This crater situated on the far side of the moon is a very interesting one, since it is partially filled by mare basalt in a hemisphere that is almost completely dominated highland areas. Its basin is filled with mare with a peak situated at the centre. This crater is associated with impact melt and ejecta deposits (figure 1) and FeO rich basaltic mare (figure 2). The latter information has been derived from the Clementine lunar spectral data. Tsiolkovskiy crater is very similar to the lava filled Plato Crater on the near side of the moon.
Estimating the age of the mare region
Data from LRO suggests an age for the mare area that is younger than 3.5 +/- 0.1 Ga.
Vectorisation of primary mare craters that are representative of the age of the basalt mare was carried out using Cratertools embedded in ArcGIS for a chosen area situated in the southern part of the mare basin. Identification of the craters was done using the 100m pixel resolution of LRO WAC mosaic of Tsiolkovskiy. During the vectorisation process, secondary craters were omitted as much as possible from being included in the database.
The total vectorised area was circa 1.12x10^3 km^2. The goal of this vectorisation was to obtain a surface age and have as many craters as possible included in the fit.
Based on the number of craters on the floor of Tsiolkovskiy Crater, the preliminary crater counts presented here suggest that the mare fill in this Crater is between 2.27 ± 0.32 Ga (figure 3). The age of the mare does not directly place an age of the crater itself, which must be much older than this estimate. This can be derived from the analysis of the impact ejecta and melt deposits on the outside of T Crater.
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| Figure 3. Cumulative crater frequency plot of Tsiolkovskiy mare. Created using the Craterstats. |