Neptune how many moons

Neptune is now known to have at least 14 moons, but only one of those moons, Triton, is large enough to be spherical. Compare that to four round moons at Jupiter, seven at Saturn, and five at Uranus. Learn more about Mercury, the extreme little planet. In terms of size, Triton is the seventh-largest moon in the solar system. Learn more about Venus, the veiled greenhouse planet. Triton is orbiting Neptune in the opposite direction that Neptune is spinning.

So, where did Triton come from? Most likely, it came from the Kuiper belt. The most famous Kuiper belt resident is Pluto. Some Kuiper belt objects, including Pluto, are known to have elliptical orbits that cross the orbit of Neptune.

Learn more about exploring the Earth-Moon system. Now, capturing Triton would have taken its toll on both Triton and the Neptune system. Imagine if Neptune originally had a system of regular moons that had formed from an accretion disk.

Then Triton comes barreling in, and the gravitational interactions between Triton and these moons would likely have disrupted their orbits: perhaps giving them large eccentricities or inclinations, causing them to crash into Neptune or escape the Neptune system altogether. Nereid, a small moon of Neptune may be evidence of this.

This is a transcript from the video series A Field Guide to the Planets. Watch it now, Wondrium. And how did going from a free-flying Kuiper belt object to a captured moon affect Triton? Triton now keeps one face towards Neptune at all times, just like our Moon does with Earth, and travels in a very circular orbit. The tidal forces acting on Triton this close to Neptune have two important effects on the moon. Triton is slowly spiraling inward towards Neptune. Tidal forces are not only pulling Triton inward.

Use Chemistry. JPL's lucky peanuts are an unofficial tradition at big mission events. Full Moon Guide: October - November The rover will be delivered to the Moon's surface in late VIPER is the first resource-mapping mission on the surface of another celestial body.

Full Moon Guide: September - October For the first time, astronomers have uncovered evidence of water vapor in the atmosphere of Jupiter's moon Ganymede. The cliff walls seen in the inset are higher than those of the Grand Canyon on Earth. Uranus' smallest moons are its innermost satellites. Portia heads a group of 8 inner satellites. The Portian orbit is slowly decaying due to tidal deceleration and may one day either break apart to form a planetary ring or could potentially collide with Uranus.

Orbits of the other satellites in the Portia Group have a similar fate. Neptune has 13 known moons, though most are small and orbit closer to Neptune than its rings. Triton is Neptune's only large moon with a diameter of 2, km, and Proteus and Nereid are Neptune's second and third largest moons, respectively.

Voyager 2 discovered many of Neptune's moons in , and took pictures revealing many previously unknown properties of Triton. Triton's icy, spherical surface reflects so much of the sunlight it receives that it is the coldest world in the solar system. Triton is the only moon in the solar system with a retrograde orbit. This, along with Triton's high inclination relative to Neptune's equator, suggests that Triton may have been captured from interplanetary space.

Photos of Triton show a strange surface shaped by more than just impact cratering, although its many undisturbed craters suggest that major geologic activity has subsided. Regions on Titan's surface show evidence of past volcanic and tectonic activity. The internal heat source for Triton's geologic activity is not known, but it may involve tidal heating.

The sublimation of surface ices creates a thin, hazy atmosphere on Triton made mostly of Nitrogen. The atmosphere creates wind streaks on the surface, and unknown processes pump unusual plumes of gas and particles into the atmosphere.

Titan: What lies beneath the smog? Saturn's Medium-Size Moons.