Philolaus

D=71 km
Center: 72¡N, 327¡E

Count Area: 196 km^2 (NAC used: M1103744085 L and R)
Observed Density (@ 1km): not observed
Age:  ±  (+sec: )
Stoffler epoch: 
Fit Density (@ 1km):  ± 
PF fit: 

Age calculation notes:


USGS geology: 
Copernican

Wilhelms: 
Copernican

Floor material: 
Best guess is original. Has hummocky and smooth areas, which are likely melt. Peak is sharp.

Geology Observations: 
Near another large, fresh crater Anaxagoras. Ejecta blanket visible, but no bright rays, although can see it's secondary field. Large, sharp central peak complex. Rim sharp. Zoomed out there are linear features that appear to be secondary chains, however, on closer examination in NAC they appear to be collapse pit chains (some have steep walls with irregular rims and they spread in all directions). Individual pits mostly smaller than D=100m cutoff. If secondaries are present they are smaller than my D=100m cutoff. I have some craters labeled as "secondaries", but in this case that just represents craters of unusual morphology. These are typically fresher craters that have morphologies like "splash" or "concentric" or "mound" craters. Instead of being self secondaries, because they are surrounded by similar sized craters that are much more degraded so couldn't have formed when melt was still molten, could likely be due to sensing layered materials.

SFD Observations: 
Dominated by classes 3 and 2. Class 1 at much lower density. All have very similar shapes. Steeper distribution. Slope(Diff)=3.8 ± 0.1.

Using data from McEwen et al. (1993)
Area: ?
Density (@ 1km): 800
Age: 0.9 Ga

Neukum & Konig also have a density = 450 (ejecta)


Last Edited by MRK 1/9/2014