# MARS EXPLORATION ROVER LANDING SITE MEMORANDUM

September 27, 2000

To: Distribution

From: M. Golombek and Tim Parker

Re: Preliminary Definition of Mars Exploration Rover Landing Site
Engineering Requirements and Initial Identification of Potential Landing
Sites

This memo describes the preliminary definition of engineering
requirements on Mars Exploration Rover (MER) landing sites, maps these
requirements into remote sensing criteria, and uses these criteria to
identify potential landing sites. To first order, many of the
engineering requirements are the same as for the Mars Pathfinder mission
\[Golombek et al., 1997\], because the landing system is the same. The
preliminary engineering requirements stated below have been adopted by
the MER Project.

Analysis of the Entry, Descent and Landing (EDL) system and atmospheric
profiles indicates that the MER spacecraft are capable at landing below
--1.3 km MOLA defined elevation, with respect to the MOLA defined geoid
\[Smith and Zuber, 1998; Smith et al, 1999\]. This requirement stems
mostly from the need for an adequate atmospheric density column for the
parachute to bring the spacecraft to the correct terminal velocity.
Because the landing system has no means to reduce horizontal velocity,
low-altitude winds and wind shear together are major concerns and must
be below about 20 m/s.

Preliminary analyses of power generation/usage and thermal cycling of
the rovers restricts the landing sites to be near the subsolar latitude
at arrival to last the required 90 sols. This translates to 15S to 5N
for MER-A and 5S to 15N for MER-B, which arrives at Mars about 52 sols
after MER-A. Operations considerations require the two landing sites to
be separated by a minimum of 37° (solid angle) on the surface.

Surface slopes are an obvious concern for the landing system. Large
slopes can spoof the radar altimeter and/or cause premature or late
firing of the solid rockets and airbag inflation. Small slopes over
large distances can lead to significant additional horizontal velocity
and prolonged bouncing by the lander within the inflated airbags.
Reconstruction of Mars Pathfinder landing indicates the lander traversed
a horizontal distance of about 2 km in 10-20 large bounces across the
surface \[Golombek et al., 1999a\], even though it landed at 3 am local
time when winds should have been calm. Slopes can also affect the
stability of the lander, rover deployment and trafficability, and power
generation. As a result, surface slopes should generally be less than
15°. One relation between measured radar RMS slopes and slope suggests
surfaces with \<6° RMS slopes have about 5% of their surfaces with
slopes \>15° \[e.g., Golombek et al, 1997\]. Images must appear hazard
free (i.e., relatively smooth and flat without obvious hazards, such as
fresh craters).

The airbags of the Mars Pathfinder landing system were qualified to
protect the lander from damage when landing on 0.5 m high rocks in any
orientation \[Golombek et al., 1997\]. As for Pathfinder, this required
a landing site with less than 1% of the surface covered by rocks greater
than 0.5 m high. Model rock size-frequency distributions based on
Viking, Mars Pathfinder and rocky locations on the Earth \[Golombek and
Rapp, 1997; Golombek et al., 1999b\], generally suggest this requirement
can be satisfied at locations with total rock coverage of \<20% as
derived from thermal infrared measurements \[Christensen, 1986b\].

The surface must be radar reflective for the descent radar altimeter to
work properly, so radar reflectivity must be greater than 0.05. The
surface must be load bearing for the rover and too much dust would coat
rocks and could reduce surface lifetime by covering the solar panels.
Extremely high albedo and low thermal inertia regions should therefore
be avoided \[Christensen and Moore, 1992\]. Areas with fine component
thermal inertia of less than 3-4 x 10^-3^ cal cm^-2^ s^-0.5^ K^-1^ or
cgs units (equivalent to 125-165 J m^-2^ s^-0.5^ k^-1^ or SI units)
should therefore be avoided \[Christensen, 1982, 1986a; Mellon et al,
2000\].

