Messala is a
lunar crater of sufficient dimension to belong to
the category of impact features known as walled plains. It is
located in the northeastern part of the
Moon,
close enough to the rim to appear significantly foreshortened.
Nearly
attached to the northern rim is the crater Schumacher
. To the southwest is the prominent crater
Geminus
, and due
south is the smaller Bernoulli
.
The outer rim of this formation has received a significant amount
of erosion due to minor impacts, but much of the outer wall retains
its original shape and a certain degree of
terracing. The rim is broken by smaller
craters along the south, north, and northwest sides, designated
Messala B, J, and K, respectively. Messala J has a narrow gouge in
its eastern rim leading one crater diameter to the east. It is
attached to a slightly larger crater which lies across the southern
rim of Schumacher.
The interior floor is relatively level but contains irregularities
in the surface at some locations. There are several small craters
across the floor, which are now little more than low rims and
depressions in the surface. The most notable of these is a
ghost crater along the western inner wall.
Satellite craters
By convention these features are identified on lunar maps by
placing the letter on the side of the crater mid-point that is
closest to Messala.
Origin of name
The crater
is named after Masha'allah ibn Atharī
(c.740-d.815 AD), a Persian
Jewish astrologer and
astronomer from the city of Basra
(now located
in modern day Iraq
) who was the
leading astrologer of the late 8th century. Masha'allah was
one of the most prominent members of the commission which
determined for the
Caliph al-Mansur (A.D.
754-775) that the propitious moment for
the founding of Baghdad
fell on 30
July 762
| Messala |
Latitude |
Longitude |
Diameter |
| A |
36.6° N |
53.8° E |
26 km |
| B |
37.4° N |
59.9° E |
18 km |
| C |
40.9° N |
65.8° E |
12 km |
| D |
40.5° N |
67.8° E |
28 km |
| E |
40.0° N |
64.9° E |
40 km |
| F |
38.9° N |
64.4° E |
32 km |
| G |
39.1° N |
68.6° E |
29 km |
| J |
41.1° N |
61.2° E |
15 km |
| K |
41.1° N |
58.5° E |
13 km |
References