Artist's concept of Mariner 5 near Venus

Four months after launch, Mariner 5 flies within about 4,000 kilometers (approximately 2,500 miles) of Venus. Using instruments more sensitive than those aboard Mariner 2 on its Venus encounter, Mariner 5 observes new information about Venus' atmosphere, including its composition of 85-99% carbon dioxide.

Following its Venus encounter, Mariner 5's flight path brings it closer to the Sun than any previous probe.

Download image 120kb