We plotted the MOLA elevations within the 30° latitude band from 15N to
15S. Because the southern hemisphere of Mars is dominantly heavily
cratered highlands, little area is actually below --1.3 km in elevation
for MER-A (between 5N and 15S). The largest area below this elevation is
in southern Elysium and Amazonis Planitiae. Unfortunately, most of this
area (150W to 200W) is dominated by extremely low thermal inertia, with
fine component thermal inertias below 3 x 10^-3^ cgs units and so is
excluded. For the latitude band of MER-B (5S to 15N), more area is above
--1.3 km elevation. Nevertheless, most of the area between 135W and 190W
is excluded on thermal inertia grounds. Areas available to seek landing
sites are thus reduced to southern Isidis and Elysium Planitiae in the
eastern hemisphere and western Arabia Terra, Terra Meridiani, Xanthe
Terra, Chryse Planitia, and the bottom of Valles Marineris in the
western hemisphere.

Because of the arrival geometry and the prograde entry into the
atmosphere, landing ellipse size and orientation change significantly
with latitude and time of arrival. Analysis of the expected flight path
angle at atmospheric entry and dispersions produced by the atmosphere
yield landing ellipses of 80 km by 30 km for MER-A at 15S up to 360 km
by 30 km for MER-B at 15N. In addition, the orientation of the ellipse
rotates from 80° at 15S for MER-A to 109° at 15N for MER-B for the
opening of the launch window (for MER-A the ellipse orientations rotate
about 3° counterclockwise by the end of the launch period; for MER-B the
ellipse orientations rotate about 14° counterclockwise by the end of the
launch period). Using the preliminary landing site dispersion data from
P. Knocke and P. Desai, we used the following ellipses for each 2.5° in
latitude for each lander, applicable for the opening of the launch
periods. In reality, the ellipse size probably varies smoothly with
latitude, although the ellipses used are within about 20 km of the
correct length and within a degree of the correct orientation
(sufficient for this preliminary identification). Note all ellipse
widths are 30 km.

## Table 1. Ellipse data for MER-A and MER-B

Latitude Ellipse Length Ellipse Orientation

(deg.) (major axis, km) (orientation of major axis, deg.)

MER-A

15S-12.5S 86 81

12.5S-10S 97 81

10S-7.5S 109 83

7.5S-5S 120 84

5S-2.5S 132 86

2.5S-0 140 87

0-2.5N 155 87

2.5N-5N 166 88

MER -- B

5S-2.5S 132 103

2.5S-0 140 104

0-2.5N 155 104

2.5N-5N 166 105

5N-7.5N 195 106

7.5N-10N 240 107

10N-12.5N 286 107

12.5N-15N 330 109

Next using these landing ellipses, we tried to place them in all
locations that are below --1.3 km in elevation, had acceptable fine
component thermal inertia values, and were free of obvious hazards in
the MDIMs (Mars Digital Image Mosaics). This is exactly the same
procedure employed to initially identify potential landing sites for
Mars Pathfinder. Only sites that appear smooth and flat in the MDIM
without scarps, large hills, depressions or large fresh craters (\>5 km)
were acceptable.

To our surprise, we found 100 sites for MER-A and 85 sites for MER-B
that met these criteria (30 sites overlap). Even though the area
available to land north of the equator is at least twice as great as
south of the equator, the smaller ellipse size towards the south
compensates. For comparison, the landing ellipse for Mars Pathfinder
(300 km by 100 km) and the 10° latitude band reduced available sites to
just 10 \[Golombek et al., 1997\]. Virtually all ages and types of
geologic mapped units are available for landing including ancient
Noachian units, Hesperian channel and plains, and Amazonian volcanics,
channel and smooth plains. The Hematite site studied for the Mars
Surveyor '01 lander is assessable to both landers, with 4-5 sites for
each (TM20B-TM23B; TM9A-TM12A) and 19 sites (VM35A-VM53A) can be placed
within Valles Marineris (guaranteed spectacular views). We have not yet
evaluated any of these potential sites in more detail, so it is unclear
how many would survive the more careful review required to certify a
landing site. If the Pathfinder site selection activity is used as a
guide, at least half would be eliminated fairly quickly on the basis of
inspection of existing MOC images. Nevertheless, this analysis shows a
large number of landing sites are available for study for the MER
landers. The 30 sites that overlap in area are: TM1A-TM11B, TM2A-TM11B,
TM4A-TM12B, TM5A-TM13B, T6A-TM14B, TM7A-TM17B, TM8A-TM16B, TM9A-TM19B,
TM10A-TM20B, TM11A-TM22B, TM12A-TM23B, TM13A-TM24B, TM14A-TM25B,
XT18A-XT28B, XT20A-XT29B, XT21A-XT30B, XT33A-XT31B, XT34A-XT27B, EP
68A-EP52B, EP70A-EP56B, EP72A-EP57B, EP74A-EP61B, EP75A-EP63B,
EP76A-EP64B, EP78A-EP71B, EP80A-EP70B, EP81A-EP72B, EP83A-EP79B,
IP84A-IP96B, IP85A-IP98B.

