Since part of Japan appears on the map, there are theories that Chinese and Arab expeditions had reached the Pacific Ocean …. This map precedes the Portuguese nautical charts that show the tip of Africa. The west coast of Africa, on the other hand, is not as well defined as the east coast, with a river mouth at the level of the Gulf of Guinea. The map was completed on April 24, and sent to Portugal, but has since been lost. The hilly region was designated the Fra Mauro formation, a widespread geological area covering large portions of the lunar surface around Mare Imbrium Sea of Rains.
The mile km wide Mare Imbrium is the largest recognizable impact structure on the Moon, and is thought to have been formed by a major impact of a huge mass colliding with the Moon during the period when the Earth and the planets were forming. The Fra Mauro formation is believed to be made up of an ejecta blanket thrown out by that impact.
The area is characterized by ridges a few hundred feet high which radiate from the Imbrium basin separated by undulating valleys. The ejecta blanket now is buried by younger rubble and lunar soil churned up by more recent meteoroid impacts and possible moonquakes. Also, selected landing sites had to accomplish high-priority science objectives within the confines of two 4-hour-long walking EVAs. Apollo 13 was targeted to land in the geologic unit known as the Fra Mauro Formation, which was formed as ejecta from the impact that formed the Imbrium Basin.
Fra Mauro material had already been mapped through Earth-based telescopes as being widely distributed across the nearside of the Moon. It therefore serves as a convenient stratigraphic marker, dividing features that are older than the Imbrium impact from those that are younger.
By returning samples of the Fra Mauro Formation for study on Earth, a precise age could be assigned to this geologic transition.
Also, because the Fra Mauro was ejected by the Imbrium impactor, it was hoped that it would provide samples that originated deep in the Moon's crust, perhaps from tens of kilometers below the surface. The specific landing site within the Fra Mauro Formation was chosen to be near Cone Crater, a young, fresh, meter-diameter impact structure. Cone Crater was chosen because it is large enough to penetrate through the lunar regolith that has been deposited since the Fra Mauro Formation was formed.
In a sense, Cone Crater served as a natural drill core, exposing the rocks that were the main objective of the landing. Prior to the abort of Apollo 13, Apollo 14 was targeted to land in the Littrow region of Mare Serenitatis, where the objective was to study young, pyroclastic volcanic deposits.
Following the Apollo 13 abort, it was decided to retarget Apollo 14 to the Fra Mauro site, which was regarded as scientifically more important than the Littrow site. Also, landing in Fra Mauro would allow the astronauts to obtain orbital photography of the Descartes region, something that was not possible if Littrow was the landing site. Descartes was regarded as a high-priority target for a later mission eventually flown by Apollo 16 , but could not be certified as a safe landing site based on Lunar Orbiter photography.
Although Littrow was rejected as the Apollo 14 landing site, another site in Mare Serenitatis, Taurus-Littrow, was later explored by Apollo Apollo 14 site: Enlargement of high-resolution view Cone Crater the sharp-rimmed crater at the upper right portion of the photograph was visited by astronauts Alan Shepard and Ed Mitchell during the second EVA.
The astronauts got to within 20 meters of the rim crest of Cone Crater. These glasses have a red lens over the left eye and green or blue lens over the right eye. Black and White Images To view side-by-side stereo pairs, use pocket stereo viewers obtainable from local educational suppliers, bookstores, etc. Side-by-side stereo pairs can also be viewed with the unaided eye by focusing on each image separately and allowing the eyes to cross.
If you wear glasses, it may be necessary to remove them and view the pairs from 6 to 10 inches away. These techniques may require some practice the Apollo 15, 16 and 17 stereo pairs are good for this purpose.
Another means of assisting this process is to place an index card upright between the two images, forcing each eye to see the different images. This was the first landing in terrain with significant relief.
These views Hasselblad frames AS and AS show an area 24 kilometers across from top to bottom, with north to the top.
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