Celestia Forums

Io, Europa, Ganimede & Callisto are the 4 Galilean moons. That means Galileo Galilei discovered them right? well, I'm sorry to tell you that its not right. Someone else discovered them, someone unknown. And then Galileo stold the discover and give them his name.
Interesting isn't it?

It was an english astronomer who discovered them independently, at almost the same time as galileo. I have seen his name before but can't remember it now... I know it wasn't galileo that came up with the names, but i'm not sure if it was the english guy who did...

German guy - Simon Mayer, who Latinized his name to Simon Marius.
He certainly gave names to the individual Galileans, which Galileo hadn't named, and claimed to have observed them independently of Galileo, thus getting into a wrangle with him over priority.
But I've never seen any suggestion that Galileo "stole" the discovery from Marius - quite the reverse, in fact. Where did you get your information, El Pelado?

Grant

i've been assitsing to astronomy classes. in those classes we heard about a principal topic, we asked. and then we watch trough a telescope.
the man who give the classes said many times that galileo stole the discover from other astronomer. but i don't know the name of that one.
sorry.

Yeah, it was Simon Marius. What I'd gathered was that he saw them earlier but never published his observations, whereas Galileo did. Which just goes to show that one shouldn't wait around to publish one's results in science, because someone else may beat you to it.

But certainly the assertion that Galileo stole any results from him is false - Galileo just published first, and that's what matters. That said, it seems that Marius plagiarised a few other ideas from Galileo. You can read the sordid story all from Galileo's pen at:

http://es.rice.edu/ES/humsoc/Galileo/People/marius.html