When did US solar system probe Voyager-two discovered six new moons of the planet Uranus?

1986
1916
1946
1966

The correct answer is A. 1986.

Voyager 2 was a space probe launched by NASA on August 20, 1977. It was the second of two Voyager spacecraft, and the only one to visit Uranus and Neptune. Voyager 2 made its closest approach to Uranus on January 24, 1986, and discovered six new moons of the planet. The moons were named Cordelia, Ophelia, Bianca, Cressida, Desdemona, and Juliet.

Option B, 1916, is incorrect because Voyager 2 was not launched until 1977.

Option C, 1946, is incorrect because Voyager 2 was not launched until 1977.

Option D, 1966, is incorrect because Voyager 2 was not launched until 1977.