Below is a list of all potential sites identified. This list is not
meant to be exclusive or inclusive; it is merely to identify the scope
of choices available. Each site is given a unique identifier consisting
of 2 letters, followed by a number, followed by the letter A or B, for
purposes of communication. The first two letters define the general
region in which the landing site is located as follows: wA-western
Arabia Terra, TM-Terra Meridiani, CP-Chryse Planitia, XT-Xanthe Terra,
and VM-Valles Marineris (all in the western hemisphere), and EP-Elysium
Planitia, IS-Isidis Planitia, and SM-Syrtis Major (all in the eastern
hemisphere). The number is the unique site number for MER-A or MER-B,
which is distinguished by the letter A for MER-A and B for MER-B. The
location is for the center of the ellipse; corresponding ellipse sizes
can be found in Table 1. The elevation is approximate for the center of
the ellipse and is within 0.5 km for elevations --6 km to --2.5 km and
within 0.1 km for elevations --2.5 km to --1.3 km. Geologic units from
Scott and Tanaka \[1986\] and Greeley and Guest \[1987\] are: Npl~1~ --
Noachian Plateau cratered unit; Npl~2~ -- Noachian Plateau subdued
cratered unit; Npl~h~ -- Noachian Plateau hilly unit; Npl~d~ -- Noachian
Plateau dissected unit; Hr -- Hesperian Ridged plains; Hch -- Hesperian
Channel Material; Hvr -- Hesperian Vastitas Borealis Formation, ridged;
Hs -- Hesperian Syrtis Major Formation (volcanics); Ael~1~ -- Amazonian
Elysium volcanics, Achu -- Amazonian Channel material; Aml -- Amazonian
Medusae Fossae Formation; Aps -- Amazonian Smooth Plains; Apk --
Amazonian knobby material; Avf -- Amazonian Valles Marineris floor
material; S -- Smooth plains material within craters

