**STS-55 Debrief**

**May 24, 1993**

**La Paz, capital city of Bolivia S55-81D-016**

This NW-looking view shows Lake Titicaca on the high Andean plateau and
La Paz, Bolivia\'s capital city. LA Paz (4 million) lies partly on the
plateau and partly down in the enormous canyons which have cut the
flanks of the plateau.

**Glacial Lakes, Andes Mts., Bolivia S55-85D-039**

This SW-looking view shows a series of charactreristicallyelongated
lakes which are formed by the action of flowing ice. In the recent
geological past, the wet eastern margins of the Andes Mts in Bolivia
were cold enough to allow glaciers to substantially lower levels than
today. These are some of the best pictures of the ice- scoured lakes on
the plateau rim of the Bolivian Andes.

**R'o Grande Dust Plumes, Bolivia S55-81D-040**

The eastern flanks of the Andes in Bolivia are often subjected to strong
northerly winds. This wind is strong enough to generate long plumes of
dust from the exposed sand bars in the river, especially from those
reaches of the river that are aligned with the wind. The river meanders
in a regular way which in turn leads to a regular set of dust plumes.
This is an unexpected geologic phenomenon since blowing dust is thought
to be a feature of dry lands rather than forested country as this is.
The first views of the phenomenon were thought to represnt freak events.
However, STS-55 is the fourth mission in eight years to acquire such
views. This indicates without doubt that the phenomenon is a common
feature. Such dust events may explain the surprising fact that the
forest to the south in Argentina is rooted in soils made of blown dust.

**Amazon River (?), Brazil S55-86-44**

The CIR film has yielded a striking example of the pattern of large
levees along the Amazon river, or one of its major tributaries. Levees
are often difficult to identify in rainforests because of vegetation and
other obscuring factors. The river is in partial flood as can be seen
from the fact that the river water is not confined within the levees in
most places.

**Beaded Drainage Pattern, N. Brazil S55-86-115, -116**

The rivers in this remote are almost never photographed (on the
watershed between the upper reaches of the R'o Branco and the Essequibo
River in Guyana). This strange river pattern, like beads threaded on a
string, is suggestive of limestone country where solutional attack of
rocks is widespread.

**Himalaya Mountains, Nepal, Tibet S55-81D-083**

This is one of the clearest and most three-dimensional views of the
Himalayas. Low sun angles, an oblique look-angle and clean air help to
make this one of the best photographs of the great Himalaya Range,
although there are numerous fine competitors in the collection of
handheld photographs.

**Sudd Swamp, Sudan S55-73-009**

The Sudd is one of the largest swamplands in Africa. Often
cloud-covered, this is a fine view of a part of the Sudd, a vast wetland
where the Blue Nile breaks out of the east African highlands. The
wetland ecology of the swamps is being threatened by the Jonglei Canal
which syphons off life-giving water at the upstream end and leads it to
the downstream end to enlarge the supply of water in the Blue Nile,
water which would otherwise be consumed by swamp vegetation and
evaporation.

**Okavango Swamps, Botswana, Southern Africa S55-84-38, and -40**

This dramatic south-looking view shows the fault lines which define the
downstream side of the great inland delta of the Okavango River, a river
which rises in the wet highlands of southern Angola and flows into the
arid Kalahari desert where it declines and dies in the Okavango Swamp.
The town of Maun can be discerned on the Thamalakane River. Details of
stream pattern and activity are available from this photograph. The
Okavango Swamps are threatened by deforestation and draining of water
for distant mines in the desert. But the Swamps have become a tourist
destination for people from many parts of the world. This may help stem
the tide of destruction of the swamp forests.

**Saharan Dust, West Africa S55-151-004**

One of the longest-duration dust outblow events occurred during the
flights of STS-55 and -56. Dust has been blowing from the Sahara towards
the Americas for several weeks as of this writing. Here dust can be seen
over Conakry in West Africa, in one small part of the vast pall which
reached South America in the first days of its existence.

**Saharan Dust, Fogo, Cape Verde Islands S55-86D-79**

One of the longest-duration dust outblow events occurred during the
flights of STS-55 and -56. Here the tip of the volcanic Cape Verdean
island of Fogo (9,300\' above sea level) can be seen sticking out above
a thick layer of dust which completely obscures the sea surface.

*Justin Wilkinson¾Geomorphology*

**STS055-81D-016 La Paz, Capital City of Bolivia**

This northwest-looking view shows Lake Titicaca on the high Andean
plateau and La Paz, BoliviaÕs capital city. La Paz (pop. 4 million) lies
partly on the plateau and partly down in the enormous canyons which have
cut the flanks of the plateau.

**STS055-85D-039 Glacial Lakes, Andes Mountains, Bolivia**

This southwest-looking view shows a series of characteristically
elongated lakes which were formed by the action of flowing ice. In the
recent geological past, the wet eastern margins of the Andes Mountains
in Bolivia were cold enough to allow glaciers to exist at substantially
lower levels than today. These are some of the best pictures of the
ice-scoured lakes on the plateau rim of the Bolivian Andes.

