Die twee ruimtetuie, nog steeds aan mekaar gekoppel, wentel om Mars vir langer as 'n maand en stuur gedurende die tyd beelde na die aarde sodat geskikte landingsareas uitgesoek kan word. Die tweeruimtetuie ontkoppel en die landingstuie dring Mars se atmosfeer binne en doen 'n sagte landing op die gekose landings gebiede. Viking 1 het op 20 Julie 1976 geland en Viking 2 op 3 September. Die wenteltuie het aan hou wentel om Mars, foto's geneem en ander wetenskaplike toetse uitgevoer terwyl die landingstuie meetinstrumente op Mars se oppervlakte ontplooi het.
Die projek het ongeveer VS $1 biljoen in 1970 gekos,<ref name="nssdc-viking1orbiter" /><ref name="space.com">{{Cite news|url=http://www.space.com/18234-viking-1.html|title=Viking 1: First U.S. Lander on Mars|newspaper=Space.com|access-date=2016-12-13}}</ref> die ekwivalent aanvan ongeveer $5 biljoen in 1970. Die missie is as suksesvol beskou en word ook beskou as die program wat die meeste inhoud tot die inligting oor Mars tussen 1990 en 2000 bygedra het.<ref>{{Inflationcite web|US url=http://planetary-GDPscience.org/mars-research/mars-landings/the-viking-program/|1 publisher=The Center for Planetary Science|1970 title=The Viking Program|r access-date=0April 13, 2018}}in</ref><ref>{{cite 1970web| url=https://californiasciencecenter.org/exhibits/air-space/mission-to-the-planets/viking-lander | publisher=California Science Center| title=Viking Lander| date=July 3, 2014| access-date=April 13, 2018}}</ref>
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The project cost roughly US$1 billion in 1970s dollars,<ref name="nssdc-viking1orbiter" /><ref name="space.com">{{Cite news|url=http://www.space.com/18234-viking-1.html|title=Viking 1: First U.S. Lander on Mars|newspaper=Space.com|access-date=2016-12-13}}</ref> equivalent to about {{Inflation|US-GDP|1|1970|r=0}} billion USD in {{Inflation-year|US-GDP}} dollars.{{Inflation-fn|US-GDP}} The mission was considered successful and is credited with helping to form most of the body of knowledge about Mars through the late 1990s and early 2000s.<ref>{{cite web| url=http://planetary-science.org/mars-research/mars-landings/the-viking-program/| publisher=The Center for Planetary Science| title=The Viking Program| access-date=April 13, 2018}}</ref><ref>{{cite web| url=https://californiasciencecenter.org/exhibits/air-space/mission-to-the-planets/viking-lander | publisher=California Science Center| title=Viking Lander| date=July 3, 2014| access-date=April 13, 2018}}</ref>