## Table 2. Potential landing sites for MER-B and MER-A

MER-B. Western Hemisphere

+-------------+--------------+-------------+--------+----------------+
| Site ID     | Location of  |             | Ele    | Geological     |
|             | Ellipse      |             | vation | Unit           |
|             | Center       |             | (km),  |                |
|             |              |             |        |                |
|             | (Ellipse     |             |        |                |
|             | size can be  |             |        |                |
|             | found in     |             |        |                |
|             | tables       |             |        |                |
|             | above)       |             |        |                |
+-------------+--------------+-------------+--------+----------------+
| A=MER-A     | Latitude(°N, | Longitude   | Re     | Scott & Tanaka |
|             | °S)          | (°W)        | lative | \[1986\];      |
| B=MER-B     |              |             | to     | Greeley &      |
|             | Latitude     | Long.±0.2°  | MOLA   | Guest \[1987\] |
|             | ±0.2°        |             | geoid  |                |
+-------------+--------------+-------------+--------+----------------+
| wA1B        | 14.4N        | 7           | -1.9   | Npl~1~         |
+-------------+--------------+-------------+--------+----------------+
| wA2B        | 13N          | 10.7        | -1.7   | Npl~1~         |
+-------------+--------------+-------------+--------+----------------+
| wA3B        | 9.2N         | 6           | -2.1   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| wA4B        | 7.8N         | 10.8        | -2.0   | Npl~1~         |
+-------------+--------------+-------------+--------+----------------+
| wA5B        | 11.2N        | 17.6        | -1.9   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| wA6B        | 8.6N         | 18.6        | -2.1   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| wA7B        | 6.5N         | 15.2        | -1.9   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| wA8B        | 10.7N        | 23.7        | -2.5   | Npl~1~         |
+-------------+--------------+-------------+--------+----------------+
| TM9B        | 6N           | 2.7         | -1.3   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM10B       | 5.6N         | 8.3         | -1.7   | Npl~1~         |
+-------------+--------------+-------------+--------+----------------+
| TM11B       | 4.2N         | 7.8         | -1.8   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM12B       | 4N           | 13.5        | -2.1   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM13B       | 2.3N         | 12          | -1.9   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM14B       | 0.9N         | 6.7         | -1.6   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM15B       | 0.3N         | 9.7         | -1.9   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM16B       | 0.6S         | 11.2        | -1.9   | Npl~1~         |
+-------------+--------------+-------------+--------+----------------+
| TM17B       | 0.5S         | 9           | -2.1   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM18B       | 1.2S         | 9.5         | -1.7   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM19B       | 1.2S         | 5.3         | -1.3   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM20B       | 2.3S         | 6.2         | -1.3   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM21B       | 2.5S         | 3.3         | -1.3   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM22B       | 3.2S         | 7.1         | -1.7   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM23B       | 3.4S         | 3.1         | -1.4   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| TM24B       | 2.8S         | 10.1        | -1.8   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM25B       | 3.6S         | 10.1        | -1.7   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| TM26B       | 4.6S         | 10.1        | -1.7   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| XT27B       | 1.9S         | 22.5        | -2.1   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT28B       | 1.2S         | 24.5        | -1.8   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT29B       | 1.0S         | 27.7        | -1.7   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT30B       | 1.2S         | 30.6        | -2.0   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT31B       | 4N           | 26.2        | -1.8   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT32B       | 4.5N         | 34.6        | -1.9   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT33B       | 3.2N         | 38.4        | -1.6   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| XT34B       | 6.2N         | 40.6        | -1.6   | Npl~2~         |
+-------------+--------------+-------------+--------+----------------+
| CP35B       | 0.4S         | 33.8        | -5.5   | Hch            |
+-------------+--------------+-------------+--------+----------------+
| CP36B       | 8.2N         | 33.0        | -4.0   | Hch            |
+-------------+--------------+-------------+--------+----------------+
| CP37B       | 10.5N        | 45.6        | -2.5   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| CP38B       | 11.8N        | 45.4        | -2.5   | Hr             |
+-------------+--------------+-------------+--------+----------------+
| CP39B       | 14.1N        | 47.0        | -3.0   | Hr             |
+-------------+--------------+-------------+--------+----------------+

MER-B. Eastern Hemisphere

  -------------- --------------- -------------- ----------- ----------------
                 Location                                   

  Site ID        Latitude(°N,    Longitude (°W) Elevation   Geological Unit
                 °S)                                        

