▁roll ▁in ▁through ▁doors , ▁w ound ▁in ▁a ▁wheel ▁shape ▁and ▁then ▁un roll ▁to ▁craw l ▁up ▁the ▁st airs , ▁while ▁others ▁craw l ▁down ▁st airs ▁and ▁wind ▁up ▁to ▁roll ▁out . ▁The ▁went elte ef je ▁first ▁appeared ▁earlier ▁the ▁same ▁month ▁in ▁the ▁l ith ograph ▁C url - up . ▁Later ▁that ▁month , ▁House ▁of ▁St airs ▁was ▁extended ▁to ▁a ▁vertical ▁length ▁of ▁ ▁in ▁a ▁print ▁titled ▁House ▁of ▁St airs ▁II ▁by ▁repeating ▁and ▁mirror ing ▁some ▁of ▁the ▁architecture ▁and ▁cre atures . ▁ ▁References ▁▁▁ ▁Category : Work s ▁by ▁M . ▁C . ▁E scher ▁Category : 1 9 5 1 ▁prints <0x0A> </s> ▁Science - En abling ▁Techn ologies ▁for ▁H eli oph ys ics ▁( SE TH ) ▁is ▁a ▁proposed ▁space ▁mission ▁by ▁NASA ' s ▁God d ard ▁Space ▁Fl ight ▁Center ▁to ▁launch ▁a ▁small ▁satellite ▁that ▁would ▁demonstrate ▁new ▁techn ologies ▁to ▁detect ▁solar ▁ener get ic ▁particles , ▁and ▁demonstrate ▁an ▁optical ▁communication ▁system ▁based ▁on ▁las er ▁p uls es . ▁ ▁The ▁Princi pal ▁Investig ator ▁for ▁SET H ▁is ▁An tt i ▁Pul kk inen ▁at ▁NASA ' s ▁God d ard ▁Space ▁Fl ight ▁Center ▁in ▁Green b elt , ▁Maryland . ▁ ▁Over view ▁ ▁Its ▁science ▁payload ▁would ▁be ▁a ▁novel ▁det ector ▁of ▁solar ▁ener get ic ▁neutral ▁atoms ▁( EN A ), ▁as ▁well ▁as ▁an ▁array ▁of ▁waves ▁and ▁other ▁Sol ar