A detail from this geology map suggests why the grouping of craters at the landing site is called "The Snowman". West is at the top, so this is roughly the orientation Pete would have seen during the approach. The white circles drawn around the craters indicate the likely extent of the ejecta blankets. It is, I believe, the combination of white circles in the target area that made someone think of a Snowman: Surveyor Crater forming the torso at the center, two smaller craters at the bottom forming the feet, and a medium-sized crater at the top forming the head. The latter crater, of course, was given the name Head Crater. I have been unable to confirm this supposition, nor does anyone remember who gave "The Snowman" his name; but it would have been very much in character for Pete Conrad to have done so.Western Map without geology markings (2 Mb )
Four possible traverses were laid out in the area covered by LSE 7-6 and the next map section north, LSE 7-7. If Pete was able to land close to Surveyor Crater, it was expected that one of these traverses could be lightly modified for use. The actual traverse was a modification of the Site 4 traverse, as handrawn on the map below.
I don't know who sketched an approximation of the actual Apollo 12 traverse on this map, but two features of the sketch itself suggest that it represents a propsed traverse devised during the rest period between the EVAs and then copied on this 'PAO' map set.
First, the LM is plotted on the map at Q.5/14.2, which is the location that Pete gives to Houston at about 121:19:56, once he is back in the cabin after the first EVA-1 and has had a chance to think about where he landed. Post-mission analysis put the LM 50 meters farther west at about Q.5/1.52, a trivial difference.
Second, the sketch shows Pete and Al leaving Halo Crater and going directly north into Surveyor Crater, but staying on the west inner wall, well away from Surveyor III to avoid any chance of it sliding down on them, and then looping back to approach the spacecraft from the north. When Pete first got on the surface at the start of EVA-1 at 115:23:55, he told Houston that Surveyor III seemed to be sitting on a much steeper slope than the 14 degrees they had been expecting. He later speculated that he was being fooled by an optical illusion, which turned out to be true. The deep shadow on the eastern wall was making the slope look far steeper than it really was. After EVA-1, Pete suggested at 121:16:33 that it might be best to approach the Surveyor from the west and the sketch on this map seems to be Houston's elaboration of that idea. At 133:36:55, Gibson alludes to this thinking when he suggests to Pete and Al that they shouldn't approach the Survayor from directly below.
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