PDA

View Full Version : Distribution of Lunar Craters



Eroica
2004-Oct-26, 03:12 PM
Exploring the Night Sky with Binoculars[/i],]Note the tendency for lunar craters to appear in chains or groups, and also that when one formation breaks into another it is almost always the smaller crater which distorts the larger. The distribution is non-random.
Comments?

Nowhere Man
2004-Oct-26, 03:36 PM
(discaimer: I am not an astronomer.) A chain or group is almost certainly caused by a tidally-disrupted impactor. Larger impactors would simply wipe out smaller craters, while smaller impactors would just deface larger craters.

OTOH, the late, unlamented craterchains had a different idea. (http://www.badastronomy.com/phpBB/viewtopic.php?p=267037&highlight=#267037)

Fred

jt-3d
2004-Oct-26, 10:52 PM
Clearly, the groups are the result straffing runs. Ah those were the days.

MoonToMars
2004-Oct-27, 02:04 AM
Exploring the Night Sky with Binoculars[/i],]Note the tendency for lunar craters to appear in chains or groups, and also that when one formation breaks into another it is almost always the smaller crater which distorts the larger. The distribution is non-random.
Comments?

I don't know, but why would these "crater chains" be created by an alien civ? I mean, what would be the point? They are extremely large rather useless depressions in the ground... lol Other than signaling to other life forms... I also don't know why these craters are so "non-random". One asteroid hits with little or bigger ones behind it, causing a chain. WARNING, WARNING I AM NOT A ASTROGEOLOGIST!

:P

kucharek
2004-Oct-27, 05:52 AM
Exploring the Night Sky with Binoculars[/i],]Note the tendency for lunar craters to appear in chains or groups, and also that when one formation breaks into another it is almost always the smaller crater which distorts the larger. The distribution is non-random.
Comments?

I don't know, but why would these "crater chains" be created by an alien civ? I mean, what would be the point? They are extremely large rather useless depressions in the ground... lol Other than signaling to other life forms... I also don't know why these craters are so "non-random". One asteroid hits with little or bigger ones behind it, causing a chain. WARNING, WARNING I AM NOT A ASTROGEOLOGIST!

:P

Non-random doesn't imply artificiality.

AGN Fuel
2004-Oct-27, 07:10 AM
Non-random doesn't imply artificiality.

If you'll remember, btimsah1 pretty much proved that 'irregular' meant artificial...... :wink: :lol:

Eroica
2004-Oct-27, 11:53 AM
I don't know, but why would these "crater chains" be created by an alien civ?
I presume you're joking, but just in case you're not: no one is suggesting that there is an intelligence at work here.

Unfortunately Moore doesn't elaborate, so I'm not sure if he's suggesting that the non-random arrangement of the craters supports the now-defunct theory that the Moon's craters are of volcanic origin. I suspect that in his younger days, when this theory was still mainstream, he was one of its supporters - and old habits die hard.

Deer Run Observatory
2004-Oct-27, 01:38 PM
There's nothing alien in nature in these crater chains. I have seen images of them. Looks just like a string of impacts that clearly occured at the same time by the condition of the craters.

We've actually seen what causes these. A piece of comet or rock that has been broken up still travels together as a group. Anyone remember comet Shoemaker-Levy 9? The "string of pearls"? Passed to close to Jupiter, got broken up but the fragments remained in a line and impacted Jupiter leaving a line of impact marks in the cloud tops.

No reason to suspect the same thing couldn't happen to a small body as it passed by the earth, is broken up, then ends up hitting the moon leaving the same pattern of impact marks. Big difference between the two, SL-9 was huge compared to the crater chains left on the moon and where the cloud tops of Jupiter are in constant flux and quickly remove any sign of impact, the surface of the moon would remain static unless acted upon by another impact.

Evan
2004-Oct-27, 04:51 PM
The distribution of matter in the universe isn't random, it's chaotic. Big difference. Your heart beats in a chaotic pattern, never exactly the same time between beats. In rich starfield photos I have taken it is common to see apparent alignments of stars in long lines, sometimes almost perfectly straight, sometimes 6, 7 or more with nearly equal spacing. In the photo below you can see a string of stars just above the line I have drawn. This isn't always chance alignment, especially when it is 4 to 6 stars. There are many multiple stars systems and they will usually all be orbiting in a similar plane.

In the case of multiple aligned impact craters not only can an object break up but in the early history of the moon during the bombardments it is likely that there was a lot of junk "traveling together" as a loose agglomeration. It would be easily pulled apart by even a distant pass by another body, far outside Roche's limit.

http://vts.bc.ca/pics/starline1.jpg