After the encounter Mariner 10 was in an orbit around the Sun such that for every one of its orbits Mercury made two , and the spacecraft and the planet would be able to meet again .
This was the first observation made of Mercury at close range .
After the encounter Mariner 10 was in an orbit around the Sun such that for every one of Mercury 's orbits Mercury made two , and the spacecraft and the planet would be able to meet again .
This was the first observation made of Mercury at close range .