Practice Challenge 2 - National Cipher Challenge 2019

Tjf, B sppx r ippx rs sqj ubij vpd hjes pojw rey bs zrh mdhs r wpsrsbpe nbaqjw raaibjy sp sqj sjks. Rs ubwhs bs zrh qrwy sp hrv bu sqrs zrh r cdf pw r ujrsdwj rey epwtriiv B zpdiy rhhdtj cdf, cds bs hjjtjy pyy sqrs bs zrh sqj peiv ubij sqrs zrh ruujnsjy hp B rhxjy rwpdey sp hjj bu revpej qry hjje revsqbef hbtbirw. Bs sdweh pds sqrs sqbh zrh eps sqj ubwhs erobfrsbpe awpcijt sp qbs sqj awpfwrttj. Fjej wjapwsjy r trmpw bhhdj zbsq sqj fdbyrenj awpfwrttj upw Heppav pe sqj Rapiip Sje tbhhbpe zqbnq npdiy rfrbe qroj nrdhjy r trmpw awpcijt. Upw hptj wjrhpe sqj awpfwrttj npeswpiibef sqj ireybef wryrw zrhe’s dayrsjy zbsq sqj uibfqs aire rey bu Fjej qrye’s wrbhjy sqrs zbsq Bojwhpe sqje sqj cpvh tbfqs qroj qry wjri swpdcij fjssbef crnx. B ippxjy sqwpdfq sqj nptarev ubijh rey updey repsqjw pu pdw tvhsjwbpdhiv upwtrssjy wjapwsh: sqj tjtp beupwtbef sqjt rcpds sqj nqrefj, zqbnq jkairbeh zqv sqj awpfwrttj ejojw fps dayrsjy. Sqbh sbtj sqj nbaqjw zrh re ruubej hqbus, hp hibfqsiv qrwyjw sp nwrnx, cds epsqbef hjwbpdh. Hsbii, bs bh tdnq ijhh ibxjiv sqrs bs zrh r cdf sqrs sbtj, rey be rev nrhj szbnj bh spp tdnq pu r npbenbyjenj. Bs yby hsrws tj zpeyjwbef zqv sqj hjnpey nbaqjw zrh jrhbjw sp nwrnx sqre sqj ubwhs, cds sqje B wjribhjy sqrs sqj ruubej hqbus zrh spp tdnq pu r fbojrzrv. R wpsrsbpe nbaqjw wjriiv npdiy mdhs cj re jenpybef jwwpw, cds sqj ruubej hqbus bh spp hpaqbhsbnrsjy upw r tbhsrxj, hp zqpjojw trefijy sqj wjapwsh tdhs qroj wjribhjy sqjv qry tryj r cbs pu re jwwpw zbsq sqj ubwhs pej rey swbjy sp npojw sqjbw hsjah zbsq sqj hjnpey. Bs bh qrwy sp hjj sqbh rh revsqbef psqjw sqre rssjtasjy hrcpsrfj, cds B rt eps hdwj zqrs sqj tpsboj npdiy cj. B ypdcs bs bh ajwhperi. Sqj Rapiip Sje rey Jijoje nwjzh ype’s pojwira, hp jbsqjw hptjpej qrh r fwdyfj rfrbehs sqj zqpij Rhswperds npwah pw sqjv rwj swvbef sp yjwrbi sqj Rapiip awpfwrttj. Bs npdiy cj sqj Hpobjsh B hdaaphj. Rs ubwhs, B sqpdfqs sqrs sqjbw zbiibefejhh sp hqbus sqj IDER-UBUSJJE pwcbs hqpzjy sqrs sqjv zjwje’s arws pu bs, cds hptjpej be sqj Hsrsj Yjarwstjes apbesjy pds sqrs sqjv tbfqs mdhs qroj qry r fdbisv npehnbjenj, pw cjje xjje sp ybhsrenj sqjthjiojh penj sqj aips zrh ybhnpojwjy. B rt hsbii eps hdwj. Be sqj tjresbtj, npdiy vpd srxj r ippx rs sqj nptadsjw ubijh sp hjj zqp tbfqs qroj qry rnnjhh sp cpsq tjtph, rey zqp tbfqs qroj qry sqj paapwsdebsv rey tjreh sp ypnspw sqjt? B rt uivbef crnx sp Irefijv spebfqs, sp hjj bu sqj Hsrsj Yjarwstjes qroj rev byjrh zqrs tbfqs cj fpbef pe. Ejbi hrby qj npdiy uiv tj da be pej pu sqj ERHR nqrhj airejh, zqbnq bh hptjsqbef B qroj cjje xjje sp swv. B zbii nrii vpd bu B fjs revsqbef.

Reveal the correct answer

Correct Answer

Meg, I took a look at the file you sent over and it was just a rotation cipher applied to the text. At first it was hard to say if that was a bug or a feature and normally I would assume bug, but it seemed odd that it was the only file that was affected so I asked around to see if anyone had seen anything similar. It turns out that this was not the first navigation problem to hit the programme. Gene reported a major issue with the guidance programme for Snoopy on the Apollo Ten mission which could again have caused a major problem. For some reason the programme controlling the landing radar wasn’t updated with the flight plan and if Gene hadn’t raised that with Iverson then the boys might have had real trouble getting back. I looked through the company files and found another of our mysteriously formatted reports: the memo informing them about the change, which explains why the programme never got updated. This time the cipher was an affine shift, so slightly harder to crack, but nothing serious. Still, it is much less likely that it was a bug that time, and in any case twice is too much of a coincidence. It did start me wondering why the second cipher was easier to crack than the first, but then I realised that the affine shift was too much of a giveaway. A rotation cipher really could just be an encoding error, but the affine shift is too sophisticated for a mistake, so whoever mangled the reports must have realised they had made a bit of an error with the first one and tried to cover their steps with the second. It is hard to see this as anything other than attempted sabotage, but I am not sure what the motive could be. I doubt it is personal. The Apollo Ten and Eleven crews don’t overlap, so either someone has a grudge against the whole Astronaut corps or they are trying to derail the Apollo programme. It could be the Soviets I suppose. At first, I thought that their willingness to shift the LUNA-FIFTEEN orbit showed that they weren’t part of it, but someone in the State Department pointed out that they might just have had a guilty conscience, or been keen to distance themselves once the plot was discovered. I am still not sure. In the meantime, could you take a look at the computer files to see who might have had access to both memos, and who might have had the opportunity and means to doctor them? I am flying back to Langley tonight, to see if the State Department have any ideas what might be going on. Neil said he could fly me up in one of the NASA chase planes, which is something I have been keen to try. I will call you if I get anything.

Challenge 2

Practice Challenge 2A, Snooping around

Correct Answer

Practice Challenge 2B, A change of course

Correct Answer

Learn More

Resources