Moons of our Solar System: Jupiter´s moons, Prologue

today I will continue to write about moons. Now I will be stucked on the moons of Jupiter for while since it seems that there are about 8 worth a separate posts so this will take some time and today I will try to introduce them.

So for now there are 67 confirmed moons of Jupiter which is most in the whole Solar System. They are named after Jupiter/Zeus´s lovers daughters etc.
After while we run out of those names so we started to repeat them with little changes like: Ganymede>>Ganymed
Callisto>>Kallisto and so on. All moons of Jupiter are tidaly locked.
Those moons are in different groups and the most important are Galilean moons.

Galilean moons are four moons discovered by Galileo Galilei. He discovered them in the year of 1610 even that there are some informations saying that before him chinese found them. What is sure is that independently day after Galileo, Simon Marius found them too and he was the one who gave them the names we use now (before we called them Jupiter I, Jupiter II…).
From left to right you can see on the picture: Io, Europa, Ganymede, Callisto. All of them except Callisto interact through gravitation, they heat each other´s interior through friction.

On the right you can see Galilean moons from Celestia with their orbits. The pie graph shows mass of moons.
Second group really worth mentioning is Amalthea group (beatiful name). Those are inner satellites which orbit really closely to Jupiter.
Members of this group are: Amalthea, Thebe, Adrasthea, Metis.

Amalthea PIA02532.pngBelow you can see picture of Amalthea.

On last picture are the other moons with their irregullar orbits, there arises a question how much should they be considered moons when they are so small.


Pictures taken from: —> here you can find table of all Jupiter´s moons.

Crash Course video Jupiter´s moons


Moons of our Solar System: Deimos

today I will write about even smaller moon than Phobos. This time it is Deimos, again named after kid of Ares (Mars) and Aphrodite (Venus). Deimos was the god of terror/panic/dread. Radius of Deimos is 6.2 kilometers which is almost half of Phobos. This guy was also found by Asaph Hall but 6 days earlier than Phobos.

Deimos is even farther away from his father. When we would watch him from Mars´s surface we would see just a small point and in full Moon he would be bright about as Venus from our point of view, otherwise he could look like ordinary star.

On the GIF you can see Deimos hiding behind much larger Phobos. Its surface should be similar to his brother´s but instead it is much smoother which is made by “sand” which smooths everything out over time.

Martian Moon Deimos in High Resolution

There are only two features named and those are craters Swift and Voltaire named after writers who speculated about moons around Mars even before anybody new they are there.

Its original is not really sure. Usually you will find that Jupiter´s gravitation threw both moons toward Mars and he caught them (this would one reason for so circular orbits of both moons) but most likely they are his kids anyway.

And again his escape velocity is 20.16km/h so if you can run 50 meters in less than 8 seconds you will be able to left him… if it would work like this.


If you have not read about Phobos yet, you should!