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compared to 170 m and 210 m in Fig.
8.22
c, respectively, which is a reasonable
correspondence.
Similarly, the heights of the domes R3 and R4 in the Mons Rümker volcanic
complex according to the DEM shown in Fig.
8.29
b, obtained by Wöhler et al.
(
2007a
) using a telescopic CCD image, correspond to 275 m and 185 m, respec-
tively. The DEM shown in Fig.
8.29
d, constructed based on a SMART-1 AMIE
image (cf. Fig.
8.29
c), yields height values of 240 m and 170 m for R3 and R4,
respectively, indicating a high degree of consistency.
8.4.3.3 Comparison to Other Height Measurements
Not too much topographic data about lunar domes had been published prior to
the studies described in the previous sections. The most significant contribution
to this field has been provided by Brungart (
1964
), who compiled a catalogue of
261 domes reporting their coordinates, diameters, heights, flank slopes, and mor-
phological characteristics, utilising the Orthographic Lunar Atlas (Kuiper,
1961
),
which consists of telescopic photographs. Brungart (
1964
) determines values for
the dome heights and flank slopes based on shadow length measurement but at the
same time characterises the obtained results as merely representing order of mag-
nitude estimates. As an example, for Arago
α
and
β
(entries no. 3 and 4 in the
Brungart catalogue) a height of 700 m and 800 m with an average flank slope of
5
.
5
◦
and 6
.
0
◦
is reported, respectively. Our results indicate lower heights of 330 m
and 270 m along with flank slopes of 1
.
5
◦
and 1
.
3
◦
, respectively. For Milichius
π
(entry no. 190), Brungart (
1964
) states a height of 742 m with an average flank
slope of 9
◦
. An estimate of the height of this dome with the method of Ashbrook
(
1961
) yields an average slope angle of 2
.
7
◦
and a height of 230 m (cf. Table
8.1
),
which is found to be in good agreement with the photoclinometry and shape from
shading analysis. If the height estimates by Brungart (
1964
) for these three domes
were correct, the domes would have to display shadows of length 13
.
5km,9
.
9km,
and 15
.
7kminFigs.
8.21
c and
8.21
a, respectively, which is clearly not the case.
Similarly, the height estimates for the domes H1-H6 near Hortensius are systemati-
cally higher than those obtained based on photoclinometry and shape from shad-
ing by a factor of two and more, and for the flank slopes values of up to 20
◦
are stated. The height and flank slope values given by Brungart (
1964
) for these
domes would imply large shadows of a length of up to 25 km for the domes in
Fig.
8.22
b, which do not exist. From these results it can be concluded that the height
estimates of Brungart (
1964
) are systematically too high by a significant amount.
This finding clearly shows how difficult it is to accurately measure shadow lengths
in high-contrasted photographic reproductions, since shading effects are easily con-
fused with black shadows, leading to a systematic overestimation of height and flank
slope.
Accurate height measurements of lunar volcanic edifices are presented by Pike
and Clow (
1981
). Their data set primarily contains lunar cones, but they have also
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