Science of Golf and Outgassing

Repub­lished from APRIL 14, 2018

* SPOILER ALERT *

It’s dif­fi­cult to talk about the sci­ence involved in a sto­ry with­out actu­al­ly dis­cussing some of the aspects of the sto­ry. So as a fore­warn­ing, I rec­om­mend that you read the sto­ry first and come back to this arti­cle. I’ll con­tin­ue with the arti­cle in the next para­graph. The sto­ry Golf and Out­gassing is avail­able here.

Golf and Out­gassing is a sto­ry regard­ing the return to the moon some­time in the next decade of an alter­nate his­to­ry.   It revolves around the land­ing site Fra Mau­ro, the loca­tion of the 1971 land­ing of Apol­lo 14 i ii. The title itself is sug­ges­tive of the event end­ing the two-day stay of Apol­lo 14 — Alan Shep­ard’s famous lunar golf shots iii. The out­gassing piece is from part of the pre­lim­i­nary sci­ence results for the mission.

Fra Mau­ro high­lands is a region on the east­ern edge of the Ocean of Storms, near the cen­ter of the disk of the full moon. It was select­ed because of the rel­a­tive­ly recent (and deep) impact crater called Cone Crater. Cone Crater seemed to be deep enough that it might have punched through the under­ly­ing sur­face geol­o­gy and blast­ed pieces of the bedrock dur­ing the impact. One of the sci­ence goals of Apol­lo 14 was to trav­el to the rim of Cone Crater and sam­ple the rocks from with­in. The bulk of the sec­ond EVA involved Alan Shep­ard and Edgar Mitchell work­ing their way up the Cone Crater slope iv v

The rest of the sci­ence back­ground for the Golf and Out­gassing sto­ry is the Apol­lo Lunar Sur­face Exper­i­men­tal Pack­age ALSEP vi. One of the ALSEP exper­i­ments detect­ed water vapor. This occurred weeks lat­er after Shep­pard and Mitchel had depart­ed the moon and returned to the earth. An exper­i­ment called the Suprather­mal Ion Detec­tor Exper­i­ment vii (SIDE) detect­ed the water sig­na­ture viii. It’s like­ly that the result was con­sid­ered void because of no equiv­a­lent event at anoth­er Apol­lo land­ing site. Also, the dry moon par­a­digm became stan­dard. It remained in effect until the Clemen­tine mis­sion sug­gest­ed oth­er­wise ix.

The crawler, or pres­sur­ized rover, is based on a vehi­cle that has been con­sid­ered by NASA as part of the can­celed Con­stel­la­tion pro­gram. It had been devel­oped as part of the desert rats exer­cis­es. The crawler’s capa­bil­i­ties enables lunar explo­ration in a shirt sleeve envi­ron­ment, leav­ing EVA’s to han­dle spe­cial cir­cum­stances that could not be han­dled by robot­ics x

The exis­tence of a sky­light cave struc­ture under Cone Crater is made up for pur­pos­es of the sto­ry. There are sky­light caves on the moon, dis­cov­ered by the Selene (a Japan­ese Lunar Mis­sion) xi They are expo­sures of sub-sur­face lava tubes. Like polar craters, a lava tube could act as a cold trap, allow­ing the volatile sub­stances such as water to accu­mu­late inside of the caves. The expla­na­tion that is inferred in “Golf and Out­gassing” is that the water detect­ed by the SIDE was from a cave con­cealed under Cone Crater that released vapor after the Apol­lo 14 mis­sion. If such a cave exist­ed, dis­cus­sion about return to the moon would like­ly include Fra Mauro.

References

Ref i: NASA Apol­lo 14 page. 

Ref ii: Wikipedia Apol­lo 14 page 

Ref iii: PGA News Lunar Golf Shots 

Ref iv: Fra Mau­ro land­ing site

Ref v: Report on Geol­o­gy of Fra Mauro 

Ref vi: Apol­lo 14 Sci­ence Experiments 

Ref vii: Suprather­mal Ion Detec­tor Experiment