What Does Pluto Most Resemble

Introduction

Pluto is a complex and mysterious globe with mountains, valleys, plains, craters, and peradventure glaciers. Discovered in 1930, Pluto was long considered our solar organization's ninth planet. Just after the discovery of similar intriguing worlds deeper in the distant Kuiper Belt, icy Pluto was reclassified as a dwarf planet.

Pluto is but near 1,400 miles wide. At that small size, Pluto is but about half the width of the U.s.. It'southward most iii.six billion miles away from the Sun, and it has a thin atmosphere composed mostly of nitrogen, methane, and carbon monoxide. On average, Pluto's temperature is -387°F (-232°C), making it too cold to sustain life.

Pluto is orbited by 5 known moons, the largest of which is Charon. Charon is nearly half the size of Pluto itself, making it the largest satellite relative to the planet information technology orbits in our solar arrangement. Pluto and Charon are frequently referred to as a "double planet."

Namesake

Pluto is the just earth (so far) named past an eleven-year-quondam girl. In 1930, Venetia Burney of Oxford, England, suggested to her grandfather that the new discovery be named for the Roman god of the underworld. He forwarded the name to the Lowell Observatory and information technology was selected.

Picture of Venetia Burney — Venetia Burney, the girl who named Pluto.

Pluto'due south moons are named for other mythological figures associated with the underworld. Charon is named for the river Styx boatman who ferries souls in the underworld (too as honoring Sharon, the wife of discoverer James Christy); Aught is named for the female parent of Charon, who is as well the goddess of darkness and dark; Hydra is named for the 9-headed serpent that guards the underworld; Kerberos is named after the three-headed dog of Greek mythology (and chosen Fluffy in the Harry Potter novels), and Styx is named for the mythological river that separates the world of the living from the realm of the dead.

Pluto's place in mythology can get a little muddled, so we asked Dr. Elizabeth Vandiver, chair of the Department of Classics in Whitman College in Walla Walla, Washington, to analyze the origins of the name: "Pluto is the name of the Roman god of the Underworld, equivalent to the Greek Hades. However, the Greek name "Plouton" (from which the Romans derived their name "Pluto") was besides occasionally used as an alternative name for Hades. Just Pluto is definitely the Roman spelling."

Potential for Life

The surface of Pluto is extremely cold, so it seems unlikely that life could exist there. At such common cold temperatures, water, which is vital for life equally we know it, is essentially stone-like. Pluto's interior is warmer, however, and some call up there could even be an ocean deep inside.

Size and Distance

With a radius of 715 miles (i,151 kilometers), Pluto is virtually 1/6 the width of Earth. If Earth was the size of a nickel, Pluto would be about as big as a popcorn kernel.

From an average distance of three.vii billion miles (v.9 billion kilometers), Pluto is 39 astronomical units away from the Dominicus. One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this altitude, it takes sunlight 5.5 hours to travel from the Sun to Pluto.

If you were to stand on the surface of Pluto at noon, the Sun would exist 1/900 the effulgence it is here on World, or most 300 times as brilliant equally our total moon. There is a moment each day near sunset hither on Earth when the light is the same brightness equally midday on Pluto. Detect out when you can feel "Pluto fourth dimension" where you live.

Orbit and Rotation

Pluto'south orbit around the Sun is unusual compared to the planets: it'due south both elliptical and tilted. Pluto'south 248-year-long, oval-shaped orbit can take it as far every bit 49.3 astronomical units (AU) from the Lord's day, and as close as thirty AU. (One AU is the mean distance between World and the Lord's day: about 93 one thousand thousand miles or 150 one thousand thousand kilometers.) But on average, Pluto is iii.vii billion miles (five.9 billion kilometers) abroad from the Sun, or 39 AU.

From 1979 to 1999, Pluto was near perihelion, when information technology is closest to the Sun. During this fourth dimension, Pluto was actually closer to the Sunday than Neptune.

