Moons of Uranus these five, Titania, is 1,578 km in diameter and the eighth-largest moon in the Solar System, and about one-twentieth the mass the Earth's Moon. The orbits of the regular moons are nearly coplanar with Uranus's equator, which is tilted 97.77° to its orbit. Uranus's irregular moons have elliptical and strongly inclined (mostly retrograde) orbits at large distances from the planet. William Herschel discovered the first two moons, Titania and Oberon, in 1787, and the other three ellipsoidal moons were discovered in 1851 by William Lassell (Ariel and Umbriel) and in 1948 by Gerard Kuiper (Miranda). These five have planetary mass,
A Beautiful Planet twisted, inverted; you can completely lose your spatial awareness about where you are and what your attitude is, and you can easily get tangled up in that safety tether if you're not cautious. Every single movement you make, you're making an effort to think [things] through." After spending almost the entire film scrutinizing the Earth and the ISS (with its astronauts) in low Earth orbit, one of the final scenes of "A Beautiful Planet" briefly examines an important extrasolar planet (a planet outside of our solar system) which was discovered in 2014. The planet, Kepler-186f, was the first approximately-Earth-sized planet