Styx and other Pluto Moons

Styx – Pluto Moons | Tiniest Kid of Family

Styx Moon – Basic Information

Origin of Moon Styx

All discoveries in human history started with questions . Some of them like “fire” was applied by just replicating the nature, and some like planets and satellites via just observing their direct or indirect effects.

Moon Styx
Not the best image ever.. Yeah. But the best image of moon Styx we have. Source: NASA

This photo, looking most likely to be taken by a toaster instead of a camera, belongs to the smallest moon of Pluto: Styx, which is the latest discovered one. Although this one is fainter than any other moon in Pluto System, luckily she was bright enough and it was possible to detect her by Hubble Space Telescope; from billions of miles away.

The discovery was not a result of her calculated gravitational effect since she is really small. However it is fairly a result of dedicated astronomers’ digging on Hubble data.

What is Moon Styx?

Styx is a Trans Neptunian, irregular sized object and is the smallest satellite of Pluto. Most of the time she is located in Kuiper belt, with an almost circular orbit around her parental planet. They orbit sun together with other moons.

Similar to those moons, moon Styx is believed to be formed following one or more collisions consequent to Pluto’s grand collision with another big object.

Orbit and Rotation

Except Charon, all Pluto moons’ movements can be summarized as: Chaotic rotation on their axis and almost perfect circular rotation around systems’ gravitational center (barycenter). Basic explanation of that behaviour is:
1) They are too small to stabilize their axes rotation.
2) They are too small to avoid dominance of Pluto-Charon System’s gravitational effect.

Styx is the closest moon to the barycenter after Charon.

Orbits of all Pluto and all moons. Credit: NASA/JHUAPL/SwRI/Mark Showalter Video produced by AGU

One complete rotation on her own axis takes 3 days and 6 hours. However this might vary due to her chaotic movement). In addition, one complete orbiting time is precisely measured as 20.2 days, 42.656 kilometers apart from the barycenter.

Since all Pluto moonsorbital eccentricity is close to zero, all eventually align with one each other at some time. While moon Styx aligning with Nix, the distance between those two satellites goes down to 6.000 kilometers: Similar to distance between London and Washington!

This happens once in 250 days and is seriously a short distance but it seems the Pluto System has been gravitationally stable at least for hundreds of millions of years despite of that proximity!

Styx and other Pluto Moons
Pluto family portrait. Source: NASA, Credits: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team

Size and Structure

Styx is one of the smallest moons we know in our solar system. We are pretty sure Pluto might have more moons which are hundreds of meters in size, but probably it won’t be easy to detect rest of them without a new close-by mission or searching for them.

Is it really worth to search for another one? The answer is no.

Moon Styx is a magnified potato, and its dimensions are roughly: 16 x 9 x 8 kilometers.

OK, now is the time. Walk down to our huge Plutopic kitchen, open the top drawer where you can see the convenient hypothetical huge knife for our mission.

Big knife

Gently slice Styx into half. The inner surface area of the hemisphere will be similar in size with the micro country San Marino.

Surface Features

It’s quite dangerous to walk on Styx moon surface. When we mean “walking“, do not think that you can freely walk the way you do in earth! One unbalanced jump could cause you to be flung from the corner to the empty space!

Similar to that we know about other moons, Styx most likely has water ice on its surface where methane ice might be there for company.

Before the visit of New Horizons, the info we had about size was seriously wrong. Scientists thought it was 1.5 times bigger!

But before putting the blame on scientists, better keep in mind: 8 kilometers is the broadest radius of Styx. And 8 kilometers mean 50% error at the same time, where distance from Earth to moon Styx is close to 5billion kilometers.

Pluto System Moons
Pluto family portrait #2, in consistent sizes. Source: NASA

Living on Styx

In case you too are sick of humanity, like to be alone and want to buy a vacant moon; Styx is a good idea with the size. Even you can plan daily global jogging sessions for yourself.

However Plutopic recommends you to risk Pluto System’s small moons’ orbital stability and arrange a towing vehicle to bring her to a proper Habitable Zone; preferrably to Earth’s orbit. It will not be easy to create a habitat and protect the moon you own from solar winds, other sources of radiation and undesired impacts of meteorites. But if heart wants..

Actually Royksopp tried that with a smallar object on their music video for “Monument” song.

In worst case, you might consider putting a Styx flag to your piece of land and towing your own Styx to Earth directly. In this way, you can get rid of unpleasant limitations of living somewhere else other than the Earth.

This time you’ll have to find a proper place to anchor Styx without jeopardizing territorial waters of any country. In addition, you have to avoid asteroid miners and scientists invading your lands.. As you see, there’s no way to live in peace on any kind of Earth!

Speaking of vacant moons, a great song from progressive death metal gods: DeathVacant Planets

Enough with fictional stories! There’s no slight possiblity that there’s a kind of life we know on moon Styx.

Styx Moon – Story of Discovery

This small object was luckily quite bright to be observed from that far. Thanks to Mark Showalter and the New Horizons Team for their efforts, Styx was detected on mid 2012 during teams’ researches before the spacecraft reached to Pluto area. The identification of moon Styx was confirmed on 9 July 2012 and discovery was officially announced on 11 July 2012.

The machine used for this discovery is the Hubble Space Telescope as for many other objects in the universe.

Styx Moon – Naming

The team of discovery requested some suggestions from public for proper mythological Greek names and asked public to vote for the names. According to voting results, thename Styx was the 3rd, but IAU still agreed on Styx.

One of the main reasons to pick that name is the science-fiction novel Calling Captain Future written by Edmond Hamilton. This novel was written in 1940 when none of the Pluto moons were discovered yet. The author named 3 of moons as Styx, Charon and Kerberos. Names of rest of the Pluto moons Nix and Hydra were first to be mentioned in 21th century.

Inspirational novel about naming Charon

IAU announced naming on 2 July 2013 together with Kerberos.

Styx is a river and a sort of god in Greek mythology, which is basically a boundary in between Earth and the underworld.

Styx in Astrology

Moon Styx, its size, distance to earth, gravitational effect or any other characteristics have nothing to do with your horoscope, your daily life or anything else about your mood. This is common for any satellite, planet or star you can think of.

In addition, Styx is seriously small in size to be neglected in this vast solar system.. But still bigger with respect to a human’s daily worries.

Astrology means fairy tales.

Astronomy relies on facts; on a thing we named in last few centuries: The Science.


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