15:29:07

Great responses, thank you. I guess I'll just have to have Apophis land in the ocean. I didn't want a full scale disaster. The people in my story don't have time to get away. I shall dig out my Sheldon Thinking Cap.

Title: Re: Could a passing meteor cause a tsunami?
Post by: chiralSPO on 31/08/2016 16:41:08

a 100 m tsunami is not a full scale disaster? :-p

For the purposes of your story, does the tsunami need to be caused by an astronomical phenomenon? Or would something more terrestrial, perhaps along the lines of an undersea avalanche suit your purposes?

This article ( http://www.livescience.com/24813-east-coast-tsunamis.html ) details a few possible sources of tsunamis up to a few dozen meters high, and one could imagine some more extreme cases leading to more extreme waves...

Title: Re: Could a passing meteor cause a tsunami?
Post by: MorrisJENSEN on 02/09/2016 14:30:39

I wanted to link in the Apophis connection.