  EP40B          14.2N           201.3          -2.1        Ael~1~

  EP41B          14.3N           204.0          -1.9        Ael~1~

  EP42B          13.4N           203.1          -1.9        Ael~1~

  EP43B          12.4N           203.0          -2.1        Ael~1~

  EP44B          11.5N           204.1          -2.5        Ael~1~

  EP45B          7.2N            201.0          -3.0        Achu

  EP46B          12.6N           208.7          -1.9        Ael~1~

  EP47B          11.2N           207.4          -2.5        Ael~1~

  EP48B          9.2N            206.8          -2.5        Ael~1~

  EP49B          7.4N            205.6          -3.0        Ael~1~

  EP50B          6.6N            207.6          -3.0        Ael~1~

  EP52B          5.3N            208.0          -3.0        Achu

  EP53B          11.0N           211.8          -2.1        Ael~1~

  EP54B          8.2N            211.7          -2.5        Ael~1~

  EP55B          5.6N            213.7          -2.5        Achu

  EP56B          4.4N            213.6          -2.5        Achu

  EP57B          4.2S            212.1          -1.7        Aml

  EP58B          10.7N           219.5          -2.5        Aps

  EP59B          7.2N            217.0          -3.0        Ael~1~

  EP60B          6.5N            219.6          -3.0        Aps

  EP61B          3.7N            216.0          -3.0        Achu

  EP62B          3.6N            218.5          -3.0        Aml

  EP63B          0.7S            216.9          -2.5        Aps

  EP64B          1.5S            217.8          -3.0        Aps

  EP65B          14N             223.8          -2.5        Aps

  EP66B          115N            224.1          -3.0        Aps

  EP67B          9.2N            221.2          -3.0        Aps

  EP68B          5.6N            222.9          -3.0        Aps

  EP69B          3.6N            223.4          -3.0        Aps

  EP70B          3.1N            225.0          -3.0        Aps

  EP71B          1.6N            220.6          -3.0        Aps

  EP72B          0.4S            224.9          -3.0        Aps

  EP73B          12.9N           225.6          -2.5        Aps

  EP74B          8.8N            225.9          -2.5        Aps

  EP75B          6.8N            227.6          -2.5        Aps

  EP76B          14.1N           230.1          -3.0        Hr

  EP77B          13.0N           232.5          -3.0        Hr

  EP78B          11.2N           236.1          -2.5        Hr

  EP79B          3.7N            235.5          -1.6        Apk

  EP80B          13.9N           244.1          -2.5        Hr

  EP81B          12.1N           245.2          -2.5        Hr

  IP82B          14.1N           236.6          -3.5        Hr

  IP83B          13.5N           265.1          -3.5        Aps

  IP84B          12.8N           265.8          -3.5        Aps

  IP85B          11.6N           265.5          -3.5        Aps

  IP86B          11.0N           268.7          -3.5        Aps

  IP87B          9.7N            266.4          -3.5        Aps

  IP88B          8.3N            268.1          -3.5        Aps

  IP89B          13.7N           271.2          -4.5        Aps

  IP90B          14.0N           274.6          -4.5        Hvr

  IP91B          11.2N           275.5          -4.5        Hvr

  IP92B          8.9N            272.1          -4.5        Hvr

  IP93B          8.2N            274.6          -4.5        Hvr

  IP94B          6.9N            271.0          -4.5        Hvr

  IP95B          5.6N            272.0          -4.5        Hvr

  IP96B          4.6N            272.3          -4.5        Aps

  IP97B          5.7N            276.6          -4.5        Aps

  IP98B          4.7N            276.4          -4.0        Aps

  SM99B          8.1N            279.7          -4.0        Hs

  SM100B         7.1N            280.3          -2.5        Hs
  -------------- --------------- -------------- ----------- ----------------

MER-A. Western Hemisphere

  -------------- --------------- -------------- ----------- ----------------
                 Location                                   

  Site ID        Latitude(°N,    Longitude (°W) Elevation   Geological Unit
                 °S)                                        

  TM1A           4.6N            7.8            -1.8        Npl~2~

  TM2A           4.0N            7.1            -1.7        Npl~2~

  TM3A           3.7N            10.1           -1.7        Npl~1~

  TM4A           4.2N            13.1           -1.9        Hr

  TM5A           2.0N            11.0           -1.8        Npl~1~

  TM6A           0.9N            6.6            -1.6        Npl~2~

  TM7A           0.2S            8.9            -1.9        Hr

  TM8A           0.2S            10.4           -1.9        Hr

  TM9A           1.2S            5.6            -1.3        Npl~2~

  TM10A          2.2S            6.6            -1.7        Npl~2~

  TM11A          3.4S            6.9            -1.6        Npl~2~

  TM12A          3.6S            2.9            -1.3        Npl~2~

  TM13A          2.9S            10.5           -1.8        Hr

  TM14A          3.8S            10.1           -1.8        Hr

  TM15A          8.6S            6.7            -1.9        S

  TM16A          9.4S            6.6            -1.9        S

  TM17A          11.0S           7.2            -1.4        Npl~d~

  XT18A          0.4S            24.5           -1.8        Npl~2~

  XT19A          1.1S            25.2           -1.7        Npl~2~

  XT20A          1.0S            27.7           -1.8        Npl~2~

  XT21A          1.5S            30.7           -1.7        Npl~2~

  XT22A          4.7S            16.7           -1.9        Npl~1~

  XT23A          5.4S            17.7           -1.8        Npl~1~

  XT24A          5.3S            12.8           -1.9        Npl~1~

  XT25A          5.7S            12.4           -1.8        Npl~1~

  XT26A          7.7S            15.5           -1.8        Npl~h~

  XT27A          7.7S            13.6           -1.5        Npl~1~

  XT28A          7.2S            11.4           -1.6        Npl~1~

  XT29A          9.3S            15.5           -1.5        Npl~1~

  XT30A          8.8S            11.7           -1.4        Npl~1~

  XT31A          10.8S           15.8           -1.4        Npl~1~

  XT32A          10.7S           10.7           -1.4        Npl~2~

  XT33A          4.2N            26.3           -1.4        Npl~2~

  XT34A          1.9S            22.7           -1.9        Npl~2~
  -------------- --------------- -------------- ----------- ----------------

