Table:
text: List of interplanetary voyages
1960s
1960s
Spacecraft Destination Launched Closest_approach Time_elapsed
Venera 2 Venus 12 November 1965 27 February 1966 108 days (3 months, 16 days)
Mariner 5 Venus 14 June 1967 19 October 1967 128 days (4 months, 6 days)
Mariner 6 Mars 24 February 1969 31 July 1969 158 days (5 months, 8 days)
Mariner 7 Mars 27 February 1969 5 August 1969 160 days (5 months, 10 days)

Question: What started 158 days (5 months, 8 days) as the elapsed time from the list of interplanetary travel in the 1960s?