Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: neilep on 09/02/2025 16:38:57

Title: Why Are Craters MOSTLY Round ?
Post by: neilep on 09/02/2025 16:38:57

Dear Cratologists, (I bet every time you see a pothole you just have to pull over and go examine it yes ?)




So Why Are Craters Mostly Round ? Not just moon craters but craters on Earth and other planets too.


(https://lh3.googleusercontent.com/pw/AP1GczPHBKlgk4zSiEq8wblU3l3t85poHrSl8w4FDqDCE_ZZstL2qwJBEO2NqCkEjaI9ZdOELjPl_1ULIp5bq1ggNL5hgCLFZhNYI7q-2iWnG2uBgR4M5Arm=w2400)

Surely the crater-makers don't plop straight down vertically do they ?




whajafink ?




Sheepy
Executive Officer In Charge Of Asking About Round Craters

Title: Re: Why Are Craters MOSTLY Round ?
Post by: Janus on 09/02/2025 16:49:36

The bodies striking are moving so fast when they hit that they have huge amounts of kinetic energy, this vaporizes a good part of the surface they hit, resulting in an explosion much like a bomb. It is this explosion that forms the crater.

Title: Re: Why Are Craters MOSTLY Round ?
Post by: neilep on 09/02/2025 19:16:24

Quote from: Janus on 09/02/2025 16:49:36

The bodies striking are moving so fast when they hit that they have huge amounts of kinetic energy, this vaporizes a good part of the surface they hit, resulting in an explosion much like a bomb. It is this explosion that forms the crater.

ahhhhhh..that explains it. Even I can understand that. Thank you Janus very much 👍

Title: Re: Why Are Craters MOSTLY Round ?
Post by: evan_au on 10/02/2025 02:23:35

Some craters are elliptical in shape, but they are only noticeably elliptical if the impact angle is < 15 degrees. The majority impact at an angle of 16-90 degrees.
- The biggest elliptical crater on the Moon is the south pole-Aitken basin, which is not readily visible from Earth.
https://en.wikipedia.org/wiki/South_Pole%E2%80%93Aitken_basin
- There is a chain of small elliptical craters on the Moon, perhaps created by an asteroid which was tidally disrupted when approaching the Moon(?)
 https://www.planetary.org/space-images/moon-elliptical-crater-chain-lroc

Outside the central impact crater, some asteroid impacts are star-shaped, where rocks were blasted out in radial lines away from the impact site, leaving a star-shaped pattern, like the Tycho crater on the Moon.

Tycho_Crater_Moon.jpg (317.95 kB . 1060x878 - viewed 596 times)