MER-A. Western Hemisphere, Valles Marineris

  -------------- --------------- -------------- ----------- ----------------
                 Location                                   

  Site ID        Latitude(°N,    Longitude (°W) Elevation   Geological unit
                 °S)                                        

  VM35A          9.4S            34.5           -5.0        Hch

  VM36A          10.2S           36.6           -4.5        Hch

  VM37A          11.1S           37.9           -4.0        Hch

  VM38A          8.2S            40.5           -3.5        Hch

  VM39A          12.8S           40.0           -3.5        Hch

  VM40A          8.8S            42.9           -3.5        Hch

  VM41A          14.0S           42.0           -4.0        Hch

  VM42A          7.7S            50.7           -4.5        Avf

  VM43A          13.9S           57.5           -5.5        Avf

  VM44A          13.1S           62.5           -4.5        Avf

  VM45A          12.0S           67.7           -4.5        Avf

  VM46A          13.6S           70.6           -3.5        Avf

  VM47A          6.2S            70.1           -5.0        Avf

  VM48A          7.1S            72.5           -5.0        Avf

  VM49A          9.2S            73.5           -4.0        Avf

  VM50A          9.7S            73.8           -3.5        Avf

  VM51A          10.1S           73.0           -3.5        Avf

  VM52A          10.5S           72.5           -3.5        Avf

  VM53A          8.8S            77.7           -3.5        Avf
  -------------- --------------- -------------- ----------- ----------------

MER-A Eastern Hemisphere

  -------------- --------------- -------------- ----------- ----------------
                 Location                                   

  Site ID        Latitude(°N,    Longitude (°W) Elevation   Geological Unit
                 °S)                                        

  EP54A          11.4S           181.9          -1.5        Aml

  EP55A          14.2S           184.8          -1.9        Hch

  EP56A          14.6S           188.1          -1.6        Npl~1~

  EP57A          9.0S            191.4          -3.0        Apk

  EP58A          9.9S            191.5          -3.0        Apk

  EP59A          10.4S           191.6          -2.5        Apk

  EP60A          13.1S           194.1          -1.6        Npl~1~

  EP61A          11.8S           195.5          -1.9        Apk

  EP62A          9.7S            198.2          -1.8        Apk

  EP63A          12.6S           196.5          -1.6        Npl~1~

  EP64A          14.8S           197.5          -2.1        Npl~1~

  EP65A          8.7S            202.6          -1.7        Apk

  EP66A          4.0N            206.5          -3.5        Achu

  EP67A          4.6N            209.6          -3.5        Achu

  EP68A          3.5N            209.2          -3.5        Achu

  EP69A          9.3S            209.5          -1.7        Npl~1~

  EP70A          4.0N            213.5          -3.5        Achu

  EP71A          1.2N            212.0          -3.5        Achu

  EP72A          4.2S            211.4          -1.7        Aml

  EP73A          5.5S            212.0          -1.7        Aml

  EP74A          4.2N            216.6          -3.5        Achu

  EP75A          0.7S            217.2          -3.5        Aps

  EP76A          1.4S            217.5          -2.5        Aps

  EP77A          4.5N            220.5          -3.5        Aps

  EP78A          1.7N            221.0          -3.5        Aps

  EP79A          4.5N            224.4          -3.5        Aps

  EP80A          3.2N            224.3          -3.5        Aps

  EP81A          0.2S            224.7          -3.5        Aps

  EP82A          5.8S            222.4          -4.5        S

  EP83A          3.5N            234.7          -1.7        Apk

  IP84A          4.5N            271.9          -4.5        Aps

  IP85A          4.5N            271.9          -4.5        Aps
  -------------- --------------- -------------- ----------- ----------------

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