How many previously unknown moons were discovered around Uranus and Neptune collectively?

Solution

Astronomers have discovered three previously unknown moons around Uranus and Neptune, the most distant planets in our solar system. The find includes one moon spotted orbiting Uranus — the first discovery of its kind in more than 20 years — and two detected in Neptune’s orbit. The three newly discovered moons are the faintest ever found around these two ice giant planets using ground-based telescopes. The revelations will be helpful for missions that may be planned to explore Uranus and Neptune more closely in the future, a priority for astronomers since the ice planets were only observed in detail with Voyager 2 in the 1980s. The three moons were announced on February 23 by the International Astronomical Union’s Minor Planet Center.