Kerberos Discovery Picture

Kerberos – Pluto Moons | Discreet Son of Solar Anarchy

Kerberos Moon – Basic Information

Where is Moon Kerberos Coming From?

Everything seems to have a beginning and an end in the universe, where the universe itself might be an exception. Although we do not have clear ideas if there is something our minds can grasp beyond the universe, we have serious knowledge about what there is within our universe. And how things basically happened.

Imagine we could scale down everything known including the time itself. From the Big Bang till today. In this way, we can have a basic picture of galaxy groups, galaxies and star systems. Similarly it’s possible to figure out fundamentals of our solar system. After all we have basic idea how solar system formed through previously extincted stars’ residues. Likewise, Moon Kerberos was formed via the birth of a star system by means of Sun’s residues. And similar to others, she is formed as a result of the anarchy caused by this birth.

Kerberos Moon
Best image of Moon Kerberos, via New Horizons spacecraft during its Pluto flyby. Probably you noticed the surface looks rugged in organized patterns, similar to a golf ball. It’s not because a blessed hand touched Kerberos. It’s the low resolution. Source: NASA

What Is Moon Kerberos?

Kerberos is a Trans Neptunian, irregular sized object and is the second smallest satellite of Pluto. She is mostly located in Kuiper belt with an almost circular orbit around her parental planet. As is understood, Kerberos moon is travelling around sun together with Pluto and other moons: Charon, Hydra, Nix and Styx.

Even referring to this low resolution photo, one can easily say that moon Kerberos is formed by zipping two different rocks together. That seems to be true and this appearance clearly reflects the result of a merger after a collision of those.

Orbit and Rotation

Kerberos is the second outermost moon in Pluto orbit. Because of her small size, she could not succeed to round into a proper sphere and stayed as a two lobed body.

Rotation on her own axis is chaotic as it is for the rest of mini Pluto moons. It takes about 5 days and 8 hours to complete this unpredictable rotation. However researchers estimate that it probably varies in short astronomical time intervals.

Luckily there is one consistent motion of moon Kerberos we know: It takes 32.2 days for Kerberos to complete one turn around Pluto System‘s barycenter. And the distance to the barycenter is 57.783 kilometers in average during the orbit.

An illustration of moon Kerberos orbiting barycenter of Pluto System together with others. Credit: NASA/JHUAPL/SwRI/Mark Showalter. Video produced by AGU

Size and Structure

We mentioned above that Kerberos was formed via a brutal collision of two big rocks.

At first glance, it looks like microscobic view of magnified organic cells during the reproducing process. Ironically, we know Kerberos is formed in a kind of opposite and destructive way.

Reproducing cells
Illustrated view of reproducing yeast cells. Source.

Kerberos basically consists of two merged bodies. And the overall dimensions are roughly: 19 x 10 x 9 kilometers.

Now it’s time for Plutopicians to detach the huge hypotethical knife from where it’s plunged. Time to slice!

Instead of our usual method, this time slice Kerberos horizontally from the middle. We are doing this for having a bigger inner surface area to visualize and correlate.

Yeah, shape of Kerberos reminds peanuts as well!

Surface area of one inner part will be similar in size with surface area of lovely city Stockholm.

It’s not easy to walk on a small rock when it’s full of big craters. In addition, lack of sufficient gravity makes it harder to hold on to the land.

All tiny Pluto moons have water ice on surface. So does moon Kerberos. Consequently, you might think the land would be slippery as well because there is water ice on surface. However the surface is more of a rocky form because the temperature is always below -200ºC. And such surface formation will not cause that kind of trouble.

Living on Kerberos

There is always a chance to observe life, at least in microbic forms somewhere else than Earth. This is already being searched on closer targets.

But Kerberos is a little object and is far enough. And there is less possibility even in terms of microbic life forms. That’s why it would not be the best choice to land and take samples for such purpose. We’d better leave her alone!

Pluto moons
Please pick another moon to live in. Source: NASA

Kerberos Moon – Story of Discovery

Noone was looking for it!

Before New Horizons Spacecraft started its journey, team members of this mission (Pluto Companion Search Team) initiated several different researches via Hubble Space Telescope. The idea was to gather more information about Pluto and her neighborhood in order optimize tasks before Pluto arrival. And Mark Showalter, the team leader was definitely not in search for another moon when they came up with the discovery. Who cares about a rock with that small size after all!

They were actually looking deeply around Pluto. Instead of moon(s), they were only searching for Pluto rings!

On July 3 and July 11 researchers verified that the observed object was moon Kerberos. And they announced the discovery on 20 July 2011.

An interesting fact about this discovery is:After the discovery in 2011, the team realised that they have already captured a similar view during previous observations in 2006 and 2010. At that time, reflection of sunlight from Kerberos was not cosidered as a sign of a planetary object. As it is remarkably small sized, team members thought it was just a false diffraction. For understanding how pale Kerberos is, please see below image.

Kerberos and other Pluto moons
Discovery image of Kerberos via Hubble Space Telescope, where P4 is Kerberos itself. Source: NASA, Credits: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team

Kerberos Moon – Naming

While naming Pluto moons, IAU (International Astronomical Union) always tries to stick with proper titles which are related to Pluto in ancient Greek mythology. This did not change for this Pluto moon as well.

IAU announced naming of this tiny moon on 2 July 2013, together with the moon Styx.

Kerberos is the Greek spelling form of word Cerberus. And Cerberus is a dog with several heads in Greek mythology. It is a guardian for the gates between real world and the world of the dead.

The name Styx is also delineated as the river between those worlds in mythology.

Kerberos Moon in Astrology

Kerberos has always been of interest in astrology and will effect you deeply in case you ignore her. Otherwise.. Well obviously that’s a joke 🙂

Moon Kerberos, its size, distance to Earth, gravity or any feature of her has nothing to do with your horoscope, your relationships or anything else about your mood as well as any other planet. This is common for any satellite, planet or star you can think of.

Astrology means fairy tales.

Astronomy relies on facts; on what we call in last few centuries: The Science.


  • We aim to build a proper Pluto encyclopedia and your contributions are highly appreciated!
  • Any deficiencies on this article? Please type to below comment box or contact us from this link. We are ready to check and clarify.

One Response

  1. Ryan Cornell August 2, 2019

Leave a Reply