▁were ▁discovered ▁and ▁pl otted ▁from ▁air ▁photos ▁by ▁the ▁Third ▁German ▁Ant ar ctic ▁Ex ped ition ▁( 1 9 3 8 – 1 9 3 9 ), ▁led ▁by ▁Capt . ▁Alfred ▁R it scher , ▁who ▁named ▁it ▁for ▁August ▁Pet ermann . ▁ ▁Ge ographical ▁features ▁ ▁References ▁ ▁Category : Mount ain ▁ranges ▁of ▁Queen ▁Ma ud ▁Land ▁Category : Pr in cess ▁A str id ▁Coast ▁ ▁simple : P et ermann ▁R anges <0x0A> </s> ▁A ▁slot ▁anten na ▁consists ▁of ▁a ▁metal ▁surface , ▁usually ▁a ▁flat ▁plate , ▁with ▁one ▁or ▁more ▁holes ▁or ▁sl ots ▁cut ▁out . ▁Is ▁a ▁sl otted ▁wave guide ; ▁a ▁wave guide ▁that ▁is ▁used ▁as ▁an ▁anten na ▁in ▁mic row ave ▁rad ar ▁applications . ▁When ▁the ▁plate ▁is ▁driven ▁as ▁an ▁anten na ▁by ▁a ▁driving ▁frequency , ▁the ▁slot ▁radi ates ▁elect romagnet ic ▁waves ▁in ▁a ▁way ▁similar ▁to ▁a ▁di pole ▁anten na . ▁The ▁shape ▁and ▁size ▁of ▁the ▁slot , ▁as ▁well ▁as ▁the ▁driving ▁frequency , ▁determine ▁the ▁radiation ▁pattern . ▁O ften ▁the ▁radio ▁waves ▁are ▁provided ▁by ▁a ▁wave guide , ▁and ▁the ▁anten na ▁consists ▁of ▁sl ots ▁in ▁the ▁wave guide . ▁ ▁S lot ▁anten nas ▁are ▁usually ▁used ▁at ▁U H F ▁and ▁mic row ave ▁frequencies , ▁where ▁the ▁waves ▁are ▁usually ▁conducted ▁by ▁wave guide , ▁so ▁a ▁slot ▁in ▁the ▁wave guide ▁makes ▁a ▁simple ▁anten na . ▁