Meteorite Fall Direction?

[Machineman]

Are meteorite more likely to fall in a certain direction, due to earth rotation? Therefore being more common on east facing slopes?

[GotAU?]

Interesting question- you’d think it was possible that the east facing slopes of mountains would rake up more impacts as most meteorite impact speeds are about 400mph after air braking through the atmosphere, and as the Earth’s surface moves eastwards at around 700-1000 mph in North America (depending on latitude), mountains and steep hills would act like a windshield vs bugs and raindrops. I guess the main thing is there’s not really much difference between 400mph and 700–1000mph, when you compare it with the speed that the Earth is revolving around the sun. At 65,000mph, I’d bet it’s the entire leading edge of the Earth, at the time of impact, that rakes up most of the meteorites.

[Bedrock Bob]

On 1/18/2026 at 8:27 PM, Machineman said:

Are meteorite more likely to fall in a certain direction, due to earth rotation? Therefore being more common on east facing slopes?

No. 

They come from all directions and fall in a parabolic arc. Most are falling pretty much vertically by the time they hit the ground. 

The direction they came from defines the long dimension of the strewn field. They detonate and break up high in the atmosphere and the pieces spread out (think shotgun pellets). They travel in "dark flight" for a very long way before falling (almost) vertically to the ground. The cluster (if there is one) of material will lie (theoretically) in an oval shape with the long axis in the direction of flight.

The earth's rotational speed may affect how high the bolide occurs, but once the speed has decayed below terminal velocity they fall along the same parabolic arc. No matter which way they are coming from they are falling pretty much vertically by the time they impact.

Topography in the fall area certainly makes a difference but the spin of the earth won't make more meteorites land on the eastern slopes.

A strong wind during a fall would put as much angle on the material as the direction of entry.

...at least that is the way I understand it.

[GotAU?]

On 2/8/2026 at 5:34 PM, Bedrock Bob said:

No. 

They come from all directions and fall in a parabolic arc. Most are falling pretty much vertically by the time they hit the ground. 

The direction they came from defines the long dimension of the strewn field. They detonate and break up high in the atmosphere and the pieces spread out (think shotgun pellets). They travel in "dark flight" for a very long way before falling (almost) vertically to the ground. The cluster (if there is one) of material will lie (theoretically) in an oval shape with the long axis in the direction of flight.

The earth's rotational speed may affect how high the bolide occurs, but once the speed has decayed below terminal velocity they fall along the same parabolic arc. No matter which way they are coming from they are falling pretty much vertically by the time they impact.

Topography in the fall area certainly makes a difference but the spin of the earth won't make more meteorites land on the eastern slopes.

A strong wind during a fall would put as much angle on the material as the direction of entry.

...at least that is the way I understand it.

Hey Bob, some of the online photos of the impacts from that 2022 Salt Lake meteorite show like there’s some directionality to the impacts based on how the salt crust splattered. The photos are easy to search for on Google, but here’s an example:

[Bedrock Bob]

Surely there is an angle at impact. Much of it is dictated by entry angle. Some by weather. A lot by aerodynamic instability (an odd shaped projectile flies in crazy nutated spirals. A more aerodynamic piece may fly much farther and more stable).

An object coming in at a low angle has a lot of atmosphere to penetrate. Let's say it blows up into a million pieces of various sizes and makes a cloud of debris that has made it to terminal velocity without being blown to dust or less. It flies a "few" miles in dark flight. The decay in speed causes a drop in trajectory. The end of the arc at impact is pretty steep. Not straight down but not coming in sideways either. 

In most terrain that's not enough angle to create much of a "shadow" behind peaks where material didn't fall. I'm sure there are plenty of exceptions to that assumption.

All that means exactly squat. Meteorites fall where they do at the angle they did. We are just discussing the likelihood of a cloud of impacts being greater on one side of a mountain than the other.

My (completely uneducated) opinion is "no" on the earth's rotation question, and "probably not" unless you are hunting extremely vertical territory. 

----

In Glorieta it was often so steep you couldn't stand on the slopes. And there are cliffs a couple hundred feet high. Yes, the terrain made a big difference. Entry angle definitely came into play. The slopes facing (not east) were definitely the best. 

Thats an extreme case though. It's 9,000 feet above sea level in vertical canyons in a rocky mountain pass. In most fall areas the topography and entry angle (probably) wouldn't make (as) much difference.

A meteorite that hit the base of Glorieta peak would still have almost 2 miles to fall at sea level. That's going to make a big difference in trajectory and impact angle compared to "most" places at "most" altitudes.

Just my ramblings based on my limited knowledge and scant personal experience. I could be way off base. Take anything I say about it with doubt and skepticism. I am just another crackpot on the internet that pretends to know all the answers about stuff falling from the sky.