One 24-hour interval on Pluto takes about 153 hours. Its centrality of rotation is tilted 57 degrees with respect to the plane of its orbit around the Sun, so information technology spins almost on its side. Pluto also exhibits a retrograde rotation; spinning from east to due west similar Venus and Uranus.

Moons

Pluto has five known moons: Charon, Nix, Hydra, Kerberos, and Styx. This moon system might have formed by a collision betwixt Pluto and some other similar-sized body early in the history of the solar arrangement.

Charon, the biggest of Pluto'south moons, is about half the size of Pluto itself, making it the largest satellite relative to the planet it orbits in our solar system. It orbits Pluto at a distance of just 12,200 miles (nineteen,640 kilometers). For comparison, our Moon is 20 times farther away from Earth. Pluto and Charon are often referred to as a double planet.

Charon's orbit around Pluto takes 153 hours – the same time information technology takes Pluto to complete ane rotation. This means Charon neither rises nor sets, but hovers over the aforementioned spot on Pluto's surface. The aforementioned side of Charon ever faces Pluto, a country called tidal locking.

Pluto's other 4 moons are much smaller, less than 100 miles (160 kilometers) wide. They're also irregularly shaped, non spherical like Charon. Unlike many other moons in the solar system, these moons are not tidally locked to Pluto. They all spin and don't keep the same face towards Pluto.

Rings

At that place are no known rings around Pluto.

Formation

Germination

Dwarf planet Pluto is a fellow member of a group of objects that orbit in a disc-like zone across the orbit of Neptune called the Kuiper Belt. This distant realm is populated with thousands of miniature icy worlds, which formed early on in the history of our solar system about four.five billion years ago. These icy, rocky bodies are called Kuiper Belt objects, transneptunian objects, or plutoids.

Construction

Structure

Pluto is well-nigh two-thirds the bore of Earth'south Moon and probably has a rocky core surrounded by a mantle of water ice. Interesting ices similar marsh gas and nitrogen frost coat the surface. Due to its lower density, Pluto's mass is near one-sixth that of Globe's Moon.

Surface

Pluto'southward surface is characterized by mountains, valleys, plains, and craters. The temperature on Pluto can be as cold as -375 to -400 degrees Fahrenheit (-226 to -240 degrees Celsius).

Pluto'southward tallest mountains are 6,500 to 9,800 anxiety (2 to 3 kilometers) in height. The mountains are big blocks of h2o water ice, sometimes with a coating of frozen gases like methyl hydride. Long troughs and valleys as long every bit 370 miles (600 kilometers) add to the interesting features of this faraway dwarf planet.

Craters as big as 162 miles (260 kilometers) in bore dot some of the landscape on Pluto, with some showing signs of erosion and filling. This suggests tectonic forces are slowly resurfacing Pluto.

The most prominent plains observed on Pluto appear to be made of frozen nitrogen gas and show no craters. These plains do testify structures suggesting convection (blobs of cloth circulating upwardly and down).

A 3D model of Pluto. Credit: NASA Visualization Technology Applications and Development (VTAD) › Download Options

Atmosphere

Pluto has a thin, tenuous temper that expands when information technology comes closer to the Sunday and collapses as it moves farther abroad – similar to a comet. The main constituent is molecular nitrogen, though molecules of methyl hydride and carbon monoxide take as well been detected.

When Pluto is close to the Sun, its surface ices sublimate (changing straight from solid to gas) and rise to temporarily form a thin temper. Pluto's low gravity (nigh vi% of World's) causes the atmosphere to be much more than extended in altitude than our planet'south atmosphere. Pluto becomes much colder during the role of each year when it is traveling far away from the Sun. During this time, the bulk of the planet's atmosphere may freeze and fall as snow to the surface.

Magnetosphere

It isn't known whether Pluto has a magnetic field, but its small size and slow rotation suggest little or none.

Resources

New Horizons Mission Website
NASA Planetary Photojournal: Pluto
Pluto 3D Model
Pluto Poster - Version A
Pluto Poster - Version B
Pluto Affiche - Version C