**STS055-81D-040 R'o Grande Dust Plumes, Bolivia**

The eastern flanks of the Andes in Bolivia are often subjected to strong
northerly winds. These winds are strong enough to generate long plumes
of dust from the exposed sandbars in the river, especially from those
reaches of the river that are aligned with the wind. The fact that the
river meanders in a regular way leads to the creation of a regular set
of dust plumes. This is an unexpected geologic phenomenon, since blowing
dust is thought to be a feature of dry lands rather than forested
country, as this is. The first views of the phenomenon were thought to
represent freak events. However, STS-55 is the fourth mission in 8 years
to acquire such views. This indicates without doubt that the phenomenon
is common. Such dust events may explain the surprising fact that the
forest to the south in Argentina is rooted in soils made of blown dust.

**STS055-86-044 Amazon River (?), Brazil**

The CIR film has yielded a striking example of the pattern of large
levees along the Amazon River (or one of its major tributaries). Levees
are often difficult to identify in rain forests because of vegetation
and other obscuring factors. The river is in partial flood, as can be
seen from the fact that the river water is not confined within the
levees in most places.

**STS055-86-115 and -116 Beaded Drainage Pattern, Northern Brazil**

The rivers in this remote area (on the watershed between the upper
reaches of the R'o Branco in Brazil and the Essequibo River in Guyana)
are almost never photographed. This strange river pattern, like beads
threaded on a string, is suggestive of limestone country, where
solutional attack of rocks is widespread.

**STS055-81D-083 Himalaya Mountains, Nepal and Tibet**

This is one of the clearest and most three-dimensional views of the
Himalayas. Low Sun angles, an oblique look-angle, and clean air help to
make this one of the best photographs of the great Himalayan Range,
although there are numerous fine competitors in the collection of
hand-held photographs.

**STS055-73-009 Sudd Swamp, Sudan**

The Sudd is one of the largest swamplands in Africa. This is a fine view
of the often cloud-covered Sudd Swamp, a vast wetland where the Blue
Nile breaks out of the east African highlands. The wetland ecology of
the swamp is being threatened by the Jonglei Canal, which syphons off
life-giving water at the upstream end and leads it to the downstream end
to enlarge the supply of water in the Blue Nile, water which would
otherwise be consumed by swamp vegetation and evaporation.

**STS055-84-038 and -040 Okavango Swamp, Botswana, Southern Africa**

This dramatic south-looking view shows the fault lines that define the
downstream side of the great inland delta of the Okavango River, a river
which rises in the wet highlands of southern Angola and flows into the
arid Kalahari Desert, where it declines and dies in the Okavango Swamp.
The town of Maun can be discerned on the Thamalakane River. Details of
stream pattern and activity are available in this photograph. The
Okavango Swamp is threatened by deforestation and draining of water for
distant mines in the desert. But the Swamp has become a tourist
destination for people from many parts of the world. This may help stem
the tide of destruction of the swamp forests.

**STS055-151-004 Saharan Dust, West Africa**

One of the longest-duration dust outblow events occurred during the
flights of STS-55 and -56. As of this writing, dust has been blowing
from the Sahara towards the Americas for several weeks. Here dust can be
seen over Conakry in west Africa, in one small part of the vast pall,
which reached South America in the first days of its existence.

**STS055-86D-079 Saharan Dust, Fogo, Cape Verde Islands**

One of the longest-duration dust outblow events occurred during the
flights of STS-55 and -56. Here the tip of the volcanic Cape Verde
island of Fogo (9300 feet above sea level) can be seen sticking out
above a thick layer of dust, which completely obscures the sea surface.

*Fred Brumbaugh¾Environment*

**STS055-152-062 or -065;**

**STS055-95-092 (synoptic);**

**and STS046-75-030 & -031**

**Lake Eyasi, Tanzania**

This comparison of STS-46 photographs (taken August 4, 1992) and STS-55
photographs (taken May 3, 1993) of Lake Eyasi is an excellent example of
how rapidly water levels can change in this shallow East African Rift
Valley lake. The primary source of water for this lake is the Sibiti
River, which enters Lake Eyasi from the southwest.

**STS055-152A-217 or -218 East Coastal Area of Kalimantan, Indonesia**

Substantial development can be seen along this coastline of the province
of Kalimantan in Indonesia. These development activities include oil and
gas exploration, mining, and the construction of a new port and
transshipment facilities along the coast. New ÒscarsÓ from either
pipeline or highway construction are evident.

**STS055-152A-208 and -210**

**Coastal Area of East Malasia (Sarawak)**

Similar to the scenes from northwestern Madagascar, specifically the
Betsiboka Estuary, this view of the Sarawak coast shows large quantities
of sediment being transported into the South China Sea. This is
primarily the result of extensive logging and subsequent erosion of one
of the oldest rain forests on Earth.