Neptune

It flew past the planet in August 1989.

Its retrograde orbit suggests it is a captured Kuiper Belt object, and it has geysers that spray nitrogen.

It completed its first full orbit since discovery in 2011.

Winds on the ice giant reach roughly 2,000 kilometers per hour.

Urbain Le Verrier and John Couch Adams calculated its position from irregularities in Uranus's orbit, and Johann Galle found it in Berlin in September 1846.

Ruled by Neptune, the planet of dreams and illusions, Pisceans frequently experience vivid dreams, prophetic visions, and strong intuition. This blurs the line between reality and the subconscious, often guiding their spiritual path.

Jupiter traditionally ruled Pisces, but Neptune's 1846 discovery led modern astrologers to assign it as Pisces' co-ruler. Neptune's association with dreams, illusions, spirituality, and the subconscious perfectly aligns with the sign's ethereal nature.

Unlike the gas giants Jupiter and Saturn, Uranus and Neptune are primarily composed of "ices" — water, ammonia, and methane — in their interiors, rather than just hydrogen and helium. These icy materials are compressed into a super-dense fluid state beneath their frigid, turbulent atmospheres.

Scientists believe that under the extreme pressures and temperatures deep within these ice giants, methane breaks down, and carbon atoms are compressed into solid diamonds that then "rain" down through the planets' mantles.